苦荞FtCBL基因的鉴定及对干旱与高钙胁迫的响应

Identification of FtCBL Genes in Fagopyrum tataricum and Their Stress Responses to Drought and High Calcium

植物CBL基因在逆境胁迫应答方面具有重要作用,鉴定苦荞FtCBL基因,并探索其对干旱高钙胁迫的响应具有重要意义。利用生物信息学方法鉴定FtCBL基因,通过模拟胁迫实验,研究FtCBL基因在干旱、高钙和干旱+高钙下的表达规律。共鉴定到5个苦荞FtCBL基因,均具有EF-hand钙结合结构域,分别定位于Ft3(2个)、Ft4(1个)和Ft5(2个)染色体上,cDNA长度在642-684 bp间,编码蛋白含213-227个氨基酸,序列高度保守。干旱下苦荞CAT与APX活性急剧升高,但在高钙下差异不显著,说明苦荞较适宜高钙环境生长。干旱下FtCBL1在8 h、24 h下调表达,FtCBL2上调表达,FtCBL3-1在8 h上调表达;高钙下FtCBL1在8 h、24 h和FtCBL9在24 h下调表达,FtCBL2上调表达;干旱+高钙下FtCBL3-1在8 h、24 h上调表达。共鉴定到5个FtCBL基因,其中FtCBL1、FtCBL2响应干旱、高钙胁迫,FtCBL3-1响应干旱、干旱+高钙胁迫,FtCBL9响应高钙胁迫。

Plant CBL genes play important roles in stress response.It is of great significance to identify FtCBL genes of tartary buckwheat(Fagopyrum tataricum L.)and to explore its responses to drought and high calcium stress.Bioinformatics methods were conducted to identify the FtCBL gene of tartary buckwheat.The expression of FtCBL gene under drought,high calcium and combined drought and high calcium treatment was investigated by mimicing stress.A total of 5 FtCBL genes with conserved EF-hand calcium-binding domain were identified,which were located at chromosome Ft3(2),Ft4(1)and Ft5(2).Their cDNA length was 642-684 bp,encoding 213-227 amino acids with highly conserved sequence.The CAT and APX enzyme activities of tartary buckwheat increased sharply under drought,but the difference was insignificant under high calcium,indicating that tartary buckwheat was relatively suitable for growing under high calcium environment.Under drought stress,FtCBL1 was down-regulated at 8 and 24 h,but FtCBL2 at 8 and 24 h and FtCBL3-1 at 8 h were up-regulated.Under high calcium stress,FtCBL1 at 8 and 24 h and FtCBL9 at 24 h were down-regulated,whereas FtCBL2 was up-regulated.Under combined drought and high calcium stress,FtCBL3-1 was up-regulated at 8 and 24 h.A total of 5 FtCBL genes are identified in tartary buckwheat.FtCBL1 and FtCBL2 are induced by drought stress and high calcium stress,respectively,FtCBL3-1 is induced by drought stress and combined drought and high calcium stress,and FtCBL9 is induced by high calcium stress.