《植物生理学报》 2014, 50(1): 68-76

抑制番茄叶绿体DnaJ蛋白基因的表达降低转基因番茄的抗高温能力

孔凡英, 邓永胜, 尹波, 吕巍, 孟庆伟*

山东农业大学生命科学学院, 作物生物学国家重点实验室, 山东泰安271018

通信作者：孟庆伟；E-mail: qwmeng@sdau.edu.cn；Tel: 0538-8249606

摘　要：

DnaJ蛋白是广泛存在于植物细胞内的一种分子伴侣。在胁迫条件下它能够保护细胞内蛋白质等结构的稳定性。本研究克隆到一个番茄叶绿体DnaJ蛋白基因(LeCDJ1)。半定量PCR分析表明LeCDJ1的表达受NaCl、高温、PEG及ABA的诱导。利用反义抑制的方法获得了LeCDJ1抑制表达的转基因番茄。高温条件下, 转基因株系较野生型表现出较严重的光系统II (PSII)光抑制, 较低的D1蛋白含量, 较高的超氧阴离子(O2 ¯· )、过氧化氢(H₂O₂)含量, 及较低的抗坏血酸过氧化物酶(APX)和超氧化物歧化酶(SOD)活性。这些结果表明, 抑制LeCDJ1的表达降低了转基因番茄的抗高温能力。

关键词：D1蛋白; DnaJ蛋白; 高温胁迫; 光系统II; 活性氧; 番茄

收稿：2013-11-01   修定：2013-11-21

资助：国家重点基础研究发展计划(2009CB118505)和国家自然科学基金(31171474和31371553)

Suppression of a Tomato Chloroplast DnaJ Protein Gene Reduced Heat Tolerance in Transgenic Tomatoes

KONG Fan-Ying, DENG Yong-Sheng, YIN Bo, LÜ Wei, MENG Qing-Wei*

State Key Laboratory of Crop Biology, College of Life Sciences, Shandon Agricultural University, Tai’an, Shandong 271018, China

Corresponding author: MENG Qing-Wei; E-mail: qwmeng@sdau.edu.cn; Tel: 0538-8249606

Abstract:

DnaJ proteins are ubiquitous molecular chaperones contributing to cellular protein conformation stability under stress conditions. In this study, the full length of a tomato chloroplast DnaJ protein gene (LeCDJ1) was cloned and analyzed. The LeCDJ1 expression was up-regulated by NaCl, heat, PEG and ABA. Antisense-mediated suppression of LeCDJ1 transgenic tomato was obtained. The transgenic tomato showed more serious PSII photoinhibition, less D1 protein content, higher superoxide radical (O2 ¯· ) and hydrogen peroxide (H₂O₂) content and lower scorbate peroxidase (APX) and superoxide dismutase (SOD) activity than WT under heat stress. These results indicated that LeCDJ1 suppression reduced heat tolerance in transgenic tomatoes.

Key words: D1 protein; DnaJ protein; heat stress; photosystem II; reactive oxygen species; tomato