Histidine kinase MHZ1/OsHK1 interacts with ethylene receptors to regulate root growth in rice
Histidine kinase MHZ1/OsHK1 interacts with ethylene receptors to regulate root growth in rice
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DOI：
10.1038/s41467-020-14313-0
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发表时间：
2020-01
影响因子：
16.6
通讯作者：
He Zhao;Kai-Xuan Duan;B. Ma;C. Yin;Yang Hu;Jian-Jun Tao;Yi-Hua Huang;Wu-Qiang Cao;Hui Chen;Chao Yang;Zhiguo Zhang;Si-Jie He;Wan-Ke Zhang;Xiang-Yuan Wan;Tie-gang Lu;S. Chen;Jin‐Song Zhang
中科院分区：
文献类型：
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作者：
He Zhao;Kai-Xuan Duan;B. Ma;C. Yin;Yang Hu;Jian-Jun Tao;Yi-Hua Huang;Wu-Qiang Cao;Hui Chen;Chao Yang;Zhiguo Zhang;Si-Jie He;Wan-Ke Zhang;Xiang-Yuan Wan;Tie-gang Lu;S. Chen;Jin‐Song Zhang
乙烯在水稻对水饱和环境的适应性反应中起着至关重要的作用，但对其信号传导机制的了解仍然有限。通过对水稻乙烯响应突变体mhz1的分析，我们发现mhz1正向调节根对乙烯的响应。mhz1编码水稻组氨酸激酶OsHK1。MHZ1/OsHK1在保守的组氨酸残基上进行自磷酸化，并可通过磷酸化转移蛋白OsAHP1/2将磷酸化信号传递给应答调节因子OsRR21。这种磷接力途径是根对乙烯反应所必需的。乙烯受体OsERS2通过其GAF结构域与MHZ1/OsHK1物理相互作用并抑制其激酶活性。遗传分析表明，MHZ1/OsHK1在乙烯感知水平上起作用，并与osein2介导的途径一起调节根的生长。我们的研究结果表明，MHZ1/OsHK1部分独立于OsEIN2介导乙烯应答，并直接受到乙烯受体的抑制，从而揭示了乙烯信号调控根生长的机制细节。
Ethylene plays essential roles during adaptive responses to water-saturating environments in rice, but knowledge of its signaling mechanism remains limited. Here, through an analysis of a rice ethylene-response mutantmhz1, we show thatMHZ1positively modulates root ethylene responses.MHZ1encodes the rice histidine kinase OsHK1. MHZ1/OsHK1 is autophosphorylated at a conserved histidine residue and can transfer the phosphoryl signal to the response regulator OsRR21 via the phosphotransfer proteins OsAHP1/2. This phosphorelay pathway is required for root ethylene responses. Ethylene receptor OsERS2, via its GAF domain, physically interacts with MHZ1/OsHK1 and inhibits its kinase activity. Genetic analyses suggest that MHZ1/OsHK1 acts at the level of ethylene perception and works together with the OsEIN2-mediated pathway to regulate root growth. Our results suggest that MHZ1/OsHK1 mediates the ethylene response partially independently of OsEIN2, and is directly inhibited by ethylene receptors, thus revealing mechanistic details of ethylene signaling for root growth regulation.