文档介绍：获得 T2 代的转基因烟草植株。表型分析的结果表明,过表达 TaAQP8 能够增强转基
因烟草对干旱胁迫的耐受能力。生理分析结果表明,在干旱胁迫处理条件下,转基因烟草植株比野生型具有较高的相对水含量(Relative water content,RWC),较低的离子渗漏(Ion leakage,IL)、较低的丙二醛(Malondialdehyde,MDA)含量。以上结果均表明,过表达 TaAQP8 使转基因植株能更好的对抗干旱所致的胁迫损伤。
(4) TaAQP8 转基因烟草对渗透胁迫的耐受性分析
分析在高渗的 MS 培养基上转基因烟草的根长和种子的发芽率,结果表明过表达 TaAQP8 降低了渗透胁迫对转基因烟草根长和发芽的抑制,过表达 TaAQP8 可以增强转基因烟草植株对渗透胁迫导致的胁迫损伤的耐受能力。
综上结果,本研究的主要结论是从小麦中克隆了一个水通道蛋白基因 TaAQP8, 将 TaAQP8 基因转烟草,得到转基因的烟草来研究该基因的功能,证明 TaAQP8 作为一个通过调控抗胁迫防御相关基因的表达赋予植物对干旱、渗透胁迫的耐受性。
关键词:小麦;烟草;TaAQP8 基因;水通道蛋白;表达分析;干旱胁迫耐受
Abstract
Aquaporins are channel-forming membrane proteins with the extraordinary ability bine a high flux with a high specificity for water across biological membranes. They belong to the major intrinsic proteins (MIPs) with molecular weights in the range of 23-31 kD, with members found in nearly all anisms. Regulation of aquaporin mediated water flow, appears to be a mechanism by which plants can control water or other small molecules movement. Plant aquaporins play an important role in many physiological
processes , including photosynthesis, mineral nutrition, stoma on-off, germination,
flowering, fruit development and environmental responses.
This work is mainly about the cloning and functional analysis of wheat aquaporin gene, TaAQP8. The main results are as follows:
Using the knowledge of bioinformatics,searched for the EST sequence of TaAQP8,
based on the specific primers and obtained the full-length cDNA by RACE-PCR.
By bioinformatic analysis, full-length of TaAQP8 cDNA sequence had a 909 bp open reading predicted TaAQP8 protein contained six putative transmembrane
α-helices,a highly conserved amino acid sequence ‗HINPAVTFG‘, and two ‗NPA‘ motifs.
TaAQP8 belonged to PIP1 subfamily. Blastx analysis showed that TaAQP8 shared a high degree of sequence similarity with AQPs from other plant species: 98 % sequence identity with HvPIP1-1 from Hordeum vulgare, 56 % with ZmPIP1-1 from Zea mays.
Using the Real-time quantitative PCR to