CN101921784A

CN101921784A - Genes with functions of delta6 fatty acid desaturase and application thereof

Info

Publication number: CN101921784A
Application number: CN2010101676333A
Authority: CN
Inventors: 胡赞民; 宋丽英; 张岩; 胡军; 尹维波; 陈宇红
Original assignee: Institute of Genetics and Developmental Biology of CAS
Current assignee: Institute of Genetics and Developmental Biology of CAS
Priority date: 2007-07-25
Filing date: 2007-07-25
Publication date: 2010-12-22
Anticipated expiration: 2027-07-25
Also published as: CN101921784B

Abstract

The invention utilizes two genes RnD6C and RnD6D which root in DNA of Ribes nigrum L. and have complete reading frames and expresses the genes in a yeast expression system. GC-MS analysis shows that the protein coded by the two genes in the yeast can respectively catalyze applied substrates linoleic acid (LA) and alpha-linoleic acid (ALA) to respectively generate gamma-linoleic acid (GLA) and stearidonic acid (SDA). The genes have the functions of delta6 fatty acid desaturase. The genes can be applied to gene engineering technology to produce GLA and SDA by using a lower eukaryotic cell expression system and a plant expression system.

Description

Has Δ 6The gene of fatty acid dehydrogenase function and application thereof

The application is that application number is dividing an application of 2007101194771 patent application.

Technical field

The present invention relates to plant code gene and application thereof.Particularly, relate to two gene RnD6C and RnD6D with entire reading frame frame, it derives from the two segment DNA sequences of blackcurrant (Ribes nigrum L.) respectively, and two gene orders with entire reading frame frame of cloning based on this.The invention still further relates to this coded by said gene and have Δ ⁶The polypeptide of fatty acid dehydrogenase function, and contain eukaryotic expression vector and plant expression vector, the host cell such as low of this dna sequence dna and utilize this gene to transform the application of lower eukaryotes and plant production GLA and SDA respectively.

Background technology

(Polyunsaturated fatty acids PUFAs) is meant and contains two or more pairs key and carbon chain length is the straight chain fatty acid of 18～22 carbon atoms polyunsaturated fatty acid, mainly comprises linolic acid (linoleic acid, LA, 18:2 Δ ^9,12), gamma-linolenic acid (γ-linolenic acid, GLA, 18:3, Δ ^6,9,12), arachidonic acid (Arachidonic Acid, AA, 20:4 Δ ^5,8,11,14, timnodonic acid (Eicosapentaenoic Acid, EPA, 20:5 Δ ^5,8,11,14,17), docosahexenoic acid (Decosahexaenoic Acid, DHA, 20:5 Δ ^{4,7,10,11,16,19}) etc.Wherein, linolic acid and linolenic acid are acknowledged as essential fatty acid (Essential fatty acids, EFA), further derivation become to have the highly unsaturated fatty acids of difference in functionality, as AA, EPA, DHA etc.

PUFAs has very important physiological function.The first, PUFAs plays a significant role in physiological functions such as cardiovascular motion, brain, retina and neurological tissue development.The second, DHA and EPA have the good anticancer effect, as preventing the generation of (especially postmenopausal women) mammary cancer.The 3rd, polyunsaturated fatty acids such as arachidonic acid, EPA and DHA have been brought into play important effect in immunomodulatory.The 4th, polyunsaturated fatty acid can also have the skin aging of preventing, delay senility, promotes effects such as hair growth.

In the fatty acid metabolism process, Δ ⁶Fatty acid dehydrogenase (Δ ⁶-fatty acid desaturase, D6D) the 6th carbon atom dehydrogenation of catalytic substrate linolic acid (LA) and alpha-linolenic acid (ALA) forms gamma-linolenic acid (GLA) [1] and therapic acid (Stearidonic acid, SDA, 18:4 Δ respectively ^6,9,12,15).

Gamma-linolenic acid can further form AA, Prostaglandins and Leukotrienes class physiologically active substance by carbochain prolongation and dehydrogenation again, and these products produce material impact in a series of physiological functions such as brain development, vision, anaphylaxis and cardiovascular motion of people.A kind of essential unsaturated fatty acids as human body, gamma-linolenic acid has reducing blood-fat, anti peroxidation of lipid, fat-reducing, inhibition ulcer, strengthens a series of biological functions [1 such as Regular Insulin, antithrombotic cardiovascular disorder, 2], be studied utilization [3] as a kind of new VITAMIN-vitamin F in the world at present.SDA is the metabolic precursor thereof of EPA and DHA, is easy to be converted into EPA and DHA in human body, and utilising efficiency is 4 times of ALA, and effectively alleviation lacks relevant physiological maladies with EPA and DHA.Certainly also can obtain effect same by directly replenishing EPA or DHA.

Yet the existing commercial source of PUFAs mainly is specific spermatophyte, marine fishes and some animal tissues.Except LA, the market requirement of growing PUFAs all can not be satisfied in existing source aspect two of ultimate production and quality.This mainly is based on some following reasons:

(1) plant resources of PUFAs is subjected to season and region restriction, the instability of PUFAs output and quality; And plant resources mostly yields poorly, is not suitable for establishing in large scale.For example: the plant biomass such as root of Redsepal Eveningprimrose, Borrago officinalis and blackcurrant that contain gamma-linolenic acid are 300～600kg/ha only, well below the output [4] of the 3t/ha of conventional oil crops such as rape.

(2) limited natural marine fishing resources are because overfishing causes fishing resources to lack, and fish oil inherent fishy smell and oxidative instability, limited the further utilization of PUFAs;

(3) owing to need inferior oil is refined, increased the production cost of PUFAs greatly.Cause the high market value of pure product PUFAs thus, hindered its many potential purposes.

In view of the supply of PUFAs can not satisfy its demand very soon and be applied to the deficiency of the required pure product PUFAs supply of biologics, therefore be necessary the substitutability source of seeking to commercially produce.

So, as the key enzyme-Δ in GLA and the SDA production ⁶Fatty acid dehydrogenase is more and more studied and is utilized.Up to now, Δ ⁶Fatty acid dehydrogenase gene clone's acquisition from animal [5], plant [4], fungi [6] and nematode different biologies such as [7], and in yeast saccharomyces cerevisiae [7,8], tomato [9], tobacco [4,10], rape [6,8] and soybean [11], successfully obtained expression.

In plant, GLA and SDA exist only in a few plants such as root of Redsepal Eveningprimrose (Oenothera sp.), Borrago officinalis (Borago officinalis L.), blackcurrant [12], and the seed oil production of these plants also becomes the primary commercial source of present GLA in the world and SDA.Utilize the produce oil fungi fermentation also can extract and obtain GLA and SDA.But the GLA and the SDA output that obtain by existing these modes of production are all very low, can not satisfy the growing market requirement [13] far away.Therefore, utilize yeast saccharomyces cerevisiae or transgenosis oil plant crop plant to express the external source Δ ⁶GLA produced by fatty acid dehydrogenase and SDA has important Research Significance and economic worth.In addition, though Borrago officinalis [5] have Δ ⁶The existing abroad research report of fatty acid dehydrogenase gene, but two genes of the application are the Δs that derive from blackcurrant ⁶Fatty acid dehydrogenase gene does not at home and abroad appear in the newspapers so far.

Summary of the invention

The invention provides two gene RnD6C, RnD6D, its nucleotide acid sequence is respectively shown in SEQID NO:1 and SEQID NO:2, these two genes derive from the dna fragmentation of blackcurrant (Ribesnigrum L.) respectively, encoded polypeptide is respectively as SEQ ID NO:3, shown in the SEQ ID NO:4.

Another object of the present invention provides eukaryotic expression vector such as the Yeast expression carrier such as low that contains gene RnD6C, RnD6D, and utilizes this expression vector transformed yeast cells.Polypeptide expressed in transformed yeast cells has Δ ⁶Fatty acid dehydrogenase function, catalysis adds the substrate linolic acid and alpha-linolenic acid generates gamma-linolenic acid (GLA) and therapic acid (SDA) respectively respectively.

Because what this genoid was coded is an albumen, can adopt the yeast saccharomyces cerevisiae expression system to carry out vivoexpression, but because this albumen is membranin, even in the vivoexpression system, express, also more difficult separation and purification.So general the employing investigated expressed albumen the method for the catalytic activity that adds substrate carried out Function Identification.

In the yeast saccharomyces cerevisiae expression system that is adopted, recipient bacterium is uridylic defective type INV ScI, itself do not contain LA (linolic acid), ALA (alpha-linolenic acid), GLA (gamma-linolenic acid) and SDA, therefore, adding under the linoleic condition of substrate, if in Yeast engineering bacteria, detect catalysate GLA or SDA, just can determine that the coded albumen of foreign gene has obtained expression in the yeast saccharomyces cerevisiae expression system, produced katalysis to adding substrate.So yeast saccharomyces cerevisiae is as the most frequently used, the effectively expressing system of Δ 6, the functional evaluation of Δ 12-fatty acid dehydrogenase gene of research external source, and existing many successful researchs reports [4,6,7].The detection of lipid acid mainly adopts GC-MS (gas chromatography-mass spectrography technology) to finish.Its principle is by GC (gas-chromatography) different fatty acid components to be separated, and respectively every kind of component is carried out the mass spectrometry analysis by MS (mass spectrum) detector then, thus the coupling analytical technology of the comparative maturity of the composition of definite each component and content.

Another purpose of the present invention provides a kind of plant expression vector that contains gene RnD6C, RnD6D.Can use any expression vector that can guide foreign gene in plant, to express.These plant expression vectors include but not limited to, the double base agrobacterium vector, and for example pBIN19, pBI121, pB221, pCambia 1300, the plant expression vector of pGreen etc.

Carrier of the present invention also can contain suitable promotor.Can use any strong promoter in the present invention.These promotors include but not limited to cauliflower mosaic virus (CaMV 35S), Ubiqutin, Actin promotor.It can use separately or be used in combination with other plant promoter.

Expression vector of the present invention can be by the use Ti-plasmids, the Ri plasmid, and plant viral vector, directly DNA transforms, microinjection, modes such as electroporation import vegetable cell.

The low eucaryon host that waits that can use method of the present invention to transform is selected from the group of being made up of lower eukaryotes such as yeast, algae.

Can use method plant transformed host of the present invention to comprise plants such as tobacco, rape, Sunflower Receptacle, soybean, tomato, castor-oil plant, sesame and peanut.

The invention still further relates to gene RnD6C, the RnD6D application in producing GLA and SDA.

Description of drawings

Fig. 1 .RnD6C fragment nucleotide sequence, SEQ ID NO:1.

Fig. 2 .RnD6D fragment nucleotide sequence, SEQ ID NO:2.

Fig. 3. gene RnD6C encoded polypeptide sequence, SEQ ID NO:3, wherein line part is respectively Cytb5 functional domain and three His Box functional domains.

Fig. 4. gene RnD6D encoded polypeptide sequence, SEQ ID NO:4, wherein line part is respectively Cytb5 functional domain and three His Box functional domains.

Fig. 5. the Yeast expression carrier figure of gene RnD6C and RnD6D.

Fig. 6. the plant expression vector figure of gene RnD6C and RnD6D.A) with the plant expression vector figure of Totomycin (Hyg) as the RnD6C/D of selection markers; B) the plant expression vector figure of the RnD6C/D of removal selection markers.

Fig. 7. the total fatty acids GC-MS that gene RnD6C and RnD6D express in yeast saccharomyces cerevisiae is expressed analyzes

A) GC-MS of INV ScI yeast strain lipid acid composition;

B) GC-MS of LA (linolic acid), GLA (gamma-linolenic acid) standard model is formed and be added with to INV ScI yeast strain lipid acid;

C) contain unloaded pYES2 expression plasmid zymic total fatty acids GC-MS;

D) contain the total fatty acids GC-MS of unloaded pYES2 expression plasmid yeast after adding the LA substrate for induction;

E) the total fatty acids GC-MS of yeast after adding the LA substrate for induction of expression RnD6C gene, the red arrow indication is the product peak;

F) the total fatty acids GC-MS of yeast after adding the LA substrate for induction of expression RnD6D gene, the red arrow indication is the product peak;

G) contain the total fatty acids GC-MS of unloaded pYES2 expression plasmid yeast after adding the ALA substrate for induction;

H) the total fatty acids GC-MS of yeast after adding the ALA substrate for induction of expression RnD6C gene, the red arrow indication is the product peak;

I) the total fatty acids GC-MS of yeast after adding the ALA substrate for induction of expression RnD6D gene, the red arrow indication is the product peak;

J) started the total fatty acids GC-MS of the transgene rape H165 seed of RnD6D genetic expression by the napin promotor, the red arrow indication is the product peak;

K) the total fatty acids GC-MS of contrast-unconverted rape H165 seed.

Fig. 8. MS collection of illustrative plates during RnD6C, RnD6D genetic expression catalysate GC-MS analyze in the yeast saccharomyces cerevisiae, the MS figure of the yeast expression catalysate GLA of a:RnD6C, RnD6D; B: the MS figure of gamma-linolenic acid standard substance.

Embodiment

Describe the present invention in detail below with reference to embodiment and accompanying drawing.What those having ordinary skill in the art will appreciate that is, following embodiment is illustrational purpose, and it should not be interpreted as limitation of the present invention by any way.Protection scope of the present invention is limited by accompanying Claim.

The acquisition of embodiment one, RnD6C, RnD6D gene

1. the preparation of blackcurrant genomic dna

With blackcurrant (Ribes nigrum L.) the live body plant planted in the Beijing Botanical Garden is material, get its young leaflet tablet (about 100mg), in 7ml Ep pipe, add steel ball (diameter 5mm), place the freezing 20-30min of liquid nitrogen, high-speed breakage on the whirlpool device, repeatable operation 2-3 time, broken fully to material.The CTAB extract of adding 1-2ml preheating (referring to " fine works molecular biology experiment guide " 2001, Science Press, Yan Ziying, Wang Hailin is translated), mixing.65 ℃ of water-bath 30min.Add the equal-volume chloroform, the soft about 5min of extracting.In the centrifugal 10min of 12000rpm room temperature.Get supernatant, add 1/2 volume Virahol mixing, room temperature is placed 10min deposit D NA.With the Tip head DNA that is settled out is chosen, with washed twice in 70% ethanol, room temperature is placed 30min in 70% ethanol.Remove 70% ethanol, dry up in the air.Be dissolved in an amount of sterilization ddH ₂O ,-20 ℃ of preservations.

2.RnD6C, the clone of RnD6D dna fragmentation

The design primer is cloned RnD6C, RnD6D respectively from the DNA that extract the front dna fragmentation.Used reaction system is as follows:

PCR reaction system (50 μ l):

Cut glue behind the PCR product electrophoresis (1% sepharose concentration) and reclaim purpose fragment (RnD6C, RnD6D, about 1.3kb), be connected into pGEM-T carrier (available from Promega company), sequence verification.

The primer is as follows respectively:

1) clone's the primer of .RnD6C dna fragmentation

Forward primer

Kpn?I

5′-CGCG GGTACCATGGCTAATGCAATCAAG-3′(SEQ?ID?NO：5)

Reverse primer Sac I

5′-CGCC GAGCTCTCAGCCATAGGTGTTGAC-3′(SEQ?ID?NO：6)

2) clone's the primer of .RnD6D dna fragmentation

Forward primer Kpn I

5’-CGCG GGTACCATGGGTGAAAATGGAAGG-3’(SEQ?ID?NO：7)

Reverse primer Sac I

5’-CGCC GAGCTCTCAACCATAGGTGTTGAC-3’(SEQ?ID?NO：8)

The structure of embodiment two, RnD6C, RnD6D gene yeast carrier

From the pGEM-T carrier that contains gene RnD6C and RnD6D, utilize Kpn I, Sac I restriction enzyme site, two backs of cutting obtain RnD6C and RnD6D gene, directed cloning is in Yeast expression carrier pYES2 (available from Ivitrogen company), obtain expression plasmid of yeast pYRnD6C and pYRnD6D, transformed into escherichia coli DH-5 α (being preserved by this laboratory) preserves.Its carrier figure sees Fig. 5.

Embodiment three, RnD6C, the expression of RnD6D gene in yeast

1. zymic transforms

With reference to the described method of the pYES2 Kit of Invitrogen company (Cat# V285-20), expression plasmid of yeast pYRnD6C and pYRnD6D with above-mentioned mosaic gene, adopt Lithium Acetate mediated transformation yeast saccharomyces cerevisiae auxotrophic strain INV Sc I (purchasing company) in Invitrogen, with unloaded pYES2 plasmid is contrast, obtains to contain the yeast cell of each expression plasmid.

2. the abduction delivering of transformed yeast cell

Get the yeast list bacterium colony that contains the conversion of goal gene expression plasmid of yeast, be inoculated in 50ml SC-U nutrient solution (with reference to the described prescription of the pYES2 Kit of Invitrogen company) and contain in the SC-U nutrient solution of 2% silk floss sugar 250rpm, 28 ℃, overnight incubation; Add NP-40 (available from BBI company) (final concentration 1%), external source linolic acid and alpha-linolenic acid substrate (available from Sigma company) (final concentration is 0.003%), and yeast expression inductor D-semi-lactosi (available from Amresco company) (final concentration is 2%) 250rpm, cultivate the 48h abduction delivering for 22 ℃.

Embodiment four, RnD6C, RnD6D gene yeast representation are to Δ ⁶The GC-MS of fatty acid dehydrogenase substrate catalysate analyzes

1. the extraction of lipid acid and esterification.

Yeast thalline after centrifugal collection is got and induced, deionized water wash, 50 ℃ of oven dry.Get 40mg yeast powder (yeast of the acquisition of inducing through 50 ℃ of oven dry promptly in example 3.2) and fully grind, add 5ml 5%KOH-CH ₃OH adds HCl and is acidified to its pH value and reaches 2.0 behind 70 ℃ of water-bath 5h.Add 4ml14%BF again ₃-CH ₃OH (available from Aldtich company) solution, 70 ℃ of water-bath 1.5h.Add 2ml 0.9%NaCl solution, static a moment behind the mixing.Add the 2ml chloroform: normal hexane (V/V1: 4) extracting, draw extract, N ₂Dry up.Be dissolved in 100 μ l ethyl acetate at last.

2. end product GC-MS check and analysis experiment.

Used GC-/MS instrument is TurboMass (a PerkinElmer company), pillar: BPX-70,30m * 0.25mm * 0.25vm, 120 ℃ of column temperatures, 230 ℃ of vaporizer temperature.Get sample on the 1 μ l end product, splitting ratio 10: 1.

3.GC-MS interpretation of result.

Comparison diagram 7-1a, 7-1b and 7-1e, show and do not adding under the linolic acid substrate condition, used yeast engineering plant and contain in the unloaded pYES2 expression plasmid of inductive yeast and do not have new product peak to occur illustrates not contain in used yeast engineering strain and the unloaded pYES2 expression plasmid zymic total fatty acids to add substrate linolic acid (LA), alpha-linolenic acid (ALA) and catalysate gamma-linolenic acid (GLA), therapic acid (SDA).

When adding the linolic acid substrate, and when carrying out abduction delivering, contrast (unloaded pYES2) does not also have the appearance of product peak gamma-linolenic acid (GLA) (referring to Fig. 7-1d).And after the yeast expression bacterium of pYRnD6C/D induced, add substrate linolic acid (LA) and can be generated gamma-linolenic acid (GLA) (referring to Fig. 7-1e and 7-1f) by catalysis.

Comparison diagram 7-1d, 7-1e and 7-1f can find when retention time is the 7.25min left and right sides, have a new material to generate.Its appearance time and peak figure and the mass spectrum consistent (referring to Fig. 8 a and figure b) of mass spectrum with standard substance gamma-linolenic acid (available from Sigma company) are defined as gamma-linolenic acid.

When adding the alpha-linolenic acid substrate, and when carrying out abduction delivering, contrast (unloaded pYES2) does not also have the appearance of product peak SDA (referring to Fig. 7-2g).And after the yeast expression bacterium of pYRnD6C/D induced, add the substrate alpha-linolenic acid and can be generated SDA (referring to Fig. 7-2h and 7-2i) by catalysis.

Comparison diagram 7-2g, 7-2h and 7-2i can find when retention time is the 7.75min left and right sides, have a new material to generate.Be defined as SDA according to its appearance time and mass spectrum.

Above result's proof derives from two gene RnD6C, RnD6D successful expression in yeast saccharomyces cerevisiae of blackcurrant, and expressed albumen can distinguish catalytic substrate linolic acid (LA) and alpha-linolenic acid (ALA) generates gamma-linolenic acid and SDA.

The structure of embodiment five, RnD6C, RnD6D gene plant expression vector

1.napin the structure of promotor napin-T intermediate carrier

Extract the total DNA of (juncea) rape, (method is referring to embodiment 1.1).Clone's the primer of napin promoter fragment:

Forward primer: Hind III

5′-CGCG AAGCTTACTACAATGTCGGAGAGACAAGG-3′(SEQID?NO：9)

Reverse primer: BamH I

5′-CGCG GGATCCTTGTGTATGTTCTGTAGTGATGAGTTTTG-3′(SEQ?ID?NO：10)

With Pyrobest DNA Polymerase pcr amplification (reaction system is referring to embodiment 1.2), cut glue behind the PCR product electrophoresis (1% sepharose concentration) and reclaim purpose fragment (about 1.8kb), be connected into pGEM-T carrier (available from Promega company), sequence verification.

2.RnD6C, the structure of the RnFD6C/D-T intermediate carrier of RnD6D gene

Gene order according to RnFD6C/D, design contains the upstream and downstream special primer that restriction enzyme site is BamH I and Sac I respectively, with Pyrobest DNA Polymerase amplification purpose fragment RnFD6C and RnFD6D, reclaim purpose fragment directed cloning to the pGEM-T carrier, picking list bacterium colony, cut and sequence verification through PCR, enzyme, obtain the RnFD6C/D-T intermediate carrier.

3.RnD6C, the structure of the plant expression vector of RnD6D gene

1) structure of pC1300-napin

With Hind III and BamH I difference double digestion Napin-T and pCambia 1300, and recovery napin promoter fragment and pCambia 1300 carrier segments, connect transformed into escherichia coli, picking mono-clonal at random, through PCR, enzyme is cut checking and is obtained replacing the pC1300-napin plant expression vector that 35S promoter is the napin promotor.

2) structure of pC1300-nRnD6C/D plant expression vector

With BamH I and Sac I difference double digestion RnD6C/D-T and pC1300-napin, and reclaim RnD6C/D purpose fragment and pC1300-napin carrier segments, connect transformed into escherichia coli, picking mono-clonal at random, through PCR, enzyme is cut the plant expression vector that checking obtains pC1300-n RnD6C/D.Its carrier figure sees Fig. 6 a.

3) structure of the pC1300-nRnD6C/D of removal Totomycin (Hyg) selection markers

After building, with Xho I single endonuclease digestion, reclaim big segment then, after connection transformed, the picking mono-clonal carried out PCR at random, enzyme is cut the pC1300-nRnD6C/D plant expression vector that checking obtains to remove Totomycin (Hyg) selection markers.Its carrier figure sees Fig. 6 b.

Embodiment six, RnD6C, RnD6D gene and the conversion in plant

1. plant expression vector changes Agrobacterium over to

The single colony inoculation of picking Agrobacterium in 5ml YEP liquid nutrient medium, 28 ℃, 200rpm, shaken overnight is cultivated.The bacterium liquid of 2ml incubated overnight is added to contains in the 50ml YEP substratum, 28 ℃, 220rpm, shaking culture is to OD ₆₀₀Between 0.5-1.0.The centrifugal bacterium liquid of 5000rpm is abandoned supernatant, and precipitation is suspended in 10ml 0.5M NaCl, and 4 ℃, the centrifugal 5min of 5000rpm abandons supernatant, with the 20mM CaCl of 1ml precooling ₂Re-suspended cell.Get 0.2ml and add about 0.5-1 μ g plasmid DNA, mixing gently, liquid nitrogen flash freezer 1min, 37 ℃ of heat shock 5min, adding 1ml YEP solution, 28 ℃ of shaking culture 2-4h.The centrifugal bacterium liquid of 5000rpm is abandoned supernatant, and cell is resuspended in the 0.2ml YEP substratum, is uniformly coated on the YEP flat board that contains Kan, cultivates 48h for 28 ℃.Picking list bacterium colony carries out PCR and enzyme is cut checking at random.

2.Floral-dip method transforms rape (H165)

Select the swede type rape plant of initial bloom stage to handle, preceding 1d waters permeable in the field.Remove the top bud of main inflorescence and each branched inflorescence, remove open flower simultaneously, only keep soon open bud and be used for transforming.

The Agrobacterium that contains the target gene plant expression vector with 28 ℃ of incubated overnight of substratum of the fresh YEP+kan of 10ml is got the substratum that 5ml changes the fresh YEP+kan of 100ml over to, incubated overnight 22h again to 10:00 next day.The centrifugal Agrobacterium bacterium of 2500rpm liquid, abandon supernatant after, with 100ml transform Bufer (MS minimum medium+sucrose 5%+Silwet-77, pH5.8) resuspended to OD ₆₀₀=1.0 back dipping brassica napus inflorescences.1d is continuous at interval in the 10d handles 5 times.Put paper bag after having flooded.Remove paper bag behind the dip treating 24h until the results seed.

Embodiment seven, T1 are for the screening of seed

To the rape T1 that obtains after the dip treating for seed through 75% alcohol surface sterilization 30s, 0.1%HgCl ₂Sterilization 10min, be layered on the good in advance screening culture medium, through 7～15d screening and culturing, the green seedling of normal growth is carried out resistance screening (7～15d) the 2nd time, resistant plant after the 2nd screening is carried out resistance screening (7～15d) the 3rd time, the 2nd time, the 3rd time screening culture medium is: Ms+Kan (150mg/L).Change the green seedling after the screening for the third time over to flowerpot, hot-house culture to seed is gathered in the crops.

Directly be seeded in the field for the T1 that handles the back acquisition with the Agrobacterium that contains the pC1300-n RnD6C/D that removes selection markers for Semen Brassicae campestris, extract leaf DNA, by PCR screening positive plant.

Embodiment eight, RnD6C, RnD6D gene plant representation are to Δ ⁶The GC-MS of fatty acid dehydrogenase substrate catalysate analyzes

1. the extraction of lipid acid and esterification.

Get ripe contrast of 50-100mg or transgene rape seed, fully grind in the liquid nitrogen, add 5ml 5%KOH-CH ₃OH adds HCl and is acidified to its pH value and reaches 2.0 behind 70 ℃ of water-bath 5h.Add 4ml 14%BF again ₃-CH ₃OH (available from Aldrich company) solution, 70 ℃ of water-bath 1.5h.Add 2ml 0.9%NaCl solution, static a moment behind the mixing.Add the 2ml chloroform: normal hexane (V/V 1: 4) extracting, draw extract, N ₂Dry up.Be dissolved in 100 μ l ethyl acetate at last.

2. end product GC-MS check and analysis experiment.

Used GC/MS instrument is TurboMass (a PerkinElmer company), pillar: BPX-70,30m * 0.25mm * 0.25vm, 120 ℃ of column temperatures, 230 ℃ of vaporizer temperature.Get sample on the 1 μ l end product, splitting ratio 10: 1.

3.GC-MS interpretation of result.

Comparison diagram 7-2j and 7-2k compare with the Semen Brassicae campestris contrast that transforms, and two new product peaks appear in the transformant rape, compare with standard substance and yeast GC-MS result, can find when retention time is the 7.25min left and right sides, the product peak of GLA occurs; When retention time was the 7.75min left and right sides, the product peak of SDA appearred.Above result's proof derives from gene RnD6D successful expression in Semen Brassicae campestris of blackcurrant, and expressed albumen can distinguish catalytic substrate linolic acid (LA) and alpha-linolenic acid (ALA) generates GLA and SDA.This also just shows, changes RnD6C/D over to rape, can produce GLA and SDA as bio-reactor with transgene rape.

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7.Napier?JA，Hey?SJ，Lacey?DJ?and?Shewry?PR(1998)Identification?of?aCaenorhabditis?elegans?Δ ⁶-fatty-acid-desaturse?by?heterologousexpression?in?Saccharomyces?cerevisiae.Biochem?J?330：611-614.

8.Qiu?X，Hong?HP，Datla?N，MacKenzie?SL，Tayler?CD?and?Thomas?LT(2002)Expression?of?borageΔ ⁶-desaturase?in?Saccharomyces?cerevisiaeand?oilseed?crops.Can?J?Bot?80：42-49.

9.Cook?D，Grierson?D，Jones?C，Wallace?A，West?G?and?Tucker?G(2002)Modification?of?fatty?acid?composition?in?tomato(Lycopersicon?esculentum)by?expression?of?a?borageΔ ⁶-desaturase.Mol?Biotechnol.21(2)：123-128.

10.Sayanova?O，Smith?MA，Lapinskas?P，Stobart?AK，Dobson?G，ChristieWW，Shewry?PR?and?Napier?JA(1997)Expression?of?a?borage?desaturasecDNA?containing?an?N-terminal?cytochrome?b5?domain?results?in?the?accumulation?of?high?levels?ofΔ ⁶-desaturated?fatty?acids?in?transgenictobacco.Proc?Natl?Acad?Sci?USA?94：4211-4216.

11.Sato?S，Xing?AQ，Ye?XG，Schweiger?B，Kinney?A，Graef?G?and?Clemente?T(2004)Production?ofγ-Linolenic?Acid?and?Stearidonic?Acid?in?Seeds?ofMarker-Free?Transgenic?Soybean.Crop?Sci?44：646-652.

12.Ucciani?E(1995)Nouveau?Dictionnaire?des?Huiles?Végétales-Composition?en?Acides?Gras.Lavoisier，Paris?pp?3-596.

13.Gyves?EM，Sparks?CA，Sayanova?O，Lazzeri?P，Napier?JA?and?Jones?HD(2004)Genetic?manipulation?ofγ-linolenic?acid(GLA)synthesis?in?acommercial?variety?of?evening?primrose(Oenothera?sp.)Plant?Biotech2(4)：351-357.

Sequence table

＜110〉Inst. of Genetics and Development Biology, CAS

＜120〉have the gene and the application thereof of Δ 6 fatty acid dehydrogenase functions

<130>1

<160>8

<170>PatentIn?version?3.1

<210>1

<211>1347

<212>DNA

<213>Ribes?nigrum?L.

<400>1

atggctaatg?caatcaagaa?gtacatgaca?gttgaggagc?taaaagtgca?taacaagcca 60

gaggatttgt?ggatctctat?tcagggtaag?gtttacaatg?tcactgattg?gaaaaaggaa 120

cacccaggtg?gggatagctc?tctcctgaat?ctaggtggtc?aagatgtcac?agatgcattc 180

attgcttatc?atccaggtac?tgcttggcaa?tatcttgaca?ggttctttac?tgggtattat 240

ctcaaagatt?tcaatgtctc?agatgtatcc?aaagattata?gaaaacttgc?atctgagttt 300

accaaaatgg?gtctttttgc?aaagaaaggg?catggtgttt?tctactcctt?ttgtcttggg 360

gcattcttgt?ttgctgtttg?tgtttatggt?gttttgtatt?ctcaaagttt?gtttgtgcat 420

ttgtgttgtg?gtgggatttt?ggggttttta?tggatgcaaa?gtggttatgc?tggtcacgat 480

tctgggcatt?atcagacaat?gtctactcct?ttttatacca?atttggctca?aattcttact 540

ggaaattgcc?ttagtggtat?tagtatggct?tggtggaaat?ggacccacaa?tgctcaccac 600

gttgctgtta?atagtattga?ccatgaccct?gatcttcagt?acatgccatt?ttttgtcctc 660

tctcccaaat?tgttcaatgg?cataacttct?cgcttttatg?ggaggaagtt?ggagtttgat 720

gcttttgcta?ggttcatggt?aagttatcag?cattggacat?tttatccggt?gatgattttt 780

gcacgatttt?atatgtttgt?gcccacgttt?tttatgttgc?tttcaaagaa?aaaagtaccc 840

aacagacctt?tgaatatagc?gggaattatt?gtgttctgga?tttggtttcc?tcttcttgtt 900

tcatgccttc?ccaattggac?tgagaggatg?atgtttgtgc?tagtgagctt?tacagttact 960

tcaattcaac?acgttacatt?ttgtttgaat?cactactcgg?ctgataatta?tatgggacat 1020

cctactggga?acgattggtt?tgagaagcag?acaagtggga?ctttggacat?ttcgtgcccg 1080

tcttggatgg?attggtttca?tggtgggctg?caattccaaa?ttgagcatca?tttgttccca 1140

agattgcctc?gatgccagct?taggaaggtc?tctccttttg?tgaaagagct?ttgcaagaaa 1200

cacaatttgc?cttataggag?tttatcattt?tttgaggcca?atgttgcaat?cattaagacg 1260

ttgaggactg?ccgccttgca?agctcgcgac?ctatccaacc?ctatttcaaa?gaatttgcta 1320

tgggaagctg?tcaacaccta?tggctga 1347

<210>2

<211>1347

<212>DNA

<213>Ribes?nigrum?L.

<400>2

atgggtgaaa?atggaaggaa?gtacatgaca?gttgaggagc?taaaagtgca?taataagcca 60

gaggatttgt?ggatctctat?tcagggtaag?gtttacaatg?tcactgattg?gaaaaaggaa 120

cacccaggtg?gggatagctc?actcctgaat?ctgggtggtc?aagatgtcac?agatgcattc 180

attgcttatc?atccaggtac?tgtttggcaa?tatcttgaca?ggttctttac?tgggtattat 240

ctcaaagatt?tcaaagtctc?agatgtatcc?aaagattaca?gaaaacttgc?atctgagttt 300

accaaaatgg?gtctttttgc?aaagaaaggg?catggtgttt?tctactcctt?ttgtcttggg 360

gcattcttgt?ttgctgtttg?tgtttatggt?gttttgtatt?ctcaaagttt?gtttgtgcat 420

ttatgttgtg?gtgggatttt?ggggttttta?tggatgcaaa?gtggttatgc?tggtcatgat 480

tctgggcatt?accagacaat?gtctactcct?ttttatacca?atttggctca?aattcttact 540

ggaaattgcc?ttagtggtat?tagtatggct?tggtggaaat?ggacccacaa?tgctcaccac 600

attgctgtta?atagtattga?ccatgaccct?gatcttcagt?acatgccatt?ttttgttctc 660

tctcccaaat?tgttcaatag?cataacttct?cgcttttatg?ggaggaagtt?ggagtttgat 720

gcttttgcta?ggttcatggt?gagttatcag?cattggacat?tttatccggt?gatgattttt 780

gcacgatttt?atatgtttgt?gcctacgttt?tttttgttgc?tttcaaagaa?aaaagtaccc 840

aacagacttt?tgaatatagc?tggaattatt?gtgttctgga?tttggtttcc?tcttcttgtt 900

tcatgcctac?ccaattggac?tgagaggatg?atgtttgtgc?tagtgagctt?tacggttact 960

tcaattcaac?acgttacatt?ttgtttgaat?cactactcgg?ctgataatta?tatgggacat 1020

cctactggga?acgattggtt?tgaaaagcag?acaagtggga?ctttggacat?ttcgtgcccg 1080

tcttggatgg?attggtttca?tggtgggctg?caattccaac?ttgagcatca?tttgttccct 1140

cgaatgcctc?gatgtcagct?taggaaggtc?tctccttttg?tgaaggaact?ttgccagaag 1200

cataatttgc?cttataggag?tttgtcattt?ttcgaggcca?atgtcgcgac?cattaagacg 1260

ttgaggactg?cagccttgca?agctcgtgac?ctgtccaacc?ctattacaaa?gaatttgcta 1320

tgggaagctg tcaacaccta tggttga 1347

<210>3

<211>448

<212>PRT

<213>Ribes?nigrum?L.

<400>3

Met?Ala?Asn?Ala?Ile?Lys?Lys?Tyr?Met?Thr?Val?Glu?Glu?Leu?Lys?Val

1 5 10 15

His?Asn?Lys?Pro?Glu?Asp?Leu?Trp?Ile?Ser?Ile?Gln?Gly?Lys?Val?Tyr

20 25 30

Asn?Val?Thr?Asp?Trp?Lys?Lys?Glu?His?Pro?Gly?Gly?Asp?Ser?Ser?Leu

35 40 45

Leu?Asn?Leu?Gly?Gly?Gln?Asp?Val?Thr?Asp?Ala?Phe?Ile?Ala?Tyr?His

50 55 60

Pro?Gly?Thr?Ala?Trp?Gln?Tyr?Leu?Asp?Arg?Phe?Phe?Thr?Gly?Tyr?Tyr

65 70 75 80

Leu?Lys?Asp?Phe?Asn?Val?Ser?Asp?Val?Ser?Lys?Asp?Tyr?Arg?Lys?Leu

85 90 95

Ala?Ser?Glu?Phe?Thr?Lys?Met?Gly?Leu?Phe?Ala?Lys?Lys?Gly?His?Gly

100 105 110

Val?Phe?Tyr?Ser?Phe?Cys?Leu?Gly?Ala?Phe?Leu?Phe?Ala?Val?Cys?Val

115 120 125

Tyr?Gly?Val?Leu?Tyr?Ser?Gln?Ser?Leu?Phe?Val?His?Leu?Cys?Cys?Gly

130 135 140

Gly?Ile?Leu?Gly?Phe?Leu?Trp?Met?Gln?Ser?Gly?Tyr?Ala?Gly?His?Asp

145 150 155 160

Ser?Gly?His?Tyr?Gln?Thr?Met?Ser?Thr?Pro?Phe?Tyr?Thr?Asn?Leu?Ala

165 170 175

Gln?Ile?Leu?Thr?Gly?Asn?Cys?Leu?Ser?Gly?Ile?Ser?Met?Ala?Trp?Trp

180 185 190

Lys?Trp?Thr?His?Asn?Ala?His?His?Val?Ala?Val?Asn?Ser?Ile?Asp?His

195 200 205

Asp?Pro?Asp?Leu?Gln?Tyr?Met?Pro?Phe?Phe?Val?Leu?Ser?Pro?Lys?Leu

210 215 220

Phe?Asn?Gly?Ile?Thr?Ser?Arg?Phe?Tyr?Gly?Arg?Lys?Leu?Glu?Phe?Asp

225 230 235 240

Ala?Phe?Ala?Arg?Phe?Met?Val?Ser?Tyr?Gln?His?Trp?Thr?Phe?Tyr?Pro

245 250 255

Val?Met?Ile?Phe?Ala?Arg?Phe?Tyr?Met?Phe?Val?Pro?Thr?Phe?Phe?Met

260 265 270

Leu?Leu?Ser?Lys?Lys?Lys?Val?Pro?Asn?Arg?Pro?Leu?Asn?Ile?Ala?Gly

275 280 285

Ile?Ile?Val?Phe?Trp?Ile?Trp?Phe?Pro?Leu?Leu?Val?Ser?Cys?Leu?Pro

290 295 300

Asn?Trp?Thr?Glu?Arg?Met?Met?Phe?Val?Leu?Val?Ser?Phe?Thr?Val?Thr

305 310 315 320

Ser?Ile?Gln?His?Val?Thr?Phe?Cys?Leu?Asn?His?Tyr?Ser?Ala?Asp?Asn

325 330 335

Tyr?Met?Gly?His?Pro?Thr?Gly?Asn?Asp?Trp?Phe?Glu?Lys?Gln?Thr?Ser

340 345 350

Gly?Thr?Leu?Asp?Ile?Ser?Cys?Pro?Ser?Trp?Met?Asp?Trp?Phe?His?Gly

355 360 365

Gly?Leu?Gln?Phe?Gln?Ile?Glu?His?His?Leu?Phe?Pro?Arg?Leu?Pro?Arg

370 375 380

Cys?Gln?Leu?Arg?Lys?Val?Ser?Pro?Phe?Val?Lys?Glu?Leu?Cys?Lys?Lys

385 390 395 400

His?Asn?Leu?Pro?Tyr?Arg?Ser?Leu?Ser?Phe?Phe?Glu?Ala?Asn?Val?Ala

405 410 415

Ile?Ile?Lys?Thr?Leu?Arg?Thr?Ala?Ala?Leu?Gln?Ala?Arg?Asp?Leu?Ser

420 425 430

Asn?Pro?Ile?Ser?Lys?Asn?Leu?Leu?Trp?Glu?Ala?Val?Asn?Thr?Tyr?Gly

435 440 445

<210>4

<211>448

<212>PRT

<213>Ribes?nigrum?L.

<400>4

Met?Gly?Glu?Asn?Gly?Arg?Lys?Tyr?Met?Thr?Val?Glu?Glu?Leu?Lys?Val

1 5 10 15

His?Asn?Lys?Pro?Glu?Asp?Leu?Trp?Ile?Ser?Ile?Gln?Gly?Lys?Val?Tyr

20 25 30

Asn?Val?Thr?Asp?Trp?Lys?Lys?Glu?His?Pro?Gly?Gly?Asp?Ser?Ser?Leu

35 40 45

Leu?Asn?Leu?Gly?Gly?Gln?Asp?Val?Thr?Asp?Ala?Phe?Ile?Ala?Tyr?His

50 55 60

Pro?Gly?Thr?Val?Trp?Gln?Tyr?Leu?Asp?Arg?Phe?Phe?Thr?Gly?Tyr?Tyr

65 70 75 80

Leu?Lys?Asp?Phe?Lys?Val?Ser?Asp?Val?Ser?Lys?Asp?Tyr?Arg?Lys?Leu

85 90 95

Ala?Ser?Glu?Phe?Thr?Lys?Met?Gly?Leu?Phe?Ala?Lys?Lys?Gly?His?Gly

100 105 110

Val?Phe?Tyr?Ser?Phe?Cys?Leu?Gly?Ala?Phe?Leu?Phe?Ala?Val?Cys?Val

115 120 125

Tyr?Gly?Val?Leu?Tyr?Ser?Gln?Ser?Leu?Phe?Val?His?Leu?Cys?Cys?Gly

130 135 140

Gly?Ile?Leu?Gly?Phe?Leu?Trp?Met?Gln?Ser?Gly?Tyr?Ala?Gly?His?Asp

145 150 155 160

Ser?Gly?His?Tyr?Gln?Thr?Met?Ser?Thr?Pro?Phe?Tyr?Thr?Asn?Leu?Ala

165 170 175

Gln?Ile?Leu?Thr?Gly?Asn?Cys?Leu?Ser?Gly?Ile?Ser?Met?Ala?Trp?Trp

180 185 190

Lys?Trp?Thr?His?Asn?Ala?His?His?Ile?Ala?Val?Asn?Ser?Ile?Asp?His

195 200 205

Asp?Pro?Asp?Leu?Gln?Tyr?Met?Pro?Phe?Phe?Val?Leu?Ser?Pro?Lys?Leu

210 215 220

Phe?Asn?Ser?Ile?Thr?Ser?Arg?Phe?Tyr?Gly?Arg?Lys?Leu?Glu?Phe?Asp

225 230 235 240

Ala?Phe?Ala?Arg?Phe?Met?Val?Ser?Tyr?Gln?His?Trp?Thr?Phe?Tyr?Pro

245 250 255

Val?Met?Ile?Phe?Ala?Arg?Phe?Tyr?Met?Phe?Val?Pro?Thr?Phe?Phe?Leu

260 265 270

Leu?Leu?Ser?Lys?Lys?Lys?Val?Pro?Asn?Arg?Leu?Leu?Asn?Ile?Ala?Gly

275 280 285

Ile?Ile?Val?Phe?Trp?Ile?Trp?Phe?Pro?Leu?Leu?Val?Ser?Cys?Leu?Pro

290 295 300

Asn?Trp?Thr?Glu?Arg?Met?Met?Phe?Val?Leu?Val?Ser?Phe?Thr?Val?Thr

305 310 315 320

Ser?Ile?Gln?His?Val?Thr?Phe?Cys?Leu?Asn?His?Tyr?Ser?Ala?Asp?Asn

325 330 335

Tyr?Met?Gly?His?Pro?Thr?Gly?Asn?Asp?Trp?Phe?Glu?Lys?Gln?Thr?Ser

340 345 350

Gly?Thr?Leu?Asp?Ile?Ser?Cys?Pro?Ser?Trp?Met?Asp?Trp?Phe?His?Gly

355 360 365

Gly?Leu?Gln?Phe?Gln?Leu?Glu?His?His?Leu?Phe?Pro?Arg?Met?Pro?Arg

370 375 380

Cys?Gln?Leu?Arg?Lys?Val?Ser?Pro?Phe?Val?Lys?Glu?Leu?Cys?Gln?Lys

385 390 395 400

Sequence table

His?Asn?Lcu?Pro?Tyr?Arg?Ser?Leu?Ser?Phe?Phe?Glu?Ala?Asn?Val?Ala

405 410 415

Thr?Ile?Lys?Thr?Leu?Arg?Thr?Ala?Ala?Leu?Gln?Ala?Arg?Asp?Leu?Ser

420 425 430

Asn?Pro?Ile?Thr?Lys?Asn?Leu?Leu?Trp?Glu?Ala?Val?Asn?Thr?Tyr?Gly

435 440 445

<210>5

<211>28

<212>DNA

＜213〉artificial sequence

<400>5

cgcgggtacc?atggctaatg?caatcaag 28

<210>6

<211>28

<212>DNA

＜213〉artificial sequence

<400>6

cgccgagct?c?tcagccatag?gtgttgac 28

<210>7

<211>28

<212>DNA

＜213〉artificial sequence

<400>7

cgcgggtacc?atgggtgaaa?atggaagg 28

<210>8

<211>28

<212>DNA

＜213〉artificial sequence

<400>8

cgccgagctc?tcaaccatag?gtgttgac 28

<210>9

<211>33

<212>DNA

＜213〉artificial sequence

<400>9

cgcgaagctt?actacaatgt?cggagagaca?agg 33

<210>10

<211>39

<212>DNA

＜213〉artificial sequence

<400>10

cgcgggatcc?ttgtgtatgt?tctgtagtga?tgagtttg 39

Claims

1. gene RnD6C, its nucleotide sequence is shown in SEQ ID NO:1.

2. the gene RnD6C encoded polypeptide of claim 1, its aminoacid sequence is shown in SEQ ID NO:3.

3. an expression vector is characterized in that comprising the described gene of claim 1.

4. the expression vector of claim 3, it is low eukaryotic expression vector or the plant expression vector of waiting.

5. the expression vector of claim 4, wherein low to wait eukaryotic expression vector be pYES2.

6. the expression vector of claim 4, wherein said plant expression vector is the plant expression vector that is selected from pBIN19, pBI121, pB221, pCambia 1300 and pGreen.

7. the expression vector of claim 3, it is characterized in that also comprising promotor, described promotor is selected from cauliflower mosaic virus CaMV35S, Ubiqutin, Actin or plant tissue position specific expression promoter, and described promotor is used in combination separately or with other plant promoter.

8. host cell is characterized in that comprising the expression vector of claim 3.

9. the host cell of claim 8, wherein said expression vector are that the mode by Ti-plasmids, Ri plasmid, plant virus-based expression vector, directly DNA conversion, microinjection or electroporation imports.

10. the host cell of claim 8, it is low eukaryotic cell or the vegetable cell of waiting.

11. the host cell of claim 10, wherein said low eukaryotic cell such as grade is the cell of yeast, algae, and described vegetable cell comprises the cell of tobacco, rape, Sunflower Receptacle, soybean, tomato, castor-oil plant, sesame and peanut.

12. the application of the gene RnD6C of claim 1 in producing GLA and SDA.