Drought tolerance through overexpression of monoubiquitin in transgenic tobacco
Drought tolerance through overexpression of monoubiquitin in transgenic tobacco
复制标题
DOI：
10.1016/j.jplph.2007.10.002
复制
发表时间：
2008-01-01
影响因子：
4.3
通讯作者：
Wang, Wei
中科院分区：
文献类型：
--
作者：
Guo, Qifang;Zhang, Jin;Wang, Wei
泛素（Ub）存在于真核生物中。它是一种多功能蛋白，其已知的主要功能之一是标记蛋白质，使其被26S蛋白酶体选择性降解。采用逆转录-聚合酶链式反应（RT-PCR）技术从小麦（Triticum aestivum）中分离到一个含有单个Ub重复序列和一个多聚素基因3'非编码区的cDNA序列Ta-UN。构建了含有Ta-Ub2的13131基因表达载体，并将其转化到烟草植株中。利用半定量RT-PCR检测小麦叶片中Ub的表达对干旱胁迫的响应。在转基因烟草中，通过蛋白get blot分析，我们发现与对照（携带不含To-Ub2的PBI GUS载体的烟草）和WT型（WT）相比，ub -蛋白偶联物的数量更高。而游离Ub水平在3个基因型间无显著差异。在干旱和非干旱条件下，转基因、过表达ub的烟草种子比对照和WT样品发芽更快，幼苗生长更旺盛。此外，转基因植株在干旱胁迫下的CO2同化显著提高。我们的研究结果表明，Ub可能参与植物对干旱胁迫的响应，单泛素的过度表达可能是提高植物抗旱性的有效策略。(C) 2007年Elsevier GmbH出版。
Ubiquitin (Ub) is present in at(eukaryotic species examined. It is a multifunctional protein and one of its main known functions is to tag proteins for selective degradation by the 26S proteasome. In this study, Ta-UN, a cDNA sequence containing a single Ub repeat and a 3' non-coding region of a polyubiquitin gene, was isolated from wheat (Triticum aestivum) by reverse transcription-potymerase chain reaction (RT-PCR). A 13131 sense vector with Ta-Ub2 was constructed and transformed into tobacco plants. Ub expression in wheat leaves, monitored by semi-quantitative RT-PCR, responded to drought stress. In transgenic tobacco, determined by protein get blot analysis, we found higher amounts of Ub-protein conjugates than in control (tobacco carrying a PBI GUS vector without To-Ub2) and witd-type (WT) tines. However, free Ub levels did not significantly differ in the 3 genotypes. Seeds from transgenic, Ub-overexpressing tobacco germinated faster and seedlings grew more vigorously than control and WT samples, both under drought and non-drought conditions. Furthermore, CO2 assimilation of transgenic plants was significantly higher under drought stress. Our results indicate that Ub may be involved in the response of plants to drought stress and that overexpression of monoubiquitin might be an effective strategy for enhancing drought tolerance. (C) 2007 Published by Elsevier GmbH.