甘蓝型油菜LPAT4基因克隆及其生物信息学分析

Cloning and Bioinformatics Analysis of LPAT4 in Rapeseed

为进一步研究油菜LPAT4基因,通过检索与拟南芥LPAT4序列相似度较高的油菜EST序列,拼接后与白菜和甘蓝的LPAT4序列进行同源比对,设计一对引物,从甘蓝型油菜湘油15中扩增全长LPAT4 CDs序列。共获得2条CDs序列,它们的长度分别为1 143,1 140 bp,分别命名为BnLPAT4-1和BnLPAT4-2。BnLPAT4-1编码380个氨基酸,所得蛋白质的相对分子质量和等电点分别为43.29 kDa和8.74;BnLPAT4-2编码379个氨基酸,所得蛋白质的相对分子质量和等电点分别为43.16 kDa和8.93。他们均具有LPLAT_LCLAT1样结构域,同属于LPLAT超基因家族。比较所用油菜序列SNP分析显示,LPAT4共存在41个多态性位点,其中单变异位点7个,简约信息位点34个。这41个多态性位点中,引起同义变异的位点为23个,引起取代变异的位点18个,共导致16个氨基酸发生改变。分析表明,BnLPAT4-1和BnLPAT4-2为甘蓝型油菜湘油15号LPAT4基因的2个拷贝,从序列组成、理化性质、保守结构域以及同源建模4个方面来看,它们均具备LPLAT超基因家族的特征,为该基因家族的2个成员。

To further study on LPAT4 of Brassica napus,a pair of primers were designed to obtain the full length CDs sequence of rapeseed LPAT4 gene,according to the homologous comparison of B.campestris,B.oleracea and assembled EST sequence,which was strong similarity to the LPAT4 gene of Arabidopsis thaliana by searching bioinformatics at Geboc database.In this paper,two copies of full length CDs sequences（ 1 143,1 140 bp） have been cloned,these clones were designated as BnLPAT4-1 and BnLPAT4-2,respectively.BnLPAT4-1 encoded a protein of 380 amino acids with the molecular weights of 43.29 kDa and the isoelectric point of 8.74; BnLPAT4-2 encoded a polypeptide of 379 amino acids with the molecular weights of 43.16 kDa and the isoelectric point of 8.93.They belong to the LPLAT superfamily with LPLAT_LCLAT1 like domain.SNP analysis between different rapeseed cultivars revealed that LPAT4 exist 41 polymorphic sites,In which 7 were singleton polymorphic sites,and 34 were parsimony informative polymorphic sites.41 polymorphic sites leaded to 41 mutations,among them,23 were synonymous changes and 18 were replacement changes which contribute to 16 amino acids changed.In terms of sequence composition,physico-chemical property,conserved domain and homologous-modeling analysis,the analyses showed that BnLPAT4-1 and BnLPAT4-2 were two copies of Xiangyou 15 LPAT4 gene,at the same time,they should be the members of LPLAT superfamily.