Elongator mediates ABA responses, oxidative stress resistance and anthocyanin biosynthesis in Arabidopsis.
Elongator mediates ABA responses, oxidative stress resistance and anthocyanin biosynthesis in Arabidopsis.
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DOI：
10.1111/j.1365-313x.2009.03931.x
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发表时间：
2009-10
期刊：
影响因子：
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通讯作者：
Xiaofeng Zhou;Deping Hua;Zhizhong Chen;Zheng Zhou;Z. Gong
中科院分区：
文献类型：
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作者：
Xiaofeng Zhou;Deping Hua;Zhizhong Chen;Zheng Zhou;Z. Gong
伸长子是一种由6个亚基组成的组蛋白乙酰转移酶复合物，在真核生物中高度保守。在这里，我们分离了两个新的突变体，elp2和elp6，在对aba敏感的拟南芥突变体进行遗传筛选。基于图谱的克隆鉴定出了ELP2和ELP6，它们分别编码了酵母伸长子亚基ELP2和ELP6的同源基因。从SALK T-DNA收集中获得了另一个拉长子亚基突变体elp4/elo1。elp1/abo1/elo2突变体是在先前的研究中分离出来的。所有四种伸长突变体都具有叶片狭窄，根生长减少，ABA过敏和花青素积累增加的特点。核心亚复合亚基ELP1/ABO1和ELP2发生突变，而附属亚复合亚基ELP4/ELO1和ELP6不发生突变，导致气孔关闭对ABA异常敏感。此外，这4个突变体对甲基紫病菌产生的氧化应激和CsCl的抗性都比野生型强。基因表达分析表明，这4个突变体在正常条件下CAT3转录水平升高，在ABA处理下ZAT10转录水平升高，MYBL2转录水平降低，MYBL2编码单重复MYB蛋白，是花青素生物合成的负调节因子。研究结果表明，伸长体在调节拟南芥对ABA的响应、抗氧化胁迫和花青素的生物合成中起着重要作用。
Elongator is a histone acetyl-transferase complex consisting of six subunits, and is highly conserved in eukaryotic organisms. Here, we isolated two novel mutants, elp2 and elp6, during a genetic screening for ABA-hypersensitive Arabidopsis mutants. Map-based cloning identified ELP2 and ELP6, which encode the orthologs of the yeast Elongator subunits, ELP2 and ELP6, respectively. Another Elongator subunit mutant, elp4/elo1, was obtained from the SALK T-DNA collection. The elp1/abo1/elo2 mutant was isolated in a previous study. All four of the Elongator mutants had narrow leaves, reduced root growth, ABA hypersensitivity and an increased accumulation of anthocyanins. Mutations in the core subcomplex subunits ELP1/ABO1 and ELP2, but not in the accessory subcomplex subunits ELP4/ELO1 and ELP6, caused stomatal closing to be supersensitive to ABA. In addition, the four mutants were all more resistant than the wild type to oxidative stress produced by methyl viologen, and to CsCl. Gene expression analysis indicated that the four mutants had increased transcript levels of CAT3 under normal conditions, increased transcript levels of ZAT10 when treated with ABA and reduced transcript levels of MYBL2, which encodes a single-repeat MYB protein, acting as a negative regulator of anthocyanin biosynthesis. Our results suggest that Elongator plays crucial roles in regulating plant responses to ABA, oxidative stress resistance and anthocyanin biosynthesis in Arabidopsis.