《植物生理学报》 2018, 54(3): 386-392

拟南芥dmard abf3突变体对ABA的敏感性和耐旱性能

黄淑颜, 冯锦欣, 陈家逸, 盘诗雨, 张裕敏, 陈健璞, 李玲^*, 李晓云^*

华南师范大学生命科学学院, 广东省植物发育生物工程重点实验室, 广州510631

通信作者：李；E-mail: liling502@126.com, xiaoyun5893@163.com

摘　要：

本研究课题组在前期研究中通过T-DNA插入突变获得了拟南芥(Arabidopsis thaliana)突变体dmard, 其根生长对ABA超敏感。将突变体dmard与abf3杂交, 进一步分析双突变体对ABA敏感性和耐旱性能, 以确定其在ABA信号通路中的作用。结果表明, ABA处理下, dmard abf3的绿胚率及根生长与野生型(Col)无显著差异, ABA敏感性低于dmard而高于abf3。干旱-复水实验结果表明, dmard abf3的存活率与Col接近, 均低于dmard高于abf3, dmard abf3植株体内活性氧(ROS)含量和超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、过氧化物酶(POD)活性均恢复至Col水平。dmard abf3双突变体中ABF3、RD29A、RD29B基因表达与Col相似, 在abf3中这3个基因表达均下调, dmard中均上调。以上实验表明, dmard部分恢复abf3对ABA的敏感性及抗旱抗氧化的能力, 推测DMARD是ABA信号中的一个负调控因子, 位于ABF3的遗传上位。

关键词：拟南芥; dmard abf3突变体; ABA敏感性; 耐旱性能

收稿：2018-01-04   修定：2018-02-28

资助：国家自然科学青年基金项目(31501167)、广东省自然科学基金项目(2015A030310457)、广东省大学生科技创新培育专项资金立项项目(pdjh2016b0142)、华南师范大学创新训练项目(20160517)。

ABA sensitivity and drought tolerance of Arabidopsis dmard abf3 mutant

HUANG Shu-Yan, FENG Jin-Xin, CHEN Jia-Yi, PAN Shi-Yu, ZHANG Yu-Min, CHEN Jian-Pu, LI Ling^*, LI Xiao-Yun^*

Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou 510631, China

Corresponding author: LI Ling; E-mail: liling502@126.com, xiaoyun5893@163.com

Abstract:

In previous study, an Arabidopsis thaliana loss-of-function mutant dmard (defective mitochondrial transcription termination factor acquire resistance to drought) was obtained through a T-DNA insertion mutation screening, and the root growth of dmard was hypersensitive to ABA. To further determine the function of DMARD gene, ABA response and drought tolerance were observed in the double mutant, which was made by crossing dmard with the abf3, an ABA response element binding factor 3 gene defective mutant. The results showed that under the treatment of ABA, the green embryo rate and root growth of seedlings were not significantly different between the dmard abf3 and Col, while dmard abf3 was lower than dmard and higher than abf3. The drought resistance of dmard abf3 was lower than that of dmard and higher than that of abf3, but dmard abf3 was similar to Col, according to the survival rate of plants under drought-rehydration treatment. Furthermore, the content of reactive oxygen species (ROS) and activities of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) were detected in dmard abf3 and Col plants, indicating that antioxidant level of dmard abf3 was close to that of Col. Besides, the expression levels of ABF3, RD29A and RD29B genes were also recovered to Col in dmard abf3, while all of these genes were upregulated in dmard and were downregulated in abf3. Taken together, the ABA response and antioxidant ability of abf3 were partly restored by losing of DMARD function, which indicates that DMARD is a negative feedback factor in ABA signalling and epistatic to ABF3.

Key words: Arabidopsis; dmard abf3 mutant; ABA sensitivity; drought resistance