Molecular Cloning And Functional Analysis Of BnWRIs Transcription Factor Family In The Synthesis Of Fatty Acid In Brassica Napus

WRI1(WRINKLED1)is one of the key transcription factors in the regulation of lipid metabolism,which plays an important role in the process of carbon flow from sugar to oil and cell in the regulation of carbon and nitrogen balance.The regulation of WRI1 directly influences the synthesis and accumulation of lipids.Brassica napus L.is one of the most important oil crops,and the oil content is the key point of rapeseed breeding.Therefore,it is great significance to analysis the molecular mechanism of oil by study the function of WRI gene in rapeseed.In this study,it was found that there are 12 WR1 members in Brassica napus by bioinformatics analysis,and named Bn WR101-12.Cloned 10 CDSs(Bn WRI01,BnWRI02,Bn WRI03,BnWRI04,Bn WRI05,Bn WR106,Bn WR108,BnWRI10,BnWRI11,BnWRI12),and built entry vectors,plant transformation vectors and yeast transformation vectors through the Gateway system.By means of cluster analysis,BnWRI01,02 and 03 belong to the AtWRI1 subfamily,BnWRI04,05,06,and 08 belong to the AtWRI2 subfamily,BnWRI10 belongs to the AtWRI3 subfamily,BnWRI11 and 12 belong to the AtWRI4 subfamily.Evaluated the expression stability of 30 candidate genes by RT-qPCR,four stable expression of those candidate genes were selected as reference genes to analyze the expression characteristics of 10 Bn WRI.The relative expression of BnWRI01,03,04 and 06 are high in seed or pod.The relative expression of BnWRI10,11 and 12 are high in bud and early stage of inflorescence.It is indicating that BnWRI may regulated wih the synthesis of fatty acid in different tissues.The relative expression of 10 BnWRI transcription factors in low oil and late maturing type were higher than that in high oil and prematurity type at the same stage of the pod.The members of 10 BnWRI family transcription factors were located in nucleus by analysis of subcellular localization in protoplast.The effects of 10 Bn WRI on varieties of fatty acid composition in saccharomyces cerevisiae were different.There were no significantly effect on content of different fatty acids by the over expression of BnWRI01 in the INVSc1 yeast.It is reduced some fatty acids content significantly by the over expression of BnWRI02 and Bn WRI03 in the INVSc1 yeast.It is increased the fatty acid content significantly by the over expression of the remaining 7 Bn WRI in the INVSc1 yeast.This study confirms that Bn WRI03 transcription factor can interact with BnBCCP12 promoter to regulate the expression of BnBCCP1-2.