小麦TaCYP78A5基因的克隆及生物信息学分析

Cloning and Bioinformatics Analysis of TaCYP78A5 Gene in Wheat

细胞色素P450(Cytochromes P450)蛋白家族含有硫羟基和血红素结构域,参与多种生物合成,CYP78A家族成员对籽粒大小形成有重要的功能。利用同源克隆的方法,分别从小麦大粒品系‘P271’和小粒材料‘中国春’中扩增到位于2AS、2BS、2DS上的TaCYP78A5-2A、TaCYP78A5-2B和TaCYP78A5-2D基因,编码534、544、549个氨基酸。通过分析发现在‘P271’和‘中国春’克隆到的TaCYP78A5序列一致,说明TaCYP78A5基因在这2个粒型的小麦中是保守的。CYP78A家族在水稻和拟南芥中具有非自主性细胞表达模式,结合对CYP78A家族的生物进化关系研究发现,CYP78A家族的各个基因在单子叶植物中是保守的。‘P271’和‘中国春’籽粒大小的差异,可能是TaCYP78A5基因在‘P271’中的基因表达量高于‘中国春’,引起种子发育过程中内表皮细胞的增殖,从而促进种子表皮增大,使得‘P271’种子大小和质量增加。

Cytochrome P450（Cytochromes P450）family contains sulfhydryl group,and heme structure domains have been proved to participate in a variety of biosynthesis.CYP78 Afamily members were found to play an important role in controlling grain size.In this study,TaCYP78A5-2 A,TaCYP78A5-2 Band TaCYP78A5-2 D genes which had encoding 534,544,549 amino acids respectively,were cloned from wheat of large grain line ‘P271’ and small grain material‘Chinese Spring＇and located on 2 AS,2 BS and 2 DS.There was no variation of TaCYP78A5 genes between ‘P271’ and ‘Chinese Spring＇,so this indicated that TaCYP78A5 gene was conserved in the two different grain sizes of wheat varieties.CYP78 Afamily was found as non-cell autonomous manner in rice and Arabidopsis thaliana seed development.Combined with the biological evolution of the CYP78 Afamily,we found that the CYP78 Afamilies of genes were conserved among monocotyledons.The difference of grain size between‘ P271’ and ‘Chinese Spring＇wheat is higher than that in ‘Chinese Spring＇due to the gene expression level of TaCYP78A5 in ‘P271’,and it caused the proliferation of inner epidermal cells during seed development,thereby the increasing seed epidermis could increase the size and mass of the ‘P271’ seeds.