CN113061168A

CN113061168A - Truncated fever with thrombocytopenia syndrome virus Gn protein and application thereof

Info

Publication number: CN113061168A
Application number: CN202110331589.3A
Authority: CN
Inventors: 聂李亚; 马素永; 许松山; 汤晓闯; 梁明征; 马杉姗; 韩成权
Original assignee: Beijing Northland Biotech Co Ltd
Current assignee: Beijing Northland Biotech Co Ltd
Priority date: 2021-03-29
Filing date: 2021-03-29
Publication date: 2021-07-02
Anticipated expiration: 2041-03-29
Also published as: CN113061168B

Abstract

The present application relates to truncated febrile associated thrombocytopenia syndrome virus Gn proteins, fusion proteins comprising said truncated Gn proteins, nucleic acid molecules comprising nucleotide sequences encoding said truncated Gn proteins or fusion proteins, and vectors and host cells comprising said nucleic acid molecules. Furthermore, the present application relates to a pharmaceutical composition comprising said truncated Gn protein, fusion protein, nucleic acid molecule or vector.

Description

Truncated fever with thrombocytopenia syndrome virus Gn protein and application thereof

Technical Field

The present application relates to the field of genetic engineering and molecular biology, in particular to truncated febrile thrombocytopenia syndrome virus Gn proteins, fusion proteins comprising said truncated Gn proteins, nucleic acid molecules comprising nucleotide sequences encoding said truncated Gn proteins or fusion proteins, and vectors and host cells comprising said nucleic acid molecules. Furthermore, the present application relates to a pharmaceutical composition comprising said truncated Gn protein, fusion protein, nucleic acid molecule or vector.

Background

Fever with thrombocytopenia syndrome (SFTS) is an acute infectious disease caused by infection with fever with thrombocytopathogenic syndrome bunyavirus (SFTSV). SFTSV belongs to the genus phlebovirus of the family Bunyaviridae, is mainly transmitted by ticks and can be transmitted by humans, and is first discovered in China in 2009, and recently, the SFTSV is transmitted in most of China in epidemic mode, so that thousands of people are ill and even die.

WHO ranked SFTS as the infectious disease of prior concern in 2017. At present, no specific medicine or effective vaccine is available for preventing the disease, symptomatic support treatment and broad-spectrum antiviral treatment by using ribavirin (ribavirin) and the like are mainly adopted for patients, and researches show that the medicine has no great effect on severe cases (death cases) and the platelet count and the viral load of the medicine are almost unchanged before and after the treatment.

There are currently no approved therapeutics or vaccines for this disease, nor are there varieties that enter clinical trials. Among them, the representative DNA vaccine reported in the previous research (Development of a SFTSV DNA vaccine complex protection against viral infection in vaccines, nature Communications,2019) has achieved good effects, but it uses a mixture of multiple plasmids and is used in a large amount. For example, mice are immunized with 5 plasmids, each plasmid being dosed at 40ug, for a total of 200ug, e.g., a predicted human dose of about 40 mg. The dosage is too large, so that on one hand, the production cost is high, the medication cost of a patient is high, and the burden is heavy; on the other hand, high-dose administration causes more introduced impurities and possibly causes increase of toxic and side effects, thereby increasing clinical risks and being difficult to realize the drug effect.

Therefore, in order to improve clinical therapeutic effects and reduce the amount of use, it is necessary to develop an SFTSV DNA vaccine that can further improve the amount of antigen expression and significantly reduce the clinical dose.

Disclosure of Invention

In the present invention, unless otherwise specified, scientific and technical terms used herein have the meanings that are commonly understood by those skilled in the art. Meanwhile, in order to better understand the present invention, the definitions and explanations of related terms are provided below.

As used herein, the term "SFTSV" is an abbreviation for "fever with thrombocytopenia syndrome bunyavirus (severe fe with thrombocytoplasts syndrome bunyavirus)" which belongs to the genus phlebovirus of the family bunyaviridae and is a minus-strand RNA virus. The genomic sequence of SFTSV is known to those skilled in the art, see, e.g., GenBank: HM 745931.1. SFTSV contains 2 envelope glycoproteins, Gn and Gc proteins, respectively, which play a more important role in the viral infection of cells. Currently, SFTSV has been identified worldwide as 8 genotypes, C1, C2, C3, C4, C5, J1, J2, J3 (styrenic and Geographic Relationships of section river With Thromboporia Syndrome Virus in China, South Korea, and Japan. J infection Dis,2015,212: 889-98).

As used herein, the terms "Gn envelope glycoprotein" and "Gn protein" refer to one of the envelope glycoproteins of SFTSV, which have the same meaning and are used interchangeably. In SFTS related research and vaccine therapy, Gn proteins may serve as antigens, also referred to herein simply as "Gn antigens".

As used herein, the term "truncated Gn protein" refers to a protein produced by deletion of one or more amino acids at the N-terminus and/or C-terminus of a wild-type Gn protein, wherein a specific amino acid sequence of the wild-type Gn protein is available from public databases (e.g., GenBank databases), for example, an amino acid sequence as shown in GenBank accession No. HM745931.1 (HB29 strain), BAN58192.1(SPL035A strain), BAN58191.1 (SPL032A strain), or BAN58187.1(SPL004A strain).

In the present invention, an exemplary amino acid sequence of the SFTSV Gn protein is as shown in SEQ ID NO:1 is shown. Thus, in the present invention, when referring to the sequence of the Gn protein, it is described using the sequence shown in SEQ ID NO. 1. For example, the expression "24 amino acids at the C-terminus of the Gn protein" means the 24 amino acids closest to the C-terminus in SEQ ID NO: 1. However, it is understood by those skilled in the art that mutations or variations (including, but not limited to, substitutions, deletions and/or additions) can be naturally occurring or artificially introduced in SEQ ID NO. 1 without affecting the biological properties of the Gn protein. For example, Gn proteins of different strains of SFTSV may naturally differ in amino acid sequence, but have substantially the same biological properties. Thus, in the present invention, the term "Gn protein" is intended to include all such polypeptides and variants, including the polypeptide set forth in SEQ ID NO:1 and natural or artificial variants thereof, which retain the biological properties of the Gn protein. Also, when describing the sequence fragment and amino acid position of the Gn protein, it includes not only the sequence fragment and amino acid position of the polypeptide shown in SEQ ID NO. 1, but also the corresponding sequence fragment and amino acid position in a natural or artificial variant of the polypeptide. For example, the expression "24 amino acids at the C-terminus of the Gn protein" is intended to include the 24 amino acids at the C-terminus of SEQ ID NO:1, as well as the amino acid residues in variants (natural or artificial) of the polypeptide shown in SEQ ID NO:1 which are at the corresponding amino acid positions to the 24 amino acids at the C-terminus of SEQ ID NO: 1.

As used herein, the expression "corresponding sequence fragment" or "corresponding fragment" refers to a fragment at an equivalent position in the sequences being compared when the sequences are optimally aligned, i.e., when the sequences are aligned for the highest percent identity. According to the invention, the expression "corresponding amino acid position" refers to the amino acid position/residue at the equivalent position in the sequences being compared when the sequences are optimally aligned, i.e. when the sequences are aligned for the highest percentage identity.

As used herein, the term "identity" is used to refer to the match in sequence between two polypeptides or between two nucleic acids. When a position in both of the sequences being compared is occupied by the same base or amino acid monomer subunit (e.g., a position in each of two DNA molecules is occupied by adenine, or a position in each of two polypeptides is occupied by lysine), then the molecules are identical at that position. The "percent identity" between two sequences is a function of the number of matching positions shared by the two sequences divided by the number of positions compared x 100. For example, if 6 of 10 positions of two sequences match, then the two sequences have 60% identity. For example, the DNA sequences CTGACT and CAGGTT share 50% identity (3 of the total 6 positions match). Typically, the comparison is made when the two sequences are aligned to yield maximum identity. Such alignments can be performed by using, for example, Needleman et al (1970) j.mol.biol.48: 443-453. The algorithm of E.Meyers and W.Miller (Compout.appl biosci., 4:11-17(1988)) which has been incorporated into the ALIGN program (version 2.0) can also be used to determine percent identity between two amino acid sequences using a PAM120 weight residue table (weight residue table), a gap length penalty of 12, and a gap penalty of 4. Furthermore, percent identity between two amino acid sequences can be determined using the Needleman and Wunsch (J MoI biol.48: 444-.

As used herein, the term "SFTS" is short for "fever with thrombocytopenia syndrome" which refers to a series of signs or symptoms resulting from SFTSV infection, the clinical manifestations of which are primarily characterized by fever with thrombocytopenia.

As used herein, the term "vector" refers to a nucleic acid delivery vehicle into which a polynucleotide can be inserted. When a vector is capable of expressing a protein encoded by an inserted polynucleotide, the vector is referred to as an expression vector. The vector may be introduced into a host cell by transformation, transduction, or transfection, and the genetic material elements carried thereby are expressed in the host cell. Vectors are well known to those skilled in the art and include, but are not limited to: a plasmid; phagemid; a cosmid; artificial chromosomes such as Yeast Artificial Chromosomes (YACs), Bacterial Artificial Chromosomes (BACs), or artificial chromosomes (PACs) derived from P1; bacteriophage such as lambda phage or M13 phage, animal virus, etc. Animal viruses that may be used as vectors include, but are not limited to, retroviruses (including lentiviruses), adenoviruses, adeno-associated viruses, herpes viruses (e.g., herpes simplex virus), poxviruses, baculoviruses, papilloma viruses, papilloma polyoma vacuolatum viruses (e.g., SV 40). A vector may contain a variety of elements that control expression, including, but not limited to, promoter sequences, transcription initiation sequences, enhancer sequences, selection elements, and reporter genes. In addition, the vector may contain a replication initiation site.

As used herein, the term "host cell" refers to a cell that can be used for introducing a vector, and includes, but is not limited to, prokaryotic cells such as Escherichia coli or Bacillus subtilis, fungal cells such as yeast cells or Aspergillus, insect cells such as S2 Drosophila cells or Sf9, or animal cells such as fibroblast, CHO cells, COS cells, NSO cells, HeLa cells, BHK cells, HEK293 cells, or human cells.

One skilled in the art will appreciate that the design of an expression vector may depend on factors such as the choice of host cell to be transformed, the level of expression desired, and the like. A vector may be introduced into a host cell to produce transcripts, proteins, or peptides therefrom, including from proteins, isolated nucleic acid molecules, and the like, as described herein.

According to the present invention, the term "pharmaceutically acceptable carrier and/or excipient" refers to carriers and/or excipients that are pharmacologically and/or physiologically compatible with the subject and the active ingredient, which are well known in the art (see, e.g., Remington's Pharmaceutical sciences. edited by genomic AR,19th ed. Pennsylvania: Mack Publishing Company, 1995) and include, but are not limited to: pH regulator, surfactant, adjuvant, and ionic strength enhancer. For example, pH adjusting agents include, but are not limited to, phosphate buffers; surfactants include, but are not limited to, cationic, anionic or nonionic surfactants, such as Tween-80; adjuvants include, but are not limited to, aluminum adjuvants (e.g., aluminum hydroxide), freund's adjuvant (e.g., complete freund's adjuvant); ionic strength enhancers include, but are not limited to, sodium chloride.

According to the present invention, the term "adjuvant" refers to a non-specific immunopotentiator which, when delivered together with or in advance of an antigen into the body, enhances the body's immune response to the antigen or alters the type of immune response. Adjuvants are of various types, including, but not limited to, aluminum adjuvants (e.g., aluminum hydroxide), Freund's adjuvants (e.g., complete Freund's adjuvant and incomplete Freund's adjuvant), Corynebacterium parvum, lipopolysaccharide, cytokines, and the like. Freund's adjuvant is currently the most commonly used adjuvant in animal testing. Aluminum hydroxide adjuvants are used more often in clinical trials. In the present invention, it is particularly preferred that the adjuvant is an aluminum adjuvant.

According to the present invention, the term "effective amount" means an amount effective to achieve the intended purpose. For example, an amount effective to prevent or treat a disease (e.g., an SFTSV infection) is an amount effective to prevent, prevent or delay the onset of a disease (e.g., an SFTSV infection), or to ameliorate, reduce or treat the severity of an existing disease (e.g., a disease caused by an SFTSV infection). It is within the ability of those skilled in the art to determine such an effective amount. For example, an amount effective for therapeutic use will depend on the severity of the disease to be treated, the general state of the patient's own immune system, the general condition of the patient, e.g., age, weight and sex, the mode of administration of the drug, and other treatments administered concurrently, and the like.

In the present invention, the terms "polypeptide" and "protein" have the same meaning and are used interchangeably. Also, in the present invention, amino acids are generally represented by single-letter and three-letter abbreviations as is well known in the art. For example, alanine can be represented by A or Ala.

As used herein, "subject" refers to an animal, such as a vertebrate. Preferably, the subject is a mammal, e.g., a human, bovine, equine, feline, canine, rodent, or primate. Particularly preferably, the subject is a human. Herein, the term may be used interchangeably with "patient".

In a first aspect, the present application provides a truncated fever with thrombocytopenia syndrome bunyavirus (SFTSV) Gn protein that is C-terminally truncated by 24 amino acids compared to the native Gn protein.

In certain embodiments, the SFTSV is C1, C2, C3, C4, C5, J1, J2, J3 genotype. In certain embodiments, the SFTSV is a clinical isolate of SFTSV, such as an isolate selected from the group consisting of: SFTSV HB29/China/2010, SFTSV CB1/South Korea/2014, SFTSV KAJNH2/South Korea/2013, SFTSV ZJZHSH-FDE/China/2012, SFTSV KADGH/South Korea/2013, SFTSV SPL035A/Japan, SFTSV SPL032A/Japan, SFTSV SPL004A/Japan, and the like.

In certain embodiments, the amino acid sequence of the native Gn protein is set forth in SEQ ID NO 1.

In certain embodiments, the amino acid sequence of the truncated Gn protein is set forth in SEQ ID No. 3.

In a second aspect, the present application provides a fusion protein comprising a truncated Gn protein as described above and a further polypeptide. In certain embodiments of the present application, the fusion protein is not a naturally occurring protein or fragment thereof. In certain embodiments, the additional polypeptide is heterologous with respect to the truncated Gn protein.

In certain embodiments, the additional polypeptide is linked to the N-terminus or C-terminus of the truncated Gn protein, optionally through a linker (e.g., a peptide linker). Such joints (for example)Such as a peptide linker) are well known in the art, examples of which include, but are not limited to, peptide linkers comprising one or more (e.g., 1, 2, 3, 4, or 5) amino acids (e.g., Gly or Ser). In certain embodiments, the peptide linker is flexible. In certain embodiments, a flexible peptide linker may be advantageous, which is capable of linking two protein/polypeptide components and maintaining their respective activities and functions. Such peptide linkers include, but are not limited to, (GGGGS)₃。

In certain embodiments, the additional polypeptide is selected from a tag, a signal peptide or a leader, a detectable label (e.g., luciferase (fluc), Green Fluorescent Protein (GFP)), or any combination thereof. In certain embodiments, the truncated Gn proteins of the present application may be linked to a tag sequence to facilitate expression, detection, and/or purification of the truncated Gn proteins of the present application. In certain embodiments, the truncated Gn proteins of the present application may be linked to a signal peptide or leader sequence to direct secretion of the truncated Gn proteins of the present application. In certain embodiments, the truncated Gn proteins of the present application may be linked to a detectable marker sequence to facilitate detection or tracking of the truncated Gn proteins of the present application.

In certain embodiments, the signal peptide is selected from the group consisting of a native signal peptide of Gn protein, a native signal peptide of HGF (hepatocyte growth factor), and a native signal peptide of IgE (immunoglobulin E). In certain embodiments, the signal peptide has an amino acid sequence selected from the group consisting of: 10, 13, and 14.

Those skilled in the art will appreciate that signal peptides intended to be encompassed herein include, but are not limited to, those listed above, and those skilled in the art know how to select an appropriate signal peptide for a desired purpose (e.g., secretion or direction of a protein).

In certain embodiments, the fusion protein has an amino acid sequence selected from the group consisting of: 15 and 16.

In a third aspect, the present application provides a nucleic acid molecule comprising a nucleotide sequence encoding a truncated Gn protein as described above or a fusion protein as described above.

In certain embodiments, the nucleotide sequence encoding the truncated Gn protein or fusion protein is codon optimized or non-optimized according to codon preferences of a host cell (e.g., a human cell).

In certain embodiments, the nucleic acid molecule has a nucleotide sequence selected from the group consisting of: 5, 7, and 9.

In certain embodiments, the nucleic acid molecule is DNA.

In a fourth aspect, the present application provides a vector comprising a nucleic acid molecule as described above.

In certain embodiments, the vector is selected from the group consisting of a plasmid; phagemid; a cosmid; artificial chromosomes such as Yeast Artificial Chromosomes (YACs), Bacterial Artificial Chromosomes (BACs), or artificial chromosomes (PACs) derived from P1; bacteriophages such as lambda bacteriophage or M13 bacteriophage; and, viral vectors, such as retroviral vectors (e.g., lentiviral vectors), adenoviral vectors, adeno-associated viral vectors, herpes viral vectors (e.g., herpes simplex viral vectors), poxvirus vectors, baculovirus vectors, papilloma viral vectors, papilloma polyomavirus vectors.

In certain embodiments, the vector is used to express (e.g., express in vivo in a subject (e.g., a mammal, such as a human)) the truncated Gn protein or the fusion protein.

In certain embodiments, the vector is a vector for gene therapy, such as a plasmid, an adenoviral vector, an adeno-associated viral vector, and a lentiviral vector.

In a fifth aspect, the present application provides a host cell comprising a nucleic acid molecule according to the preceding description or a vector according to the preceding description.

In certain embodiments, the host cell is selected from prokaryotic cells, such as e.coli cells, and eukaryotic cells, such as yeast cells, insect cells, plant cells, and animal cells.

In certain embodiments, the animal cell is a mammalian cell, e.g., a mouse cell, a human cell, and the like.

In certain embodiments, the mammalian cell is a human cell, e.g., a hematopoietic cell, an epithelial cell, a liver cell, a tumor cell, a neural cell.

In certain embodiments, the host cell is an e.coli cell, such as e.coli DH 5a cell; alternatively, the host cell is a human cell (e.g., 293T cell).

In a sixth aspect, the present application provides a method of expressing or producing a truncated Gn protein as hereinbefore described or a fusion protein as hereinbefore described, said method comprising the use of a nucleic acid molecule as hereinbefore described or a vector as hereinbefore described or a host cell as hereinbefore described.

In certain embodiments, the method comprises expressing a nucleic acid molecule according to the foregoing or a vector according to the foregoing in a host cell under conditions that allow for expression of the protein; and optionally, recovering the truncated Gn protein or the fusion protein expressed in the host cell.

In a seventh aspect, the application provides the use of a nucleic acid molecule according to the above or a vector according to the above or a host cell according to the above for expressing or producing said truncated Gn protein or said fusion protein. In certain preferred embodiments, the nucleic acid molecule or vector is used to express or produce the truncated Gn protein or the fusion protein in vitro. In certain preferred embodiments, the nucleic acid molecule or vector is used to express or produce the truncated Gn protein or the fusion protein in a cell. In certain preferred embodiments, the nucleic acid molecule or vector is used to express or produce the truncated Gn protein or the fusion protein in vitro, in a cell. In certain preferred embodiments, the nucleic acid molecule or vector is used to express or produce the truncated Gn protein or the fusion protein in vivo. In certain preferred embodiments, the nucleic acid molecule or vector is used to express or produce the truncated Gn protein or the fusion protein in vivo in a subject (e.g., a mammal, such as a human).

In an eighth aspect, the present application provides a pharmaceutical composition comprising a truncated Gn protein according to the preceding description or a fusion protein according to the preceding description or a nucleic acid molecule according to the preceding description or a vector according to the preceding description, and optionally a pharmaceutically acceptable carrier and/or excipient.

In certain embodiments, the pharmaceutical composition is administered by injection.

In certain embodiments, the pharmaceutical composition is an injection or a lyophilized powder.

In certain embodiments, the truncated Gn protein or the fusion protein or nucleic acid molecule or vector is present in an effective amount (e.g., a prophylactically or therapeutically effective amount).

In certain embodiments, the pharmaceutical composition is in unit dosage form.

In certain embodiments, the pharmaceutical composition is a vaccine.

In certain embodiments, the pharmaceutical composition further comprises an adjuvant.

In certain embodiments, the pharmaceutical composition is a protein vaccine comprising a truncated Gn protein as described above or a fusion protein as described above.

In certain embodiments, the pharmaceutical composition is a nucleic acid vaccine comprising a nucleic acid molecule as described above or a vector as described above.

In certain embodiments, the nucleic acid vaccine is a DNA vaccine.

In a ninth aspect, the present application provides a method of preparing a pharmaceutical composition as hereinbefore described, said method comprising admixing a truncated Gn protein as hereinbefore described or a fusion protein as hereinbefore described or a nucleic acid molecule as hereinbefore described or a vector as hereinbefore described with a pharmaceutically acceptable carrier and/or excipient (e.g. an adjuvant).

In a tenth aspect, the present application provides the use of a truncated Gn protein according to the preceding description or a fusion protein according to the preceding description or a nucleic acid molecule according to the preceding description or a vector according to the preceding description for the preparation of a pharmaceutical composition for the prevention or treatment of SFTSV infection or a disease caused by SFTSV infection (e.g. SFTS) in a subject.

In certain embodiments, the subject is a mammal, e.g., a human.

In certain embodiments, the pharmaceutical composition comprises an effective amount (e.g., an effective amount to prevent or treat SFTSV infection or a disease caused by SFTSV infection) of the truncated Gn protein or the fusion protein or nucleic acid molecule or vector.

In certain embodiments, the pharmaceutical composition is in unit dosage form.

In certain embodiments, the pharmaceutical composition is a vaccine.

In certain embodiments, the nucleic acid vaccine is a DNA vaccine.

In an eleventh aspect, the present application provides a viroid-like particle comprising a truncated Gn protein as described above or comprising a fusion protein as described above; alternatively, the viroid consists of a Gn protein as described above or a fusion protein as described above.

In a twelfth aspect, the present application provides a method of preventing or treating SFTSV infection or a disease caused by SFTSV infection (e.g. SFTS) in a subject, comprising administering to a subject in need thereof an effective amount of a truncated Gn protein according to the preceding or a fusion protein according to the preceding or a nucleic acid molecule according to the preceding or a vector according to the preceding or a pharmaceutical composition according to the preceding.

In certain embodiments, the subject is a mammal, e.g., a human.

In certain embodiments, the truncated Gn protein or the fusion protein or nucleic acid molecule or vector or pharmaceutical composition is administered to a subject by injection.

Advantageous effects of the invention

The truncated Gn protein of the present application has significantly increased intracellular expression levels (by more than 5-fold) compared to the native Gn protein. Further, a significantly increased titer of total and neutralizing antibodies to Gn protein (about 5-fold increase) was induced in vivo upon administration of the vector comprising the nucleotide sequence encoding the truncated Gn protein to the subject. Thus, the truncated Gn proteins of the present application, and the nucleic acid molecules encoding them, are particularly advantageous for use as highly effective antiviral vaccines.

Embodiments of the present invention will be described in detail below with reference to examples, but those skilled in the art will appreciate that the following examples are only illustrative of the present invention and do not limit the scope of the present invention. Various objects and advantageous aspects of the present invention will become apparent to those skilled in the art from the following detailed description of the preferred embodiments.

Sequence information

Information on the partial sequences to which the present invention relates is provided in table 1 below.

Table 1: sequence information

Detailed Description

The invention will now be described with reference to the following examples, which are intended to illustrate the invention, but not to limit it.

Unless otherwise indicated, the experiments and procedures described in the examples were performed essentially according to conventional methods well known in the art and described in various references. For example, conventional techniques in immunology, biochemistry, chemistry, molecular biology, microbiology, cell biology, genomics, and recombinant DNA used in the present invention can be found in Sambrook (Sambrook), friesch (Fritsch), and manitis (manitis), molecular cloning: a LABORATORY Manual (Molecular CLONING: A Laboratory Manual), 2 nd edition (1989); a Current Manual of MOLECULAR BIOLOGY experiments (Current PROTOCOLS IN MOLECULAR BIOLOGY BIOLOGY) (edited by F.M. Otsubel et al, (1987)); METHODS IN ENZYMOLOGY (METHODS IN Enzymology) series (academic Press): PCR 2: practical methods (PCR 2: A PRACTICAL APPROACH) (M.J. Mefferson, B.D. Hemsh (B.D. Hames) and G.R. Taylor (edited by G.R. Taylor) (1995)), and animal cell CULTURE (ANIMAL CELL CURTURE) (edited by R.I. Fresherni (R.I. Freshney) (1987)).

In addition, those whose specific conditions are not specified in the examples are conducted under the conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products commercially available. The examples are given by way of illustration and are not intended to limit the scope of the invention as claimed. All publications and other references mentioned herein are incorporated by reference in their entirety.

Example 1 construction of recombinant plasmid

The sequence of the Gn protein used in this example is shown in GenBank accession HM745931.1, wherein the amino acids at positions 1-19 are the sequence of the signal peptide of the native Gn protein (SEQ ID NO:10), and the remaining amino acid sequences are the amino acid sequences of the native Gn protein (as shown in SEQ ID NO:1, and the coding nucleotide sequence thereof is shown in SEQ ID NO: 2). The C-terminal 24 amino acids of the native Gn protein were removed to obtain a truncated Gn protein (the amino acid sequence of which is shown in SEQ ID NO: 3).

The nucleotide sequences encoding the native Gn protein and the truncated Gn protein were optimized according to the codon usage of human cells to obtain the nucleotide sequences shown in SEQ ID NOS 4 and 5.

Then, nucleotide sequences encoding HGF signal peptide or IgE signal peptide were ligated to the 5' -ends of the nucleotide sequences shown in SEQ ID NO. 4 and 5, respectively (the ligated signal peptide coding sequences are shown in SEQ ID NO. 11 and 12, respectively), to obtain the nucleotide sequences shown in SEQ ID NO. 6-9.

The sequences SEQ ID NOS: 6-9 as described above were constructed into pSN vectors (see patent CN108611367B for details and sequence) to obtain recombinant plasmids pSN-FXG-H-0, pSN-FXG-H-1, pSN-FXG-I-0 and pSN-FXG-I-1, and the details of the sequence information are shown in Table 2.

TABLE 2 sequence information of recombinant plasmids

Name of recombinant plasmid	Carrying nucleotide sequence
		pSN-FXG-H-0	SEQ ID NO:6
pSN-FXG-H-1	SEQ ID NO:7
		pSN-FXG-I-0	SEQ ID NO:8
pSN-FXG-I-1	SEQ ID NO:9

Example 2 production and testing of recombinant plasmids

In this example, the construction, screening, fermentation and plasmid purification of the conventional engineering bacteria were carried out. In brief, recombinant plasmids containing the sequences SEQ ID NO 6-9 are respectively transformed into host bacteria DH5 alpha to obtain stable strains with high plasmid yield, and the strains are used as engineering bacteria for storage. Fermenting the engineering bacteria, centrifuging the obtained bacterial liquid, collecting bacterial sludge, and purifying according to a conventional plasmid purification method. Electrophoresis detection shows that the purity of the obtained 4 plasmids is more than 95%, the content of the supercoils is more than 90%, and the ratio of OD260 to OD280 is more than 1.8, which indicates that the quality of the plasmids meets the requirements. Specific test results are shown in the following table.

TABLE 3 detection results of plasmids

Example 3 detection of Gn protein expression level

1. HEK293T cell transfected by recombinant plasmid

(1) Cell preparation: HEK293T cells to be transfected were seeded in 24 wellsIn a cell culture plate, 500. mu.l/well was placed at 37 ℃ in 5% CO₂And (4) carrying out overnight culture in an incubator to ensure that the cell confluence rate is 90-95% on the day of transfection.

(2) Plasmid transfection: for each well of cells, 2 μ L Lipofectamine2000 was diluted with 50 μ L DMEM serum-free medium; for each well of cells, 50 μ l of DMEM serum-free medium was used to dilute the plasmid, and 0.8 μ g of each of the above 4 recombinant plasmids was added; after incubation at room temperature for 5min, the diluted DNA and the diluted Lipofectamine2000 were gently mixed. And incubated at room temperature for 20 min. The experimental groups were: culture medium + plasmid + transfection reagent; the negative control group was: medium + transfection reagent; the above experimental group and control group were added to the cells to be transfected at 100. mu.L/well, respectively. Adding 5% CO at 37 deg.C₂Culturing for 48h, and collecting transfection supernatant.

2. Determination of expression amount

Quantitative detection is carried out by adopting a Gn protein detection kit (purchased from Shanghai future actual products Co., Ltd., product number: JL48815-48T), the operation is carried out according to the kit instruction, finally, the light absorption value is measured at 450nm of an enzyme labeling instrument, and the content of the Gn protein is calculated and analyzed. The results are shown in Table 5.

TABLE 4.4 determination of Gn protein expression of the plasmids

As can be seen from the table, the difference in the effect of different signal peptides on the protein expression level is small, and further, when the signal peptide is the same, the truncated Gn protein expression level is more than 5 times that of the native Gn protein.

3. Determination of total and neutralizing antibody content against Gn protein in vivo

50 Balb/c mice of 6 weeks old, 20-25g, were divided into 5 groups, group 1 was a negative control group, i.e., a pSN empty plasmid administration group, and groups 2, 3, 4, and 5 were each a recombinant plasmid (pSN-FXG-H-0, pSN-FXG-H-1, pSN-FXG-I-0, and pSN-FXG-I-1) administration group. Mice were injected intramuscularly at day 0 with a plasmid dose of 10ug/0.1mL for a total of 1 injection, and blood was collected 2 weeks later, serial dilutions were made, and total antibodies to Gn protein were determined using antibody detection kit for Gn protein (purchased from UK, Inc., of Uighur, Inc., cat # JL51160-48T) according to the kit instructions. Neutralizing antibody average titer neutralizing antibody titers reducing 50% cell growth inhibition were calculated from the cell number using serially diluted antibody sera incubated with SFTSV CB1/2014 strain at room temperature for 1 hour, then incubated with Vero E6 cells in 96 well plates at 37 ℃ for 1hr, then replaced with DEME medium containing 1% fetal bovine serum and cultured for 7 days, and the results are shown in table 6.

TABLE 5 titer of antibodies

Name of plasmid	Mean titer of total antibody	Mean titer of neutralizing antibody
			Empty plasmid group	56	10
pSN-XGS-H-0	1125	82
			pSN-XGS-I-0	1254	91
pSN-XGS-H-1	6143	462
			pSN-XGS-I-1	6302	525

As can be seen from the table, the effect of the different signal peptides on the antibody titer is less different, but further, when the signal peptides are the same, the plasmids containing the nucleotide sequence encoding the truncated Gn protein induced titers of total and neutralizing antibodies against the Gn antigen significantly higher than the plasmids containing the nucleotide sequence encoding the native Gn protein.

By combining the test results, compared with the natural Gn protein, the truncated Gn protein has the advantages that the in vitro antigen expression and the expression of the total antibody and the neutralizing antibody in the induced body are all unexpectedly improved, the dosage can be greatly reduced, and the pharmacy property of the DNA vaccine can be improved.

While specific embodiments of the invention have been described in detail, those skilled in the art will understand that: various modifications and changes in detail can be made in light of the overall teachings of the disclosure, and such changes are intended to be within the scope of the present invention. A full appreciation of the invention is gained by taking the entire specification as a whole in the light of the appended claims and any equivalents thereof.

SEQUENCE LISTING

<110> Beijing Nuo Si Lande Biotechnology GmbH

<120> a truncated febrile associated thrombocytopenia syndrome virus Gn protein and uses thereof

<130> IDC210041

<160> 16

<170> PatentIn version 3.5

<210> 1

<211> 516

<212> PRT

<213> Artificial Sequence

<220>

<223> amino acid sequence of native Gn protein (without signal peptide)

<400> 1

Asp Ser Gly Pro Ile Ile Cys Ala Gly Pro Ile His Ser Asn Lys Ser

1 5 10 15

Ala Gly Ile Pro His Leu Leu Gly Tyr Ser Glu Lys Ile Cys Gln Ile

20 25 30

Asp Arg Leu Ile His Val Ser Ser Trp Leu Arg Asn His Ser Gln Phe

35 40 45

Gln Gly Tyr Val Gly Gln Arg Gly Gly Arg Ser Gln Val Ser Tyr Tyr

50 55 60

Pro Ala Glu Asn Ser Tyr Ser Arg Trp Ser Gly Leu Leu Ser Pro Cys

65 70 75 80

Asp Ala Asp Trp Leu Gly Met Leu Val Val Lys Lys Ala Lys Glu Ser

85 90 95

Asp Met Ile Val Pro Gly Pro Ser Tyr Lys Gly Lys Val Phe Phe Glu

100 105 110

Arg Pro Thr Phe Asp Gly Tyr Val Gly Trp Gly Cys Gly Ser Gly Lys

115 120 125

Ser Arg Thr Glu Ser Gly Glu Leu Cys Ser Ser Asp Ser Gly Thr Ser

130 135 140

Ser Gly Leu Leu Pro Ser Asp Arg Val Leu Trp Ile Gly Asp Val Ala

145 150 155 160

Cys Gln Pro Met Thr Pro Ile Pro Glu Glu Thr Phe Leu Glu Leu Lys

165 170 175

Ser Phe Ser Gln Ser Glu Phe Pro Asp Ile Cys Lys Ile Asp Gly Ile

180 185 190

Val Phe Asn Gln Cys Glu Gly Glu Ser Leu Pro Gln Pro Phe Asp Val

195 200 205

Ala Trp Met Asp Val Gly His Ser His Lys Ile Ile Met Arg Glu His

210 215 220

Lys Thr Lys Trp Val Gln Glu Ser Ser Ser Lys Asp Phe Val Cys Tyr

225 230 235 240

Lys Glu Gly Thr Gly Pro Cys Ser Glu Ser Glu Glu Lys Ala Cys Lys

245 250 255

Thr Ser Gly Ser Cys Arg Gly Asp Met Gln Phe Cys Lys Val Ala Gly

260 265 270

Cys Glu His Gly Glu Glu Ala Ser Glu Ala Lys Cys Arg Cys Ser Leu

275 280 285

Val His Lys Pro Gly Glu Val Val Val Ser Tyr Gly Gly Thr Arg Val

290 295 300

Arg Pro Lys Cys Tyr Gly Phe Ser Arg Met Met Ala Thr Leu Glu Val

305 310 315 320

Asn Pro Pro Glu Gln Arg Ile Gly Gln Cys Thr Gly Cys His Leu Glu

325 330 335

Cys Ile Asn Gly Gly Val Arg Leu Ile Thr Leu Thr Ser Glu Leu Arg

340 345 350

Ser Ala Thr Val Cys Ala Ser His Phe Cys Ser Ser Ala Ser Ser Gly

355 360 365

Lys Lys Ser Thr Glu Ile His Phe His Ser Gly Ser Leu Val Gly Lys

370 375 380

Thr Ala Ile His Val Lys Gly Ala Leu Val Asp Gly Thr Glu Phe Thr

385 390 395 400

Phe Glu Gly Ser Cys Met Phe Pro Asp Gly Cys Asp Ala Val Asp Cys

405 410 415

Thr Phe Cys Arg Glu Phe Leu Lys Asn Pro Gln Cys Tyr Pro Ala Lys

420 425 430

Lys Trp Leu Phe Ile Ile Ile Val Ile Leu Leu Gly Tyr Ala Gly Leu

435 440 445

Met Leu Leu Thr Asn Val Leu Lys Ala Ile Gly Val Trp Gly Ser Trp

450 455 460

Val Ile Ala Pro Val Lys Leu Met Phe Ala Ile Ile Lys Lys Leu Met

465 470 475 480

Arg Thr Val Ser Cys Leu Val Gly Lys Leu Met Asp Arg Gly Arg Gln

485 490 495

Val Ile His Glu Glu Ile Gly Glu Asn Gly Glu Gly Asn Gln Asp Asp

500 505 510

Val Arg Ile Glu

515

<210> 2

<211> 1548

<212> DNA

<213> Artificial Sequence

<220>

<223> nucleotide sequence encoding native Gn protein (without signal peptide)

<400> 2

gattcgggcc caatcatctg cgcaggaccc atccactcaa acaagagtgc tggcataccc 60

cacctgcttg gttactctga gaagatttgt cagatagatc ggctgataca tgtttcgtca 120

tggctcagga accactcgca atttcaaggc tacgttgggc agcgaggtgg acgctctcag 180

gttagctact acccagctga gaattcttac tcgaggtgga gtggacttct aagcccctgt 240

gatgctgatt ggcttgggat gcttgtcgtg aagaaggcta aggagtctga tatgatagtt 300

cctgggcctt catacaaggg gaaagtcttt tttgaacggc caacttttga tggatacgta 360

ggctggggct gtggcagtgg gaagtctagg actgagtcag gagagctctg cagttcagac 420

tcagggacaa gttctggtct tctgccctcg gatagggttc tctggatagg tgatgttgct 480

tgtcagccta tgacacccat ccctgaggag acatttctgg agctgaagag ttttagccaa 540

agtgaattcc cagacatatg taaaattgat ggcattgtgt tcaaccagtg tgagggtgag 600

agtctacccc agccctttga tgttgcatgg atggatgttg gccactctca taagatcatc 660

atgagggagc acaagaccaa atgggtacaa gagagctcat ccaaggattt tgtgtgctac 720

aaggaaggga ctggaccttg ttctgaatca gaagaaaagg cttgtaagac cagtggatca 780

tgcagagggg acatgcagtt ttgcaaggtg gcaggttgcg aacatggaga ggaggcatct 840

gaggccaagt gtagatgctc acttgtgcac aagcctgggg aagtcgttgt gtcatatgga 900

gggacgcgtg tcagaccaaa gtgctacggt ttctccagaa tgatggcaac actggaggtg 960

aacccaccag agcaaaggat tggtcaatgc actggctgcc atctagaatg cataaatggg 1020

ggtgtgaggc taatcactct aaccagtgag ctcaggtcag ctactgtctg tgcttcccac 1080

ttttgcagtt ctgcctcaag tggtaagaaa agcacggaga ttcatttcca ctcaggatca 1140

ttggttggga aaacagctat ccatgtcaaa ggggcattgg tagatggaac tgaattcaca 1200

tttgagggta gttgcatgtt cccagatgga tgtgatgcag tggactgcac attctgtcgt 1260

gagtttctaa aaaatcctca gtgctaccct gcaaagaagt ggctgttcat cattattgtc 1320

atcctccttg gatatgcagg cctcatgtta ctcaccaatg tccttaaggc aattggggtc 1380

tggggatcat gggtaatagc tccagtgaag ctaatgtttg ccatcataaa gaaactaatg 1440

agaactgtga gctgcttggt ggggaaattg atggataggg gaaggcaagt gatccatgag 1500

gaaatagggg agaatgggga gggcaaccaa gatgatgtta ggattgag 1548

<210> 3

<211> 492

<212> PRT

<213> Artificial Sequence

<220>

<223> truncated Gn protein amino acid sequence

<400> 3

Asp Ser Gly Pro Ile Ile Cys Ala Gly Pro Ile His Ser Asn Lys Ser

1 5 10 15

Ala Gly Ile Pro His Leu Leu Gly Tyr Ser Glu Lys Ile Cys Gln Ile

20 25 30

Asp Arg Leu Ile His Val Ser Ser Trp Leu Arg Asn His Ser Gln Phe

35 40 45

Gln Gly Tyr Val Gly Gln Arg Gly Gly Arg Ser Gln Val Ser Tyr Tyr

50 55 60

Pro Ala Glu Asn Ser Tyr Ser Arg Trp Ser Gly Leu Leu Ser Pro Cys

65 70 75 80

Asp Ala Asp Trp Leu Gly Met Leu Val Val Lys Lys Ala Lys Glu Ser

85 90 95

Asp Met Ile Val Pro Gly Pro Ser Tyr Lys Gly Lys Val Phe Phe Glu

100 105 110

Arg Pro Thr Phe Asp Gly Tyr Val Gly Trp Gly Cys Gly Ser Gly Lys

115 120 125

Ser Arg Thr Glu Ser Gly Glu Leu Cys Ser Ser Asp Ser Gly Thr Ser

130 135 140

Ser Gly Leu Leu Pro Ser Asp Arg Val Leu Trp Ile Gly Asp Val Ala

145 150 155 160

Cys Gln Pro Met Thr Pro Ile Pro Glu Glu Thr Phe Leu Glu Leu Lys

165 170 175

Ser Phe Ser Gln Ser Glu Phe Pro Asp Ile Cys Lys Ile Asp Gly Ile

180 185 190

Val Phe Asn Gln Cys Glu Gly Glu Ser Leu Pro Gln Pro Phe Asp Val

195 200 205

Ala Trp Met Asp Val Gly His Ser His Lys Ile Ile Met Arg Glu His

210 215 220

Lys Thr Lys Trp Val Gln Glu Ser Ser Ser Lys Asp Phe Val Cys Tyr

225 230 235 240

Lys Glu Gly Thr Gly Pro Cys Ser Glu Ser Glu Glu Lys Ala Cys Lys

245 250 255

Thr Ser Gly Ser Cys Arg Gly Asp Met Gln Phe Cys Lys Val Ala Gly

260 265 270

Cys Glu His Gly Glu Glu Ala Ser Glu Ala Lys Cys Arg Cys Ser Leu

275 280 285

Val His Lys Pro Gly Glu Val Val Val Ser Tyr Gly Gly Thr Arg Val

290 295 300

Arg Pro Lys Cys Tyr Gly Phe Ser Arg Met Met Ala Thr Leu Glu Val

305 310 315 320

Asn Pro Pro Glu Gln Arg Ile Gly Gln Cys Thr Gly Cys His Leu Glu

325 330 335

Cys Ile Asn Gly Gly Val Arg Leu Ile Thr Leu Thr Ser Glu Leu Arg

340 345 350

Ser Ala Thr Val Cys Ala Ser His Phe Cys Ser Ser Ala Ser Ser Gly

355 360 365

Lys Lys Ser Thr Glu Ile His Phe His Ser Gly Ser Leu Val Gly Lys

370 375 380

Thr Ala Ile His Val Lys Gly Ala Leu Val Asp Gly Thr Glu Phe Thr

385 390 395 400

Phe Glu Gly Ser Cys Met Phe Pro Asp Gly Cys Asp Ala Val Asp Cys

405 410 415

Thr Phe Cys Arg Glu Phe Leu Lys Asn Pro Gln Cys Tyr Pro Ala Lys

420 425 430

Lys Trp Leu Phe Ile Ile Ile Val Ile Leu Leu Gly Tyr Ala Gly Leu

435 440 445

Met Leu Leu Thr Asn Val Leu Lys Ala Ile Gly Val Trp Gly Ser Trp

450 455 460

Val Ile Ala Pro Val Lys Leu Met Phe Ala Ile Ile Lys Lys Leu Met

465 470 475 480

Arg Thr Val Ser Cys Leu Val Gly Lys Leu Met Asp

485 490

<210> 4

<211> 1548

<212> DNA

<213> Artificial Sequence

<220>

<223> optimized nucleotide sequence encoding native Gn protein (without signal peptide)

<400> 4

gactctggcc ccatcatctg tgctggcccc atccacagca acaagtctgc tggcatcccc 60

cacctgctgg gttattctga gaagatctgt cagattgaca gactgatcca tgtgagcagc 120

tggctgagaa accactctca gttccaaggc tatgtgggtc aaagaggggg cagaagccaa 180

gtgagctact accctgctga gaacagctac agcagatggt ctggccttct gagcccatgt 240

gatgctgact ggctgggcat gctggtggtg aagaaggcca aggagtctga catgattgtg 300

cctggcccta gctacaaggg caaggtgttc tttgagagac ccacctttga tggctatgtg 360

gggtggggat gtggctctgg caaaagcaga acagagtctg gggagctgtg cagctctgac 420

tctggcacaa gctctggcct gctgccctct gacagagtgc tgtggattgg ggatgttgcc 480

tgtcagccca tgacccccat ccctgaggag accttcctgg agctgaagag cttctctcag 540

tctgagttcc ctgacatctg caagattgat ggcattgtgt tcaatcagtg tgagggggag 600

agcctgcctc agccctttga tgtggcctgg atggatgtgg gccacagcca caagatcatc 660

atgagagagc acaagaccaa gtgggtgcaa gagagcagca gcaaggactt tgtgtgctac 720

aaggagggca ctggcccctg ctctgagtct gaggagaagg cctgcaagac ctctggcagc 780

tgcagagggg acatgcagtt ctgcaaggtg gctggctgtg agcatgggga ggaggcctct 840

gaggccaagt gcagatgcag cctggtgcac aagcctgggg aggtggtggt gagctatggg 900

ggcacaagag tgagacccaa gtgctatggc ttcagcagaa tgatggccac cctggaggtg 960

aacccccctg agcagagaat tgggcagtgc actggctgcc acctggagtg catcaatggg 1020

ggggtgagac tgatcaccct gacctctgag ctgagatctg ccacagtgtg tgcaagccac 1080

ttctgcagct ctgcaagctc tggcaaaaaa agcacagaga tccacttcca ctctggctcc 1140

ctggtgggca agactgctat ccatgtgaag ggggccctgg tggatggcac agagttcacc 1200

tttgagggca gctgcatgtt ccctgatggc tgtgatgctg tggactgcac cttctgcaga 1260

gagttcctga agaaccctca gtgctaccct gccaagaagt ggctgttcat catcattgtg 1320

atcctgcttg gttatgctgg actgatgctg ctgaccaatg tgctgaaggc cattggggtg 1380

tggggcagct gggtgattgc ccctgtgaag ctgatgtttg ccatcatcaa gaagctgatg 1440

agaacagtga gctgcctggt gggaaagctg atggacagag gcagacaagt gatccatgag 1500

gagattgggg agaatgggga gggcaaccaa gatgatgtga gaattgag 1548

<210> 5

<211> 1476

<212> DNA

<213> Artificial Sequence

<220>

<223> optimized nucleotide sequence encoding truncated Gn protein

<400> 5

gactctggcc ccatcatctg tgctggcccc atccacagca acaagtctgc tggcatcccc 60

cacctgctgg gttattctga gaagatctgt cagattgaca gactgatcca tgtgagcagc 120

tggctgagaa accactctca gttccaaggc tatgtgggtc aaagaggggg cagaagccaa 180

gtgagctact accctgctga gaacagctac agcagatggt ctggccttct gagcccatgt 240

gatgctgact ggctgggcat gctggtggtg aagaaggcca aggagtctga catgattgtg 300

cctggcccta gctacaaggg caaggtgttc tttgagagac ccacctttga tggctatgtg 360

gggtggggat gtggctctgg caaaagcaga acagagtctg gggagctgtg cagctctgac 420

tctggcacaa gctctggcct gctgccctct gacagagtgc tgtggattgg ggatgttgcc 480

tgtcagccca tgacccccat ccctgaggag accttcctgg agctgaagag cttctctcag 540

tctgagttcc ctgacatctg caagattgat ggcattgtgt tcaatcagtg tgagggggag 600

agcctgcctc agccctttga tgtggcctgg atggatgtgg gccacagcca caagatcatc 660

atgagagagc acaagaccaa gtgggtgcaa gagagcagca gcaaggactt tgtgtgctac 720

aaggagggca ctggcccctg ctctgagtct gaggagaagg cctgcaagac ctctggcagc 780

tgcagagggg acatgcagtt ctgcaaggtg gctggctgtg agcatgggga ggaggcctct 840

gaggccaagt gcagatgcag cctggtgcac aagcctgggg aggtggtggt gagctatggg 900

ggcacaagag tgagacccaa gtgctatggc ttcagcagaa tgatggccac cctggaggtg 960

aacccccctg agcagagaat tgggcagtgc actggctgcc acctggagtg catcaatggg 1020

ggggtgagac tgatcaccct gacctctgag ctgagatctg ccacagtgtg tgcaagccac 1080

ttctgcagct ctgcaagctc tggcaaaaaa agcacagaga tccacttcca ctctggctcc 1140

ctggtgggca agactgctat ccatgtgaag ggggccctgg tggatggcac agagttcacc 1200

tttgagggca gctgcatgtt ccctgatggc tgtgatgctg tggactgcac cttctgcaga 1260

gagttcctga agaaccctca gtgctaccct gccaagaagt ggctgttcat catcattgtg 1320

atcctgcttg gttatgctgg actgatgctg ctgaccaatg tgctgaaggc cattggggtg 1380

tggggcagct gggtgattgc ccctgtgaag ctgatgtttg ccatcatcaa gaagctgatg 1440

agaacagtga gctgcctggt gggaaagctg atggac 1476

<210> 6

<211> 1641

<212> DNA

<213> Artificial Sequence

<220>

<223> optimized nucleotide sequence encoding natural Gn protein containing HGF signal peptide

<400> 6

atgtgggtga ccaaactcct gccagccctg ctgctgcagc atgtcctcct gcatctcctc 60

ctgctcccca tcgccatccc ctatgcagag ggagactctg gccccatcat ctgtgctggc 120

cccatccaca gcaacaagtc tgctggcatc ccccacctgc tgggttattc tgagaagatc 180

tgtcagattg acagactgat ccatgtgagc agctggctga gaaaccactc tcagttccaa 240

ggctatgtgg gtcaaagagg gggcagaagc caagtgagct actaccctgc tgagaacagc 300

tacagcagat ggtctggcct tctgagccca tgtgatgctg actggctggg catgctggtg 360

gtgaagaagg ccaaggagtc tgacatgatt gtgcctggcc ctagctacaa gggcaaggtg 420

ttctttgaga gacccacctt tgatggctat gtggggtggg gatgtggctc tggcaaaagc 480

agaacagagt ctggggagct gtgcagctct gactctggca caagctctgg cctgctgccc 540

tctgacagag tgctgtggat tggggatgtt gcctgtcagc ccatgacccc catccctgag 600

gagaccttcc tggagctgaa gagcttctct cagtctgagt tccctgacat ctgcaagatt 660

gatggcattg tgttcaatca gtgtgagggg gagagcctgc ctcagccctt tgatgtggcc 720

tggatggatg tgggccacag ccacaagatc atcatgagag agcacaagac caagtgggtg 780

caagagagca gcagcaagga ctttgtgtgc tacaaggagg gcactggccc ctgctctgag 840

tctgaggaga aggcctgcaa gacctctggc agctgcagag gggacatgca gttctgcaag 900

gtggctggct gtgagcatgg ggaggaggcc tctgaggcca agtgcagatg cagcctggtg 960

cacaagcctg gggaggtggt ggtgagctat gggggcacaa gagtgagacc caagtgctat 1020

ggcttcagca gaatgatggc caccctggag gtgaaccccc ctgagcagag aattgggcag 1080

tgcactggct gccacctgga gtgcatcaat gggggggtga gactgatcac cctgacctct 1140

gagctgagat ctgccacagt gtgtgcaagc cacttctgca gctctgcaag ctctggcaaa 1200

aaaagcacag agatccactt ccactctggc tccctggtgg gcaagactgc tatccatgtg 1260

aagggggccc tggtggatgg cacagagttc acctttgagg gcagctgcat gttccctgat 1320

ggctgtgatg ctgtggactg caccttctgc agagagttcc tgaagaaccc tcagtgctac 1380

cctgccaaga agtggctgtt catcatcatt gtgatcctgc ttggttatgc tggactgatg 1440

ctgctgacca atgtgctgaa ggccattggg gtgtggggca gctgggtgat tgcccctgtg 1500

aagctgatgt ttgccatcat caagaagctg atgagaacag tgagctgcct ggtgggaaag 1560

ctgatggaca gaggcagaca agtgatccat gaggagattg gggagaatgg ggagggcaac 1620

caagatgatg tgagaattga g 1641

<210> 7

<211> 1569

<212> DNA

<213> Artificial Sequence

<220>

<223> optimized nucleotide sequence encoding truncated Gn protein containing HGF signal peptide

<400> 7

atgtgggtga ccaaactcct gccagccctg ctgctgcagc atgtcctcct gcatctcctc 60

ctgctcccca tcgccatccc ctatgcagag ggagactctg gccccatcat ctgtgctggc 120

cccatccaca gcaacaagtc tgctggcatc ccccacctgc tgggttattc tgagaagatc 180

tgtcagattg acagactgat ccatgtgagc agctggctga gaaaccactc tcagttccaa 240

ggctatgtgg gtcaaagagg gggcagaagc caagtgagct actaccctgc tgagaacagc 300

tacagcagat ggtctggcct tctgagccca tgtgatgctg actggctggg catgctggtg 360

gtgaagaagg ccaaggagtc tgacatgatt gtgcctggcc ctagctacaa gggcaaggtg 420

ttctttgaga gacccacctt tgatggctat gtggggtggg gatgtggctc tggcaaaagc 480

agaacagagt ctggggagct gtgcagctct gactctggca caagctctgg cctgctgccc 540

tctgacagag tgctgtggat tggggatgtt gcctgtcagc ccatgacccc catccctgag 600

gagaccttcc tggagctgaa gagcttctct cagtctgagt tccctgacat ctgcaagatt 660

gatggcattg tgttcaatca gtgtgagggg gagagcctgc ctcagccctt tgatgtggcc 720

tggatggatg tgggccacag ccacaagatc atcatgagag agcacaagac caagtgggtg 780

caagagagca gcagcaagga ctttgtgtgc tacaaggagg gcactggccc ctgctctgag 840

tctgaggaga aggcctgcaa gacctctggc agctgcagag gggacatgca gttctgcaag 900

gtggctggct gtgagcatgg ggaggaggcc tctgaggcca agtgcagatg cagcctggtg 960

cacaagcctg gggaggtggt ggtgagctat gggggcacaa gagtgagacc caagtgctat 1020

ggcttcagca gaatgatggc caccctggag gtgaaccccc ctgagcagag aattgggcag 1080

tgcactggct gccacctgga gtgcatcaat gggggggtga gactgatcac cctgacctct 1140

gagctgagat ctgccacagt gtgtgcaagc cacttctgca gctctgcaag ctctggcaaa 1200

aaaagcacag agatccactt ccactctggc tccctggtgg gcaagactgc tatccatgtg 1260

aagggggccc tggtggatgg cacagagttc acctttgagg gcagctgcat gttccctgat 1320

ggctgtgatg ctgtggactg caccttctgc agagagttcc tgaagaaccc tcagtgctac 1380

cctgccaaga agtggctgtt catcatcatt gtgatcctgc ttggttatgc tggactgatg 1440

ctgctgacca atgtgctgaa ggccattggg gtgtggggca gctgggtgat tgcccctgtg 1500

aagctgatgt ttgccatcat caagaagctg atgagaacag tgagctgcct ggtgggaaag 1560

ctgatggac 1569

<210> 8

<211> 1602

<212> DNA

<213> Artificial Sequence

<220>

<223> optimized nucleotide sequence encoding natural Gn protein containing IgE signal peptide

<400> 8

atggattgga catggatctt attcttagta gcagcagcaa caagagtgca ctcagactct 60

ggccccatca tctgtgctgg ccccatccac agcaacaagt ctgctggcat cccccacctg 120

ctgggttatt ctgagaagat ctgtcagatt gacagactga tccatgtgag cagctggctg 180

agaaaccact ctcagttcca aggctatgtg ggtcaaagag ggggcagaag ccaagtgagc 240

tactaccctg ctgagaacag ctacagcaga tggtctggcc ttctgagccc atgtgatgct 300

gactggctgg gcatgctggt ggtgaagaag gccaaggagt ctgacatgat tgtgcctggc 360

cctagctaca agggcaaggt gttctttgag agacccacct ttgatggcta tgtggggtgg 420

ggatgtggct ctggcaaaag cagaacagag tctggggagc tgtgcagctc tgactctggc 480

acaagctctg gcctgctgcc ctctgacaga gtgctgtgga ttggggatgt tgcctgtcag 540

cccatgaccc ccatccctga ggagaccttc ctggagctga agagcttctc tcagtctgag 600

ttccctgaca tctgcaagat tgatggcatt gtgttcaatc agtgtgaggg ggagagcctg 660

cctcagccct ttgatgtggc ctggatggat gtgggccaca gccacaagat catcatgaga 720

gagcacaaga ccaagtgggt gcaagagagc agcagcaagg actttgtgtg ctacaaggag 780

ggcactggcc cctgctctga gtctgaggag aaggcctgca agacctctgg cagctgcaga 840

ggggacatgc agttctgcaa ggtggctggc tgtgagcatg gggaggaggc ctctgaggcc 900

aagtgcagat gcagcctggt gcacaagcct ggggaggtgg tggtgagcta tgggggcaca 960

agagtgagac ccaagtgcta tggcttcagc agaatgatgg ccaccctgga ggtgaacccc 1020

cctgagcaga gaattgggca gtgcactggc tgccacctgg agtgcatcaa tgggggggtg 1080

agactgatca ccctgacctc tgagctgaga tctgccacag tgtgtgcaag ccacttctgc 1140

agctctgcaa gctctggcaa aaaaagcaca gagatccact tccactctgg ctccctggtg 1200

ggcaagactg ctatccatgt gaagggggcc ctggtggatg gcacagagtt cacctttgag 1260

ggcagctgca tgttccctga tggctgtgat gctgtggact gcaccttctg cagagagttc 1320

ctgaagaacc ctcagtgcta ccctgccaag aagtggctgt tcatcatcat tgtgatcctg 1380

cttggttatg ctggactgat gctgctgacc aatgtgctga aggccattgg ggtgtggggc 1440

agctgggtga ttgcccctgt gaagctgatg tttgccatca tcaagaagct gatgagaaca 1500

gtgagctgcc tggtgggaaa gctgatggac agaggcagac aagtgatcca tgaggagatt 1560

ggggagaatg gggagggcaa ccaagatgat gtgagaattg ag 1602

<210> 9

<211> 1530

<212> DNA

<213> Artificial Sequence

<220>

<223> optimized nucleotide sequence encoding a truncated Gn protein containing an IgE signal peptide

<400> 9

atggattgga catggatctt attcttagta gcagcagcaa caagagtgca ctcagactct 60

ggccccatca tctgtgctgg ccccatccac agcaacaagt ctgctggcat cccccacctg 120

ctgggttatt ctgagaagat ctgtcagatt gacagactga tccatgtgag cagctggctg 180

agaaaccact ctcagttcca aggctatgtg ggtcaaagag ggggcagaag ccaagtgagc 240

tactaccctg ctgagaacag ctacagcaga tggtctggcc ttctgagccc atgtgatgct 300

gactggctgg gcatgctggt ggtgaagaag gccaaggagt ctgacatgat tgtgcctggc 360

cctagctaca agggcaaggt gttctttgag agacccacct ttgatggcta tgtggggtgg 420

ggatgtggct ctggcaaaag cagaacagag tctggggagc tgtgcagctc tgactctggc 480

acaagctctg gcctgctgcc ctctgacaga gtgctgtgga ttggggatgt tgcctgtcag 540

cccatgaccc ccatccctga ggagaccttc ctggagctga agagcttctc tcagtctgag 600

ttccctgaca tctgcaagat tgatggcatt gtgttcaatc agtgtgaggg ggagagcctg 660

cctcagccct ttgatgtggc ctggatggat gtgggccaca gccacaagat catcatgaga 720

gagcacaaga ccaagtgggt gcaagagagc agcagcaagg actttgtgtg ctacaaggag 780

ggcactggcc cctgctctga gtctgaggag aaggcctgca agacctctgg cagctgcaga 840

ggggacatgc agttctgcaa ggtggctggc tgtgagcatg gggaggaggc ctctgaggcc 900

aagtgcagat gcagcctggt gcacaagcct ggggaggtgg tggtgagcta tgggggcaca 960

agagtgagac ccaagtgcta tggcttcagc agaatgatgg ccaccctgga ggtgaacccc 1020

cctgagcaga gaattgggca gtgcactggc tgccacctgg agtgcatcaa tgggggggtg 1080

agactgatca ccctgacctc tgagctgaga tctgccacag tgtgtgcaag ccacttctgc 1140

agctctgcaa gctctggcaa aaaaagcaca gagatccact tccactctgg ctccctggtg 1200

ggcaagactg ctatccatgt gaagggggcc ctggtggatg gcacagagtt cacctttgag 1260

ggcagctgca tgttccctga tggctgtgat gctgtggact gcaccttctg cagagagttc 1320

ctgaagaacc ctcagtgcta ccctgccaag aagtggctgt tcatcatcat tgtgatcctg 1380

cttggttatg ctggactgat gctgctgacc aatgtgctga aggccattgg ggtgtggggc 1440

agctgggtga ttgcccctgt gaagctgatg tttgccatca tcaagaagct gatgagaaca 1500

gtgagctgcc tggtgggaaa gctgatggac 1530

<210> 10

<211> 19

<212> PRT

<213> Artificial Sequence

<220>

<223> natural Gn protein signal peptide amino acid sequence

<400> 10

Met Met Lys Val Ile Trp Phe Ser Ser Leu Ile Cys Leu Val Ile Gln

1 5 10 15

Cys Ser Gly

<210> 11

<211> 93

<212> DNA

<213> Artificial Sequence

<220>

<223> nucleotide sequence encoding HGF signal peptide

<400> 11

atgtgggtga ccaaactcct gccagccctg ctgctgcagc atgtcctcct gcatctcctc 60

ctgctcccca tcgccatccc ctatgcagag gga 93

<210> 12

<211> 54

<212> DNA

<213> Artificial Sequence

<220>

<223> nucleotide sequence encoding IgE signal peptide

<400> 12

atggattgga catggatctt attcttagta gcagcagcaa caagagtgca ctca 54

<210> 13

<211> 31

<212> PRT

<213> Artificial Sequence

<220>

<223> amino acid sequence of HGF signal peptide

<400> 13

Met Trp Val Thr Lys Leu Leu Pro Ala Leu Leu Leu Gln His Val Leu

1 5 10 15

Leu His Leu Leu Leu Leu Pro Ile Ala Ile Pro Tyr Ala Glu Gly

20 25 30

<210> 14

<211> 18

<212> PRT

<213> Artificial Sequence

<220>

<223> amino acid sequence of IgE signal peptide

<400> 14

Met Asp Trp Thr Trp Ile Leu Phe Leu Val Ala Ala Ala Thr Arg Val

1 5 10 15

His Ser

<210> 15

<211> 523

<212> PRT

<213> Artificial Sequence

<220>

<223> amino acid sequence of truncated Gn protein containing HGF signal peptide

<400> 15

Met Trp Val Thr Lys Leu Leu Pro Ala Leu Leu Leu Gln His Val Leu

1 5 10 15

Leu His Leu Leu Leu Leu Pro Ile Ala Ile Pro Tyr Ala Glu Gly Asp

20 25 30

Ser Gly Pro Ile Ile Cys Ala Gly Pro Ile His Ser Asn Lys Ser Ala

35 40 45

Gly Ile Pro His Leu Leu Gly Tyr Ser Glu Lys Ile Cys Gln Ile Asp

50 55 60

Arg Leu Ile His Val Ser Ser Trp Leu Arg Asn His Ser Gln Phe Gln

65 70 75 80

Gly Tyr Val Gly Gln Arg Gly Gly Arg Ser Gln Val Ser Tyr Tyr Pro

85 90 95

Ala Glu Asn Ser Tyr Ser Arg Trp Ser Gly Leu Leu Ser Pro Cys Asp

100 105 110

Ala Asp Trp Leu Gly Met Leu Val Val Lys Lys Ala Lys Glu Ser Asp

115 120 125

Met Ile Val Pro Gly Pro Ser Tyr Lys Gly Lys Val Phe Phe Glu Arg

130 135 140

Pro Thr Phe Asp Gly Tyr Val Gly Trp Gly Cys Gly Ser Gly Lys Ser

145 150 155 160

Arg Thr Glu Ser Gly Glu Leu Cys Ser Ser Asp Ser Gly Thr Ser Ser

165 170 175

Gly Leu Leu Pro Ser Asp Arg Val Leu Trp Ile Gly Asp Val Ala Cys

180 185 190

Gln Pro Met Thr Pro Ile Pro Glu Glu Thr Phe Leu Glu Leu Lys Ser

195 200 205

Phe Ser Gln Ser Glu Phe Pro Asp Ile Cys Lys Ile Asp Gly Ile Val

210 215 220

Phe Asn Gln Cys Glu Gly Glu Ser Leu Pro Gln Pro Phe Asp Val Ala

225 230 235 240

Trp Met Asp Val Gly His Ser His Lys Ile Ile Met Arg Glu His Lys

245 250 255

Thr Lys Trp Val Gln Glu Ser Ser Ser Lys Asp Phe Val Cys Tyr Lys

260 265 270

Glu Gly Thr Gly Pro Cys Ser Glu Ser Glu Glu Lys Ala Cys Lys Thr

275 280 285

Ser Gly Ser Cys Arg Gly Asp Met Gln Phe Cys Lys Val Ala Gly Cys

290 295 300

Glu His Gly Glu Glu Ala Ser Glu Ala Lys Cys Arg Cys Ser Leu Val

305 310 315 320

His Lys Pro Gly Glu Val Val Val Ser Tyr Gly Gly Thr Arg Val Arg

325 330 335

Pro Lys Cys Tyr Gly Phe Ser Arg Met Met Ala Thr Leu Glu Val Asn

340 345 350

Pro Pro Glu Gln Arg Ile Gly Gln Cys Thr Gly Cys His Leu Glu Cys

355 360 365

Ile Asn Gly Gly Val Arg Leu Ile Thr Leu Thr Ser Glu Leu Arg Ser

370 375 380

Ala Thr Val Cys Ala Ser His Phe Cys Ser Ser Ala Ser Ser Gly Lys

385 390 395 400

Lys Ser Thr Glu Ile His Phe His Ser Gly Ser Leu Val Gly Lys Thr

405 410 415

Ala Ile His Val Lys Gly Ala Leu Val Asp Gly Thr Glu Phe Thr Phe

420 425 430

Glu Gly Ser Cys Met Phe Pro Asp Gly Cys Asp Ala Val Asp Cys Thr

435 440 445

Phe Cys Arg Glu Phe Leu Lys Asn Pro Gln Cys Tyr Pro Ala Lys Lys

450 455 460

Trp Leu Phe Ile Ile Ile Val Ile Leu Leu Gly Tyr Ala Gly Leu Met

465 470 475 480

Leu Leu Thr Asn Val Leu Lys Ala Ile Gly Val Trp Gly Ser Trp Val

485 490 495

Ile Ala Pro Val Lys Leu Met Phe Ala Ile Ile Lys Lys Leu Met Arg

500 505 510

Thr Val Ser Cys Leu Val Gly Lys Leu Met Asp

515 520

<210> 16

<211> 510

<212> PRT

<213> Artificial Sequence

<220>

<223> amino acid sequence of truncated Gn protein containing IgE signal peptide

<400> 16

Met Asp Trp Thr Trp Ile Leu Phe Leu Val Ala Ala Ala Thr Arg Val

1 5 10 15

His Ser Asp Ser Gly Pro Ile Ile Cys Ala Gly Pro Ile His Ser Asn

20 25 30

Lys Ser Ala Gly Ile Pro His Leu Leu Gly Tyr Ser Glu Lys Ile Cys

35 40 45

Gln Ile Asp Arg Leu Ile His Val Ser Ser Trp Leu Arg Asn His Ser

50 55 60

Gln Phe Gln Gly Tyr Val Gly Gln Arg Gly Gly Arg Ser Gln Val Ser

65 70 75 80

Tyr Tyr Pro Ala Glu Asn Ser Tyr Ser Arg Trp Ser Gly Leu Leu Ser

85 90 95

Pro Cys Asp Ala Asp Trp Leu Gly Met Leu Val Val Lys Lys Ala Lys

100 105 110

Glu Ser Asp Met Ile Val Pro Gly Pro Ser Tyr Lys Gly Lys Val Phe

115 120 125

Phe Glu Arg Pro Thr Phe Asp Gly Tyr Val Gly Trp Gly Cys Gly Ser

130 135 140

Gly Lys Ser Arg Thr Glu Ser Gly Glu Leu Cys Ser Ser Asp Ser Gly

145 150 155 160

Thr Ser Ser Gly Leu Leu Pro Ser Asp Arg Val Leu Trp Ile Gly Asp

165 170 175

Val Ala Cys Gln Pro Met Thr Pro Ile Pro Glu Glu Thr Phe Leu Glu

180 185 190

Leu Lys Ser Phe Ser Gln Ser Glu Phe Pro Asp Ile Cys Lys Ile Asp

195 200 205

Gly Ile Val Phe Asn Gln Cys Glu Gly Glu Ser Leu Pro Gln Pro Phe

210 215 220

Asp Val Ala Trp Met Asp Val Gly His Ser His Lys Ile Ile Met Arg

225 230 235 240

Glu His Lys Thr Lys Trp Val Gln Glu Ser Ser Ser Lys Asp Phe Val

245 250 255

Cys Tyr Lys Glu Gly Thr Gly Pro Cys Ser Glu Ser Glu Glu Lys Ala

260 265 270

Cys Lys Thr Ser Gly Ser Cys Arg Gly Asp Met Gln Phe Cys Lys Val

275 280 285

Ala Gly Cys Glu His Gly Glu Glu Ala Ser Glu Ala Lys Cys Arg Cys

290 295 300

Ser Leu Val His Lys Pro Gly Glu Val Val Val Ser Tyr Gly Gly Thr

305 310 315 320

Arg Val Arg Pro Lys Cys Tyr Gly Phe Ser Arg Met Met Ala Thr Leu

325 330 335

Glu Val Asn Pro Pro Glu Gln Arg Ile Gly Gln Cys Thr Gly Cys His

340 345 350

Leu Glu Cys Ile Asn Gly Gly Val Arg Leu Ile Thr Leu Thr Ser Glu

355 360 365

Leu Arg Ser Ala Thr Val Cys Ala Ser His Phe Cys Ser Ser Ala Ser

370 375 380

Ser Gly Lys Lys Ser Thr Glu Ile His Phe His Ser Gly Ser Leu Val

385 390 395 400

Gly Lys Thr Ala Ile His Val Lys Gly Ala Leu Val Asp Gly Thr Glu

405 410 415

Phe Thr Phe Glu Gly Ser Cys Met Phe Pro Asp Gly Cys Asp Ala Val

420 425 430

Asp Cys Thr Phe Cys Arg Glu Phe Leu Lys Asn Pro Gln Cys Tyr Pro

435 440 445

Ala Lys Lys Trp Leu Phe Ile Ile Ile Val Ile Leu Leu Gly Tyr Ala

450 455 460

Gly Leu Met Leu Leu Thr Asn Val Leu Lys Ala Ile Gly Val Trp Gly

465 470 475 480

Ser Trp Val Ile Ala Pro Val Lys Leu Met Phe Ala Ile Ile Lys Lys

485 490 495

Leu Met Arg Thr Val Ser Cys Leu Val Gly Lys Leu Met Asp

500 505 510

Claims

1. A Gn protein of truncated febrile with thrombocytopenia syndrome bunyavirus (SFTSV) C-terminally truncated by 24 amino acids compared to the native Gn protein;

preferably, the SFTSV is C1, C2, C3, C4, C5, J1, J2, J3 genotype;

preferably, the SFTSV is a clinical isolate of SFTSV, such as an isolate selected from: SFTSV HB29/China/2010, SFTSV CB1/South Korea/2014, SFTSV KAJNH2/South Korea/2013, SFTSV ZJZHSH-FDE/China/2012, SFTSV KADGH/South Korea/2013, SFTSV SPL035A/Japan, SFTSV SPL032A/Japan, SFTSV SPL 004A/Japan;

preferably, the amino acid sequence of the Gn protein of the fever with thrombocytopenia syndrome bunyavirus is shown as SEQ ID NO. 1;

preferably, the amino acid sequence of the natural Gn protein is shown as SEQ ID NO 1;

preferably, the amino acid sequence of the truncated Gn protein is shown in SEQ ID NO 3.

2. A fusion protein comprising the truncated Gn protein of claim 1 and an additional polypeptide;

preferably, the fusion protein is not a naturally occurring protein or fragment thereof;

preferably, said further polypeptide is heterologous with respect to said truncated Gn protein;

preferably, the further polypeptide is linked to the N-terminus or C-terminus of the truncated Gn protein, optionally via a linker (e.g. a peptide linker);

preferably, the additional polypeptide is selected from a tag, a signal peptide or a leader, a detectable label (e.g., luciferase (fluc), Green Fluorescent Protein (GFP)), or any combination thereof;

preferably, the signal peptide is selected from the group consisting of a native signal peptide of Gn protein, a native signal peptide of HGF (hepatocyte growth factor) and a native signal peptide of IgE (immunoglobulin E);

preferably, the signal peptide has an amino acid sequence selected from the group consisting of: 10, 13, and 14;

preferably, the fusion protein has an amino acid sequence selected from the group consisting of: 15 and 16.

3. A nucleic acid molecule comprising a nucleotide sequence encoding the truncated Gn protein of claim 1 or the fusion protein of claim 2;

preferably, the nucleotide sequence encoding the truncated Gn protein or fusion protein is codon optimized or non-optimized according to the codon preference of the host cell (e.g., human cell);

preferably, the nucleic acid molecule has a nucleotide sequence selected from the group consisting of: 5, 7, and 9;

preferably, the nucleic acid molecule is DNA.

4. A vector comprising the nucleic acid molecule of claim 3;

preferably, the vector is selected from the group consisting of plasmids; phagemid; a cosmid; artificial chromosomes such as Yeast Artificial Chromosomes (YACs), Bacterial Artificial Chromosomes (BACs), or artificial chromosomes (PACs) derived from P1; bacteriophages such as lambda bacteriophage or M13 bacteriophage; and, viral vectors, such as retroviral vectors (e.g., lentiviral vectors), adenoviral vectors, adeno-associated viral vectors, herpes viral vectors (e.g., herpes simplex viral vectors), poxvirus vectors, baculovirus vectors, papilloma viral vectors, papilloma polyomavirus vectors;

preferably, the vector is for expressing (e.g., expressing in vivo in a subject (e.g., a mammal, such as a human)) the truncated Gn protein or the fusion protein;

preferably, the vector is a vector for gene therapy, such as a plasmid, an adenovirus vector, an adeno-associated virus vector, and a lentivirus vector.

5. A host cell comprising the nucleic acid molecule of claim 3 or the vector of claim 4;

preferably, the host cell is selected from prokaryotic cells, such as e.coli cells, and eukaryotic cells, such as yeast cells, insect cells, plant cells and animal cells (e.g., mammalian cells, such as mouse cells, human cells, etc.);

preferably, the host cell is an E.coli cell, such as E.coli DH5 alpha cell; alternatively, the host cell is a human cell (e.g., 293T cell).

6. A method of expressing or producing a truncated Gn protein according to claim 1 or a fusion protein according to claim 2, the method comprising using a nucleic acid molecule according to claim 3 or a vector according to claim 4 or a host cell according to claim 5;

preferably, the method comprises expressing the nucleic acid molecule according to claim 3 or the vector according to claim 4 in a host cell under conditions that allow the expression of the protein; and optionally, recovering the truncated Gn protein or the fusion protein expressed in the host cell.

7. Use of a nucleic acid molecule according to claim 3 or a vector according to claim 4 or a host cell according to claim 5 for expressing or producing the truncated Gn protein or the fusion protein;

for example, said nucleic acid molecule or vector is used for the expression or production of said truncated Gn protein or said fusion protein in vitro;

for example, said nucleic acid molecule or vector is for expressing or producing said truncated Gn protein or said fusion protein in a cell;

for example, the nucleic acid molecule or vector is used to express or produce the truncated Gn protein or the fusion protein in vitro, in a cell.

8. A pharmaceutical composition comprising a truncated Gn protein according to claim 1 or a fusion protein according to claim 2 or a nucleic acid molecule according to claim 3 or a vector according to claim 4, and optionally a pharmaceutically acceptable carrier and/or excipient;

preferably, the pharmaceutical composition is administered by injection;

preferably, the pharmaceutical composition is an injection or a lyophilized powder;

preferably, the truncated Gn protein or fusion protein or nucleic acid molecule or vector is present in an effective amount (e.g., a prophylactically or therapeutically effective amount);

preferably, the pharmaceutical composition is in unit dosage form.

9. The pharmaceutical composition of claim 8, wherein the pharmaceutical composition is a vaccine;

preferably, the pharmaceutical composition further comprises an adjuvant;

preferably, the pharmaceutical composition is a protein vaccine comprising a truncated Gn protein according to claim 1 or a fusion protein according to claim 2;

preferably, the pharmaceutical composition is a nucleic acid vaccine comprising the nucleic acid molecule of claim 3 or the vector of claim 4;

preferably, the nucleic acid vaccine is a DNA vaccine.

10. A method of preparing the pharmaceutical composition of claim 8, the method comprising mixing the truncated Gn protein of claim 1 or the fusion protein of claim 2 or the nucleic acid molecule of claim 3 or the vector of claim 4 with a pharmaceutically acceptable carrier and/or excipient (e.g., adjuvant).

11. Use of a truncated Gn protein according to claim 1 or a fusion protein according to claim 2 or a nucleic acid molecule according to claim 3 or a vector according to claim 4 in the manufacture of a pharmaceutical composition for use in the prevention or treatment of SFTSV infection or a disease caused by SFTSV infection (e.g. SFTS) in a subject;

preferably, the subject is a mammal, e.g., a human;

preferably, the pharmaceutical composition is administered by injection;

preferably, the pharmaceutical composition comprises an effective amount (e.g., an effective amount to prevent or treat SFTSV infection or a disease caused by SFTSV infection (e.g., SFTS)) of the truncated Gn protein or fusion protein or nucleic acid molecule or vector;

preferably, the pharmaceutical composition is in unit dosage form;

preferably, the pharmaceutical composition is a vaccine;

preferably, the pharmaceutical composition further comprises an adjuvant;

preferably, the pharmaceutical composition is a protein vaccine comprising a truncated Gn protein as described above or a fusion protein as described above;

preferably, the pharmaceutical composition is a nucleic acid vaccine comprising a nucleic acid molecule as described above or a vector as described above;

preferably, the nucleic acid vaccine is a DNA vaccine.

12. A viroid particle comprising a truncated Gn protein according to claim 1 or comprising a fusion protein according to claim 2; alternatively, the viroid consists of a Gn protein according to claim 1 or a fusion protein comprising a protein according to claim 2.

13. A method of preventing or treating SFTSV infection or a disease caused by SFTSV infection (e.g., SFTS) in a subject, comprising administering to a subject in need thereof an effective amount of a truncated Gn protein of claim 1 or a fusion protein of claim 2 or a nucleic acid molecule of claim 3 or a vector of claim 4 or a pharmaceutical composition of claim 8 or 9;

preferably, the subject is a mammal, e.g., a human;

preferably, the truncated Gn protein or the fusion protein or the nucleic acid molecule or the vector or the pharmaceutical composition is administered to the subject by injection.