Key Laboratory of Molecular Design for Plant Cell Factory of Guangdong Higher Education Institutes, Institute of Plant and Food Sciences, Department of Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, 518055, China.
Beijing Key Laboratory of Environment Friendly Management on Fruit Diseases and Pests in North China, Institute of Plant and Environment Protection, Beijing Academy of Agriculture and Forestry Sciences, Beijing, 100097, China.
New Phytol. 2022 Jul;235(1):111-125. doi: 10.1111/nph.17932. Epub 2022 Jan 7.
CONSTITUTIVELY PHOTOMORPHOGENIC 1 (COP1) mediates various cellular and physiological processes in plants by targeting a large number of substrates for ubiquitination and degradation. In this study, we reveal that a substitution of Pro for Leu at amino acid position 409 in WRKY32 largely suppresses the short hypocotyls and expanded cotyledon phenotypes of cop1-6. WRKY32 promotes hypocotyl growth and inhibits the opening of cotyledons in Arabidopsis. Loss of WRKY32 function mutant seedlings display elongated hypocotyls, whereas overexpression of WRKY32 leads to shortened hypocotyls. WRKY32 directly associates with the promoter regions of HY5 to activate its transcription. COP1 interacts with and targets WRKY32 for ubiquitination and degradation in darkness. WRKY32 exhibits enhanced DNA binding ability and affects the expression of more genes compared with WRKY32 in Arabidopsis. Our results not only reveal the basic role for WRKY32 in promoting photomorphogenesis, but also provide insights into manipulating plant growth by engineering key components of light signaling.
组成型光形态建成 1（COP1）通过靶向大量底物进行泛素化和降解，介导植物中的各种细胞和生理过程。在这项研究中，我们揭示了 WRKY32 中第 409 位氨基酸脯氨酸取代亮氨酸，在很大程度上抑制了 cop1-6 的短下胚轴和扩张子叶表型。WRKY32 促进拟南芥下胚轴生长并抑制子叶张开。WRKY32 功能缺失突变体幼苗显示出伸长的下胚轴，而 WRKY32 的过表达导致下胚轴变短。WRKY32 直接与 HY5 的启动子区域结合，激活其转录。COP1 在黑暗中与 WRKY32 相互作用，并将其靶向泛素化和降解。WRKY32 表现出增强的 DNA 结合能力，并影响比拟南芥中 WRKY32 更多的基因表达。我们的研究结果不仅揭示了 WRKY32 在促进光形态建成中的基本作用，而且为通过工程化光信号的关键组件来操纵植物生长提供了思路。
