木薯MeNAC29、MeNAC30基因的克隆及表达分析

Cloning and Expression Analysis of Cassava Me NAC29 and Me NAC30 Genes

NAC(NAM/ATAF/CUC)基因家族是广泛分布于陆生植物的一类转录因子,在植物生长发育和胁迫应答的调控中发挥重要作用。本文对该基因家族在木薯抗细菌性萎蔫病方面的作用机制进行了初步研究。采用RT-PCR技术从木薯cDNA中克隆了MeNAC29和MeNAC30基因,并采用qRT-PCR技术对抗、感种质受木薯萎蔫病菌(Xanthomonas axonopodispv.manihotis,Xam)侵染后2个基因的表达变化进行了定量分析。结果表明,2个基因均含有3个外显子和2个内含子,且均有保守的NAM结构域。MeNAC29基因的开放阅读框全长888 nt,编码295 aa。MeNAC30基因的开放阅读框全长870 nt,编码289 aa。接种木薯萎蔫病菌后,抗病种质中MeNAC29和MeNAC30基因的表达量显著高于感病品种,表明这2个基因参与了木薯对细菌性萎蔫病菌的抗性反应。

The NAC (NAM/ATAF/CUC) transcription factor gene family was widely distributed in terrestrial plants and plays an important role in the regulation of growth and stress responses. The preliminary research about the role of this gene family on the cassava against bacterial blight was carried out in our lab. Two genes, MeNAC29 and MeNAC30, were cloned from cassava cDNA by RT-PCR, the different expression changes between resistant and susceptible cassava germplasms infected by Xanthomonas axonopodis pv. manihotis (Xam) were also quantified by qRT-PCR. The results showed both MeNAC29 and MeNAC30 contain three exons, two introns, and conserved NAM domain. The length of MeNAC29 gene’s ORF was 888 nt, which encode 295 amino acids, while the MeNAC30 gene’s ORF was 870 nt and encode 289 amino acids. Compared with susceptible cassava germplasms, both two genes’ expression was significantly increased in the resistant cassava germplasms - Xanthomonas axonopodis pv. manihotis interaction, which showed they are involved in resistance response of cassava to bacterial blight.