Study On The Transcriptional Regulationmechanism Of Soybean Flowering Suppressorgene GmFT1a

Soybean(Glycine max(L.)Merr.)is a typical short-day dicotyledonous plant,and it is sensitive to the photoperiod.Soybean photoperiod molecular mechanism research focused on the flower-promoting genes and fewer represses flowering genes.In arabidopsis,FT is an integrator that converges the signals from several flowering pathways.So far,In soybean,at least 10 FT homologs have been identified.legumesspecific E1.GmFT1a has been confirmed to have represses flowering in soybean,but its transcriptional regulation mechanism is not clear.In this study,the promoter of GmFT1a was cloned and analyzed.Revealing the molecular mechanism of GmFT1a,providing a theoretical basis for the molecular mechanism of soybean photoperiod flowering.In this experiment,promoter of GmFT1a was cloned using ZGDD as material and analyzed by bioinformatics.its promoter fragments were fused with the GUS reporter gene transform into arabidopsis.The transgenic arabidopsis was histochemical stained and the Quantitative Real-time PCR detection of GUS expression sites and expression was performed.The expression vector was transferred into arabidopsis protoplasts to complete the double luciferase assay to determine the relationship between E1 and GmFT1a.The expression of GmFT1a in E1 RNAi plants was deter-mined under long/short days condition.The main results are as follows:1.The GmFT1a promoter with a length of 4971 bp was cloned using ZGDD as material.Bioinformatics analysis found that the fragment had 19 light-responsive elements that was concentrated in five areas.Compared with promoter of the reference genome,it was found that the fragment had 20 base insertions and deletions.2.The pGFP-GmFT1a pro-GUS vector was constructed and transformed into arabidopsis.For histochemical staining and Quantitative Real-time PCR in rosette leaves,roots,flowers and pods of arabidopsi.GUS staining found that the 4 parts can be stained.In addition to the root,the rest of the parts with the driver promoter increased,the scope and intensity of staining also increased;Quantitative Real-time PCR detection found that GUS was expressed in 4 parts,but the expression in the root was the lowest.The results indicates that the Gm FT1 a promoter drives GUS gene expression in all parts,with the exception of the root,the rest of the GUS gene expression will increase as the promoter fragment increases.3.To study the upstream genes of GmFT1a.The expression of GmFT1a of E1 RNAi plants was measured in long/short days.The results suggesting that the expression of GmFT1a was significantly lower than that of wild type,indicating that when E1 expression was suppressed,the expression of GmFT1a was also suppressed.4.Protoplasts of arabidopsis were prepared by enzymatic method.Multiple pGreenII-0800-GmFT1a pro-LUC vectors were constructed,and transformed with p16318-E1 vectors into protoplasts of arabidopsis,and fluorescence signals were detected.When the p16318-E1 vector is present,the fluorescence signal is significantly increased,which indicates that the promoter activity of GmFT1a is significantly increased when E1 is present.It is suggested that E1 may regulate its expression by binding to GmFT1a promoter.In summary,the results indicate that the genes driven by the GmFT1a promoter are expressed in all organs,and E1 may bind to the GmFT1a promoter and promote regulate the expression of GmFT1a.