木薯MeHB2转录因子的克隆与表达分析

Cloning and Expression of MeHB2 Transcription Factor in Cassava

该研究以木薯(Manihot esculenta Crantz)Ku50为实验材料,采用RT-PCR方法从叶片中克隆了1个HD-Zip基因MeHB2。MeHB2基因含有882bp的开放阅读框,编码293个氨基酸。蛋白质保守结构预测显示,MeHB2编码的蛋白含有Homeodomain、Leu zipper和HD-Zip_N等结构域,属于HD-Zip II成员。进化树分析表明,MeHB2与麻疯树、杨树和杞柳中同源基因的亲缘关系较近。实时荧光定量PCR分析表明,低温胁迫、渗透胁迫、ABA和H2O2均可诱导MeHB2基因的表达,而盐胁迫抑制其表达。此外,MeHB2的表达量还受到遮荫胁迫的诱导。研究表明,MeHB2在木薯非生物逆境调控中扮演重要角色。

Cassava cultivar ‘Ku50＇was used as experiment materials in this study.A HD-Zip gene,MeHB2,was cloned from leaves of cassava‘Ku50＇by RT-PCR method.This gene contained 882 bp open reading frame（ORF）encoding 293 amino acids.Protein conserved domain prediction showed that MeHB2 protein contained several domains such as Homeodomain,Leu zipper and HD-Zip_N,indicating this gene belonged to members of HD-Zip II.Phylogenetic analysis exhibited that MeHB2 had close genetic relationship with its homologous genes in Jatropha curcas,Populus trichocarpaand Salix purpurea.Quantitative real-time PCR analysis revealed that low temperature,osmotic,ABA and H2O2 treatments significantly induced the expression of MeHB2,but salt stress depressed its expression.In addition,the expression of MeHB2 was also induced by shade stress.The results indicated that MeHB2 plays important roles in abiotic stress regulation in cassava.