A kind of artificial synthesized promoter PMP1 of phytophthora inductivity and its recombinant expression carrier and
Using
Technical field
The invention belongs to field of biotechnology, it is related to a kind of artificial synthesized promoter PMP1 of phytophthora inductivity and its recombination table
Up to the application of carrier and the phytophthora inducible promoter, recombinant expression carrier.
Background technique
Effectively control the key problem that plant disease is always Plant Pathology research.For a long time, using chemical pesticide
It is the major technique of Disease management, but problems faced is in practical applications: on the one hand lacks effective medicament, on the other hand
The problems such as adjoint phytotoxicity during medication, environmental pollution.It is proposed resistant breeding strategy again later, but because its period is long,
The a series of problems such as at high cost, scale is big, and precision is low, are difficult to be promoted and applied.With molecular biology and biological skill
The development of art further provides the strategy of resistant gene engineering, but adjoint problem is: when constructive expression one defence is anti-
When answering related gene, it is difficult to control the precision of gene expression, often will affect the normal growth and development of plant.And cause of disease induces
Property promoter may provide new hope to solve this problem, because pathogen-inducible promoter can accurately be adjusted on space-time
Gene is controlled in Infected with Pathogenic Fungi point specifically expressing.
Phytophthora (Phytophthora) is identified at present more than 100 kinds, and most of in them are pathogenic
Bacterium, caused plant disease is popular and crushing often with having, therefore referred to as epidemic disease.In production, the master of phytophthora blight is controlled
Wanting method is breeding resistant variety, but with the tachytelic evolution and variation of phytophthora genome, the resistance of disease-resistant variety also can be short
It is lost in time.Therefore, Genes For Plant Tolerance phytophthora genetic engineering is also faced with huge challenge.It is clear that function is also lacked in production at present
There is the phytophthora inducible promoter of application potential in Chu.Therefore disease-resistant transgenic engineering strategy, artificial synthesized phytophthora induction out are utilized
Property promoter, will provide valuable promoter for plant resistant to phytophthora root rot genetic engineering.
Summary of the invention
Present invention aim to address in the prior art it is complicated to phytophthora disease control method, control effect is unobvious,
And the problem of lacking available pathogen-inducible promoter in novel resistant gene engineering technology, a kind of phytophthora induction is provided
Property promoter.The promoter obtains a novel cis- member from the analysis to 180 phytophthora inducible promoter sequences
Part extracts the flanking sequence of cis element AAACTA and its each 12bp of upstream and downstream, the sequence of total 30bp, artificial synthesized tetramer shape
At promoter PMP1, by promoter building in plant expression vector pMDC162, driving that can be special under the induction of phytophthora
The up-regulated expression of downstream gus reporter gene.
Another object of the present invention is to provide the recombinant expression carrier containing above-mentioned phytophthora inducible promoter, turn base
Because of cell line and transgenosis recombinant bacterium.
Another object of the present invention is to provide the application of above-mentioned phytophthora inducible promoter and its recombinant expression carrier.
The purpose of the present invention is achieved through the following technical solutions:
A kind of phytophthora inducible promoter PMP1, the promoter are with AAACTA cis element and its each 12bp of upstream and downstream
Flanking sequence (sequence of total 30bp) is core sequence.Preferably, the flanking sequence of upstream is CAACAGTGATTA, the side in downstream
Wing sequence is GAACCCAAAATC.The promoter can quickly drive the upper mileometer adjustment of gene downstream in the case where phytophthora infects
It reaches, that is, is constructed in the upstream of gus reporter gene, the expression of gus reporter gene can be driven under the induction of phytophthora.
Select gus reporter gene in conjunction with phytophthora inducible promoter, conducive to this of detection phytophthora inducible promoter
Pathogenic bacterium inducing expression characteristic;Certainly, if using the available reporter gene of any field of biotechnology and the phytophthora inductivity
Promoter combines, and can reach same purpose, such as green fluorescent protein GFP etc..
The tetramer of artificial synthesized above-mentioned core sequence forms phytophthora inducible promoter PMP1, i.e. the promoter is above-mentioned
The tetramer of core sequence, comprising there are four duplicate cis element AAACTA, each cis element AAACTA or more
Trip respectively has the flanking sequence of 12bp.
Preferably, the sequence of phytophthora inducible promoter PMP1 is as shown in SEQ ID NO.5.
A kind of nucleotide sequence, be in the nucleotide sequence include above-mentioned phytophthora inducible promoter sequence
Column.
Recombinant expression carrier, transgenic cell line and transgenosis recombinant bacterium containing above-mentioned phytophthora inducible promoter.
Above-mentioned recombinant expression carrier is that the recombinant expression carrier is by the sequence of above-mentioned phytophthora inducible promoter
In the reporter gene upstream of plant expression vector, the phytophthora inducible promoter can be under the induction of phytophthora for column building
Drive the expression of reporter gene.Reporter gene used in the present invention is gus reporter gene, but not limited to this.Institute of the present invention
The plant expression vector used is pMDC162.But artificial synthesized phytophthora inducible promoter sequence has uniqueness, plant
Expression vector is not uniquely that the plant expression vector pMDC162 that the present invention enumerates is that one kind is particularly suited for the present invention
The conversion of the target gene of offer.
Above-mentioned phytophthora inducible promoter answering on recombinant expression carrier of the building containing phytophthora inducible promoter
With.
Application of the above-mentioned phytophthora inducible promoter in the genetically modified plants that building has phytophthora inducing expression.Institute
The genetically modified plants stated are preferably tobacco.
Above-mentioned nucleotide sequence or the recombinant expression carrier containing phytophthora inducible promoter are being constructed with phytophthora
Application in the genetically modified plants of inducing expression.
The present invention is based on 2888 genetic chips of soybean, pass through 180 phytophthora inducible genes of bioinformatic analysis
Promoter region is obtained according to the frequency of occurrences of cis-structure element, position distribution and relationship with inducible gene expression amount
Core sequence is the novel cisacting element of AAACTA.Take the cis element and its each 12bp up and down in gene promoter
Flanking sequence, the sequence of total 30bp, artificial synthesized tetramer sequences merge gus reporter gene as promoter PMP1, by PMP1
It is building up in plant expression vector pMDC162, and passes through the tobacco transient expression system of mediated by agriculture bacillus, to the cause of disease of promoter
Bacterium inducing expression characteristic is analyzed.As a result, it has been found that artificial synthesized PMP1 promoter can be under the induction of phytophthora quickly, efficiently
Driving gus reporter gene up-regulation inducing expression.It can be seen that artificial synthesized PMP1 promoter is pathogen-inducible starting
Son provides valuable pathogen-inducible promoter for Genes For Plant Tolerance phytophthora genetic engineering.
Beneficial effects of the present invention:
1. inventor, by a large number of experiments, discovery derives from induction of the artificial synthesized promoter of soybean by phytophthora, energy
The fast upregulation expression of special driving downstream gene.Therefore, which has stronger in Genes For Plant Tolerance phytophthora genetic engineering
Application potential.
2. since pathogen infection speed is very fast, if it is possible to make to be infected its defense response genes of plant quick start
Expression, to improve its disease resistance be most important.The present invention passes through test, it was demonstrated that impregnates inoculation with phytophthora parasitica zoospore
The artificial synthesized promoter and its recombinant expression carrier of method processing transient expression, can 2h after inoculation detect report
Accuse quick, the high-intensitive expression of gene.Illustrate that artificial synthesized promoter PMP1 is a phytophthora inducible promoter.
3. being expressed as follows recombinant plasmid in tobacco in advance: by the PMP1::GUS of PMP1 promoter fusion gus reporter gene
Recombinant plasmid.It is inoculated with phytophthora parasitica Ppo25 after 72h, the expression of reporter gene fast upregulation can be driven by 2h after infecting.Illustrate people
The promoter PMP1 of work synthesis is pathogen-inducible promoter.The promoter can be expressed in tobacco transient expression system, in epidemic disease
The up-regulated expression of fast driving downstream gus reporter gene under mould induction provides valuable disease for Genes For Plant Tolerance phytophthora genetic engineering
Former inducible promoter becomes the candidate material of Genes For Plant Tolerance phytophthora genetic engineering, further can be lasting to be provided in production
The breeding material of disease-resistant potentiality.
Detailed description of the invention
The novel cis element that Fig. 1 is obtained is with the relationship (A) of phytophthora expression profile expression quantity and in promoter
It positions (B)
Two groups will be divided by 180 genes that phytophthora specificity induces in genetic chip: being one containing the sequential element
Group and be another group without the cis element.Then this two groups of genes inducing expression amount after inoculation phytophthora one day is compared to increase
Multiple.As can be seen that containing the one group higher by phytophthora inducing expression multiple of an AAACTA cis element from Figure 1A.Figure
1B:AAACTA cis element appears in position and its distribution in gene promoter.
Fig. 2 constructs the recombinant plant expression vector pMDC162 schematic diagram of artificial synthesized phytophthora inducible promoter
Four " motif " in figure are indicated: upstream and downstream is each by novel sequential element AAACTA and its in gene promoter
12bp flanking sequence forms four repetitive units as one " motif ", by " motif " in the form of concatenated, closes as artificial
At promoter PMP1, the area is inserted into after Kpn I and BgL II double digestion." 35S min " is composing type CaMV35S promoter
In -46~+8 regions.Ultimately form the pMDC162 weight of artificial synthesized PMP1 promoter fusion 35S min and gus reporter gene
Group plant expression vector.
Fig. 3 detects the change of artificial synthesized promoter PMP1 driving gus reporter gene expression in tobacco Transient Expression System
Learn tissue staining result
Artificial synthesized PMP1 promoter in figure, constructive expression's strong promoter (positive control) cannot drive gene expression
Minimal promoter (negative control) respectively on tobacco express 3d after, with Phytophthora capsici P.c35 zoospore (105A/mL) it connects
Kind, and the activity of the method detection gus reporter gene of 0h and the chemical tissue staining of 2h after inoculation.
Fig. 4 detects the enzyme of artificial synthesized promoter PMP1 driving gus reporter gene expression in tobacco Transient Expression System
Living and mRNA detection
A. artificial synthesized PMP1 promoter, after expressing 3d on tobacco, with Phytophthora capsici P.c35 zoospore (105A/
ML it) is inoculated with, and the enzymatic activity of 0h and 2h detection gus reporter gene after inoculation.
B. artificial synthesized PMP1 promoter, after expressing 3d on tobacco, with Phytophthora capsici P.c35 zoospore (105A/
ML it) is inoculated with, and the table of the method detection gus reporter gene transcriptional level of 0h and 2h real-time fluorescence quantitative PCR after inoculation
It reaches.
Specific embodiment
Below with reference to embodiment, the present invention will be further described, and the experiment side of actual conditions is not specified in the following example
Method, usually according to the known approaches of this field.
The acquisition of 1 novel cis element AAACTA of embodiment
1. screening the special induced gene promoter structure element of phytophthora according to chip data
According to three different soybean varieties: V71-370, VPRIL9, Sloan are by soybean phytophthora infection processs full genome table
Up to chip data document (Zhou L, Mideros SX, Bao L, the et al.Infection and genotype of spectrum
Remodel the entire soybean transcriptome [J] .BMC Genomics, 2009,10 (1): 49-59.),
Analyze the promoter region of 180 up-regulated expression genes after soybean phytophthora infects involved in the document.We collect first
Some functional element sequences registered search frequency and its position distribution that these sequences occur in this 180 genes,
And the expression of 1d is compared with without the promoters of these elements after inoculation by the promoter containing these elements.So
Position distribution of these elements of post analysis in respective promoter.And selecting for new structural detail, standard of the invention
It is that the frequency of occurrences is apparently higher than other its genes in the promoter for the gene that phytophthora specifically induces, and in three kinds
In soybean, the gene without the element will be apparently higher than by being inoculated with the case where gene upregulation after phytophthora 1d containing the element is expressed.
2. cis element signature analysis
According to the frequency of occurrences of cis-structure element, position distribution and relationship with inducible gene expression amount.Starting
Cis element usually contains 5~9 bases in son, we all list the various combination of 5,6,7,8,9 bases, then seeks
The frequency for looking for every kind of base composition to occur in 180 phytophthora specificity induced genes, and 180 are selected in soybean genome
Gene, the frequency that every kind of base composition of analysis occurs in 180 genes, compared with the frequency that known sequence element occurs
Obtain conspicuousness.The base composition of picking P≤0.01 analyzes its pass with expression quantity with the method for analyzing known cis element
System, and select in three soybean varieties, the consistent base composition of expression quantity variation tendency.By analyzing above, we obtain altogether
Obtain 25 new cis elements.
It is involved in the present invention to novel cis element AAACTA be one of those, when in gene contain the cis element
When, phytophthora inducing expression amount, which is higher than, is free of the cis element gene, accordingly it is presumed that these cis elements may be in soybean
Gene plays an important role in terms of by phytophthora inducing expression, the result is shown in Figure 1 A.And Figure 1B is then each structural detail in promoter
The statistics of position, the cis element are distributed no apparent taxis in gene promoter.
The artificial synthesized PMP1 promoter of embodiment 2 is phytophthora inducible promoter
1. synthesis and the vector construction of Artificial promoters
By the flank sequence of each 12bp of novel cis element AAACTA and its upstream and downstream obtained by bioinformatic analysis
Column, four repetitive units of total 30bp, this artificial synthesized 30bp, sequence (such as SEQ ID as artificial synthesized promoter PMP1
Shown in NO.5), for constructing plant expression vector.
According to Chai C, Lin Y, Shen D, et al.Identification and Functional
Characterization of the Soybean GmaPPO12Promoter Conferring Phytophthora
2013,8 (6): sojae Induced Expression [J] .PloS One constructs promoter fusion GUS report in 1-6. article
The plant expression vector method for accusing gene is obtained by the PMP1::GUS recombinant plasmid of four repetitive unit fusion gus reporter genes,
The forming types figure of carrier is as shown in Figure 2.
2. the Ben Shi cigarette transient expression of mediated by agriculture bacillus and inoculation
The plant expression vector pMDC162 of PMP1::GUS recombinant plasmid is transferred to GV3101 agriculture bar by electrotransformation technology
(Plant Transformation that the bacterial strain is known to the skilled person often uses bacterial strain to bacterium (Biovector) bacterial strain, and Agricultural University Of Nanjing is big
Beans phytophthora and plant interaction laboratory save) in, the positive transformant of Agrobacterium is added into kanamycins (50 μ g/mL) in 3ml
LB culture solution in, 220rpm, 28-30 DEG C of culture 48h, 4000rpm are centrifuged 4min, thallus are collected, with 10mM MgCl2It is resuspended,
After in triplicate, with 10mM MgCl2It is settled to 600=0.4~0.6 OD.Take 6-8 weeks tobacco of growth, from upper several thirds to
6th true leaf being fully deployed be used to permeate inoculation Agrobacterium.A minor cut or wound is caused in tobacco lower epidermis with syringe needle, uses 1mL
The syringe of needle-less penetrates into 30-50 μ L Agrobacterium suspension in Ben's Tobacco Leaves.72h is inoculated with after injection.Cut injection
Tobacco leaf is immersed in Phytophthora capsici spore suspension, spore concentration 105A/mL, 0 and 2h takes after inoculation respectively
Sample uses rapidly liquid nitrogen cryopreservation, in case detection GUS enzymatic activity, or dyed with being immersed in GUS dye liquor for GUS.Experiment repeats three
It is secondary, three biology are set every time and are repeated, for detecting the Reporter gene GUS of the phytophthora inducing expression in tobacco Transient Expression System
Activity.
3.GUS activity analysis
3.1 GUS chemistry tissue stainings
The methods of reference Jefferson (Jefferson RA, Kavanagh TA, Bevan MW.GUS fusions:
beta-glucuronidase as a sensitive and versatile gene fusion marker in higher
Plants [J] .EMBO J, 1987,6 (13): 3901-3907.) measurement tobacco leaf and the gus reporter gene in Gen Mao table
It reaches.The blade (from the specimen material of example 2) dyed will be needed to be immersed in GUS dye liquor (50mmol L-1Sodium phosphate buffer
PH 7.0,10mol L-1EDTA, 1mmol L-1X-Gluc, 0.1%Triton X-100,10mmol L-1Beta -mercaptoethanol) in,
It is placed in 37 DEG C of incubation 12h, 75% ethyl alcohol rinses twice, then uses 95% ethanol decolorization, up to background color completely disappears.Respectively in tobacco
After upper expression 3d, with Phytophthora capsici P.c35 zoospore (105A/mL) inoculation, and the chemistry tissue of 0 and 2h after inoculation
The activity of the method detection gus reporter gene of dyeing.The chemical tissue staining of recombinant plasmid transient expression tobacco is shown in Fig. 3
As a result, the results showed that PMP1 promoter can drive the expression of reporter gene on the tobacco leaf of instantaneous conversion, show as dyeing
Blue depth it is deeper than the color with 0h in 2h;The intensity of positive control has almost been approached in the intensity of 2h GUS dyeing, and
There is no color change in negative control.
3.2 GUS Enzyme activity assays
The material of GUS enzymatic activity will be needed to measure: blade (from the specimen material of example 2) about 100mg is set in mortar
500 μ L (50mM NaH of Extraction buffer is added in liquid feeding nitrogen grind into powder2PO4, pH 7.0,10mM EDTA, 0.1%Triton
X-100,0.1 (w/v) dodecyl sodium sulfate, 10mM beta -mercaptoethanol), 4 DEG C of centrifugations, supernatant is gus protein extracting solution.With
BSA method measures protein concentration.Part plus GUS reaction substrate 4-MUG are taken out, in 37 DEG C of reaction 30min, is sent out in exciting light 365nm
It penetrates under conditions of light 455nm and carries out fluoremetry, 3 secondary pollutants repeat, finally with the relative variation of product in the unit time
To calculate the enzymatic activity value of gus reporter gene.Recombinant plasmid transient expression tobacco detection gus reporter gene is shown in Fig. 4-A
Enzyme activity the result shows that, compared with nonvaccinated sample, PMP1 promoter can after inoculation 2h driving reporter gene on mileometer adjustment
Up to 8.1 times.
The detection of 3.3 GUS mRNA
As object, the method for using real-time fluorescence quantitative PCR is detected to detect GUS the material obtained in 2 method 2 of embodiment
The expression of reporter gene transcription level.The material that 2 method 2 of embodiment is obtained sets liquid feeding nitrogen grind into powder in mortar, is added
The corresponding reagent of kit RNeasy kit (Tiangen) extracts total serum IgE.With iScript cDNA Synthesis kit
(TaKaRa) reverse transcription is cDNA, and quantitatively arrives 100ng μ l-1.With SYBR master mix (TaKaRa) kit, in ABI
QRT-PCR analysis is carried out using I fluorescent dye determination of SYBR green in 7500Real-time PCR system fluorescent quantitation instrument,
Using relative quantification 2-△△CtThe transcriptional level expression of method analysis gene.3 biology of experimental design repeat.
Use the EF1a (Genbank accession no.AF120093.1) of Ben Shi cigarette as the reference gene of tobacco,
Primer:
Upstream primer EF1a-QF: sequence is as shown in SEQ ID NO.1;
Downstream primer EF1a-QR: sequence is as shown in SEQ ID NO.2.
Detection GUS transcriptional level expresses the primer used:
Upstream primer mGUS-QF: sequence is as shown in SEQ ID NO.3;
Downstream primer mGUS-QR: sequence is as shown in SEQ ID NO.4.
The table of PMP1::GUS recombinant plasmid transient expression tobacco detection gus reporter gene transcriptional level is shown in Fig. 4-B
It reaches, the results showed that 2h of the artificial synthesized PMP1 promoter after phytophthora inoculation can drive gus reporter gene in transcriptional level
4.16 times of up-regulated expression.
With tobacco transient expression system, the active method of two different detection gus reporter genes is finally demonstrated artificial
The PMP1 promoter of synthesis can induce early stage fast driving reporter gene up-regulated expression downstream in phytophthora.It can be seen that PMP1
Promoter is phytophthora inducible promoter.Used primer is shown in Table 1 in this research.
Used fluorescent quantitation primer in 1, table research
The sequence of the artificial synthesized minimal promoter PMP1 of table 2
It is recognised that the illustrative embodiments that above-described embodiment uses only for illustrating inventive principle, however this hair
Bright to be not limited only to this, those skilled in the art can make various improvement and change in the case where not departing from real situation of the present invention, this
A little improvement and change also belong to protection scope of the present invention.