紫苜蓿盐诱导NAC转录因子的鉴定、克隆及表达分析

Identification, cloning and expression analysis of salt-induced NAC transcription factors in alfalfa

转录因子在植物逆境胁迫应答中发挥关键调控作用。NAC (NAM/ATAF1/2/CUC2)转录因子的耐盐功能已在多个物种中证实,但在紫苜蓿(Medicago sativa)中还鲜有报道。本研究通过对紫苜蓿进行转录组测序分析,发掘了10个盐诱导表达NAC转录因子并克隆了它们的全长编码序列。系统进化分析发现,目标基因均含有NAC家族保守序列且分布在不同系统进化分支。实时荧光定量PCR分析表明,目标基因的表达具有组织特异性且呈现多种盐胁迫应答模式。本研究拟为牧草及作物的分子遗传育种提供基因资源。

Transcription factors play a key regulatory role in plant stress responses. NAC(NAM/ATAF1/2/CUC2) is one of the largest transcription factor families in plants. The functions of NAC involved in salinity stress have been confirmed in many species, but seldom in alfalfa(Medicago sativa). In this study, ten salt-induced NAC transcription factors were characterized by RNA sequencing approach in alfalfa. Their coding sequences were amplified. Phylogenetic analysis revealed that the target genes contain conservative domain but were classified into different phylogenetic branches. Quantitative real-time PCR analysis showed that the expression of target genes was tissue-specific and presents a variety of response patterns under salt stress. This study would provide important genetic resources for molecular genetic breeding of forages and crops.