Brassinosteroid signaling restricts root lignification by antagonizing SHORT-ROOT function in Arabidopsis
Brassinosteroid signaling restricts root lignification by antagonizing SHORT-ROOT function in Arabidopsis
复制标题
油菜素类固醇信号通过拮抗拟南芥中的短根功能来限制根木质化
DOI：
10.1093/plphys/kiac327
复制
发表时间：
2022-08-04
期刊：
影响因子：
7.4
通讯作者：
Wu, Shuang
中科院分区：
文献类型：
--
作者：
Li, Meng;Li, Pengxue;Wu, Shuang
细胞壁木质化是在植物根中形成功能性内胚层和蛋白质（PX）的关键步骤。内胚层中的木质变速带（CS），PX的气盘元素对于选择性吸收和运输水和养分至关重要。尽管已经确定了CS和PX的多个关键调节剂，但将发展向根木质化转移的空间信息仍然未知。在这里，我们发现腕足固醇（BR）信号在抑制根部伸长区的根部木质化方面起着关键作用。 BR信号传导的抑制活性通过抗铜甲唑1（BZR1）与短根（SHR）的直接结合，部分发生，从而抑制了与根木质化有关的SHR介导的下游基因的激活。进入成熟的根部区域后，BR信号传导迅速下降，从而释放SHR活性并引发根部木质化。我们的结果提供了拟南芥根部发育过渡到细胞壁木质化的机械性观点。SHR介导的根木化在空间上通过BZR1与SHR的直接结合而在空间上受到了铜氨基固醇信号的空间限制。
Cell wall lignification is a key step in forming functional endodermis and protoxylem (PX) in plant roots. Lignified casparian strips (CS) in endodermis and tracheary elements of PX are essential for selective absorption and transport of water and nutrients. Although multiple key regulators of CS and PX have been identified, the spatial information that drives the developmental shift to root lignification remains unknown. Here, we found that brassinosteroid (BR) signaling plays a key role in inhibiting root lignification in the root elongation zone. The inhibitory activity of BR signaling occurs partially through the direct binding of BRASSINAZOLE-RESISTANT 1 (BZR1) to SHORT-ROOT (SHR), repressing the SHR-mediated activation of downstream genes that are involved in root lignification. Upon entering the mature root zone, BR signaling declines rapidly, which releases SHR activity and initiates root lignification. Our results provide a mechanistic view of the developmental transition to cell wall lignification in Arabidopsis thaliana roots.SHR-mediated root lignification is spatially restricted by brassinosteroid signaling through the direct binding of BZR1 to SHR.