BBX28/BBX29, HY5 and BBX30/31 form a feedback loop to fine‐tune photomorphogenic development
BBX28/BBX29, HY5 and BBX30/31 form a feedback loop to fine‐tune photomorphogenic development
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BBX28/BBX29、HY5 和 BBX30/31 形成反馈回路以微调光形态发育
DOI：
10.1111/tpj.14929
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发表时间：
2020
期刊：
影响因子：
7.2
通讯作者：
Xing Wang Deng
中科院分区：
文献类型：
--
作者：
Zhaoqing Song;Tingting Yan;Jiujie Liu;Yeting Bian;Yueqin Heng;Fang Lin;Yan Jiang;Xing Wang Deng;Xing Wang Deng
光是控制植物光形态发生发育的关键环境因子之一。一组B-box（BBX）蛋白通过多种调节机制在这一发育过程中发挥关键作用。在这项研究中，我们报告BBX 29作为光信号的负调节剂。BBX 29与组成型光形态发生蛋白1（COP 1）相互作用，并在黑暗中发生COP 1介导的降解。BBX 29功能丧失的突变体幼苗显示缩短的下胚轴，而过表达BBX 29的转基因植物在光照下显示伸长的下胚轴。BBX 28和BBX 29均干扰伸长下胚轴5（HY 5）与BBX 30和BBX 31启动子的结合，从而导致其转录水平上调。BBX 30和BBX 31与BBX 28和BBX 29的启动子区相关，这反过来又促进这些基因的表达。总之，这项研究揭示了一个由BBX 28，BBX 29，BBX 30，BBX 31和HY 5组成的转录反馈环，用于微调植物对光形态建成的响应。
Light is one of the key environmental cues controlling photomorphogenic development in plants. A group of B-box (BBX) proteins play critical roles in this developmental process through diverse regulatory mechanisms. In this study we report that BBX29 acts as a negative regulator of light signaling. BBX29 interacts with CONSTITUTIVELY PHOTOMORPHOGENIC 1 (COP1) and undergoes COP1-mediated degradation in the dark. Mutant seedlings with loss of BBX29 function show shortened hypocotyls, while transgenic plants overexpressing BBX29 display elongated hypocotyls in the light. Both BBX28 and BBX29 interfere with the binding of ELONGATED HYPOCOTYL 5 (HY5) to the promoters of BBX30 and BBX31, consequently leading to the upregulation of their transcript levels. BBX30 and BBX31 associate with the promoter regions of BBX28 and BBX29, which in turn promotes the expression of these genes. Taken together, this study reveals a transcriptional feedback loop consisting of BBX28, BBX29, BBX30, BBX31, and HY5 that serves to fine-tune photomorphogenesis in response to light in plants.