AtHB7/12 Regulate Root Growth in Response to Aluminum Stress
AtHB7/12 Regulate Root Growth in Response to Aluminum Stress
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DOI：
10.3390/ijms21114080
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发表时间：
2020-06-01
影响因子：
5.6
通讯作者：
Ding, Zhaojun
中科院分区：
文献类型：
--
作者：
Liu, Yang;Xu, Jiameng;Ding, Zhaojun
铝（Al）胁迫是酸性土壤中植物生长和作物生产的主要限制因素。目前，仅对少数参与铝抗性调节的转录因子进行了表征。在这里，我们使用反向遗传方法，通过过表达子和突变体的表型分析来证明 AtHB7 和 AtHB12 这两个 HD-Zip I 转录因子参与 Al 抗性。响应铝胁迫，AtHB7 和 AtHB12 显示出不同的动态表达模式。尽管AtHB7和AtHB12在没有Al胁迫的情况下都积极调节根系生长，但我们的结果表明AtHB7与AtHB12拮抗以响应Al胁迫来控制根系生长。 athb7/12 双突变体在铝胁迫下表现出野生型表型。一致地，我们的生理分析表明AtHB7和AtHB12相反地调节细胞壁结合Al的能力。酵母双杂交实验表明AtHB7和AtHB12在体外可以形成同源二聚体和异源二聚体，表明AtHB7和AtHB12在根生长调节中存在相互作用。结论是AtHB7和AtHB12通过影响根细胞壁铝积累而反向调节铝抗性。
Aluminum (Al) stress is a major limiting factor for plant growth and crop production in acid soils. At present, only a few transcription factors involved in the regulation of Al resistance have been characterized. Here, we used reversed genetic approach through phenotype analysis of overexpressors and mutants to demonstrate that AtHB7 and AtHB12, two HD-Zip I transcription factors, participate in Al resistance. In response to Al stress, AtHB7 and AtHB12 displayed different dynamic expression patterns. Although both AtHB7 and AtHB12 positively regulate root growth in the absence of Al stress, our results showed that AtHB7 antagonizes with AtHB12 to control root growth in response to Al stress. The athb7/12 double mutant displayed a wild-type phenotype under Al stress. Consistently, our physiological analysis showed that AtHB7 and AtHB12 oppositely regulate the capacity of cell wall to bind Al. Yeast two hybrid assays showed that AtHB7 and AtHB12 could form homo-dimers and hetero-dimers in vitro, suggesting the interaction between AtHB7 and AtHB12 in the regulation of root growth. The conclusion was that AtHB7 and AtHB12 oppositely regulate Al resistance by affecting Al accumulation in root cell wall.