蜻蜓凤梨AfDREB2C基因的克隆及乙烯响应特性分析

Isolation and Expression Analysis of AfDERB2C in Aechemia fasciata Treated with Exogenous Ethylene

以重要的热带花卉蜻蜓凤梨(Aechemia fasciata)为材料,基于转录组数据,利用c DNA末端快速扩增(rapid amplification of c DNA ends,RACE)技术克隆了APETALA2/Ethylene Response Element Binding Protein(AP2/EREBP)家族的一个基因,并将其命名为Af DREB2C。Af DREB2C c DNA全长848 bp,有一个594 bp的开放阅读框(open reading frame,ORF),编码197个氨基酸残基。Af DREB2C蛋白分子量为21.498 8 k D,理论等电点为4.65,是一类酸性亲水蛋白,且预测定位于细胞核。实时荧光定量PCR(q RT-PCR)结果表明,Af DREB2C在不同株龄的蜻蜓凤梨不同组织中均有表达,但在很多生殖器官中的表达量很低。此外,Af DREB2C响应了外源乙烯处理,但在成株的不同组织中响应模式不尽相同。本研究为解析Af DREB2C在蜻蜓凤梨生长发育中的机制、为通过基因工程手段调控凤梨科植物生长发育奠定了理论基础。

Aechemia fasciata is a kind of tropical flowering plants with significant economical importance. In this study, a member of APETALA2 / Ethylene Response Element Binding Protein( AP2 / EREBP) family, which was named Af DREB2 C, was isolated from Aechemia fasciata using rapid amplification of c DNA ends(RACE)technology. The full length of Af DREB2 C c DNA was 848 bp, with an open reading frame of 594 bp, encoding a deduced protein of 197 amino acids. The molecular weight of Af DREB2 C was 21.498 8 k D, and the theoretical isoelectric point was 4.65, which classified it as a member of acidic proteins. Besides, Af DREB2 C was predicted to be a hydrophilic and nucleus-localized protein. Quantitative real-time PCR(q RT-PCR) results showed that the transcripts of Af DREB2 C could be detected in all tested vegetative organs either in juvenile plants or in adult plants, but was hardly detectable in many reproductive organs of 39 day after flowering adult plants. Furthermore,the expression of Af DREB2 C transcripts in variable tested organs responsed to exogenous ethylene treatment in different pathways. These results demonstrated that Af DREB2 C might be involved in development of vegetative organs but not floral organs of Aechemia fasciata, providing a theoretical basis of modulating the growth and development of bromeliads using genetic approach in the near future.