烟草NtbHLH112基因的克隆、鉴定及表达模式分析

Cloning,Characterization and Expression Pattern Analysis of NtbHLH112 Gene in Nicotiana tabacum

bHLH转录因子在植物响应逆境胁迫过程中起着极为重要的调控作用,克隆和验证烟草中bHLH相关基因可为烟草抗性育种提供理论依据。本研究从普通烟草品种K326中克隆出一个NtbHLH112基因,通过生物信息学方法分析了NtbHLH112功能结构域,利用亚细胞定位及转录激活试验进行了功能鉴定,并利用实时荧光定量PCR(qRT-PCR)分析了其在不同逆境胁迫下的表达模式。结果表明,NtbHLH112具有典型的bHLH结构域且进化较为保守,定位在细胞核,具有转录激活的活性。进化分析表明,NtbHLH112与番茄Slb HLH112和辣椒CabHLH112同源。表达模式分析表明,NtbHLH112基因具有组织表达特异性,在叶部表达量较高,并且受到盐、干旱、冷胁迫及ABA处理诱导。因此,NtbHLH112转录因子可能在烟草非生物胁迫应答过程中发挥重要作用。

The family of bHLH transcription factor plays an important regulatory role in plant response to stress.Cloning and validation of bHLH related genes in tobacco can provide a theoretical basis for tobacco resistance breeding.In this study,we cloned an NtbHLH112 gene from the common tobacco variety K326.To further investigate the function of NtbHLH112,the bioinformatic analysis,subcellular localization and transactivation activity of NtbHLH112 were carried out.We also analyzed the expression pattern of NtbHLH112 under different stress treatments by using qRT-PCR.The results showed that NtbHLH112 had a highly conserved and typical bHLH domain and was localized in nucleus.Moreover,NtbHLH112 had transactivation activity.Phylogenetic analysis suggested that NtbHLH112 was homologous with SlbHLH112 and CabHLH112.The qRT-PCR results demonstrated that NtbHLH112 was highly expressed in leaves and was up-regulated by the treatments of salt stress,high-temperature,cold-temperature and ABA.Therefore,NtbHLH112 as a typical bHLHtranscription factor,may play a significant role in abiotic stress of tobacco.