苦荞转录因子基因FtbHLH4的克隆及其对非生物胁迫的应答

Cloning and Expression of FtbHLH4 in Fagopyrum tataricum and Response to Abiotic Stresses

根据苦荞花期转录组数据,克隆得到1个苦荞bHLH类转录因子基因,命名为FtbHLH4。采用实时荧光定量PCR技术,分析了非生物胁迫对苦荞芽期FtbHLH4基因表达的影响。序列分析表明,苦荞FtbHLH4基因DNA全长1 852bp,由7个外显子和6个内含子构成,符合GT-AG剪接原则;cDNA序列包含1个1 062bp的开放阅读框,编码353个氨基酸,具有bHLH类蛋白典型的螺旋-环-螺旋保守结构域。在脱落酸(ABA)、NaCl和PEG模拟干旱胁迫下,苦荞芽期FtbHLH4基因表达量均持续上升,至48h时达最大,分别为胁迫前的11.3倍、12.0倍和6.1倍。而在冷胁迫和UV-B胁迫下,苦荞芽期FtbHLH4基因表达量迅速下降,分别于6h和12h降低至胁迫前的24%和23%。研究推测FtbHLH4基因以不同机制参与了苦荞对非生物胁迫的应答过程。

According to transcriptome data of Fagopyrum tataricum at flowering stage,we cloned a bHLH transcription factor gene and designated as FtbHLH4.The expression patterns of FtbHLH4 under abiotic stresses were determined by qPCR.The results showed that the DNA sequence of FtbHLH4 was 1 852 bp in length and contained 7exons and 6introns,and in line with the principle of GT-AG splicing principle.The cDNA of FtbHLH4 contains a 1 062 bp ORF,which encoded 353 amino acids residues,and a conserved Helix-Loop-Helix domain.The expression of FtbHLH4 was up-regulated under ABA,NaCl and PEG stresses.After being treated with ABA,NaCl or PEG for 48 h,the expression level of FtbHLH4 increased to the maximum,which was 11.3,12.0and 6.1folds of the control,respectively.However,the expression of FtbHLH4 was down-regulated under cold and UV-B stresses.The expression level decreased to 24%and 23% of the control after 6hand 12 hstress treatments,respectively.These results suggested that FtbHLH4 participate in the response process of F.tataricum under the abiotic stresses in different mechanisms.