National Key Laboratory of Plant Molecular Genetics, CAS-JIC Centre of Excellence for Plant and Microbial Science, Center for Excellence in Molecular Plant Sciences (CEPMS), Chinese Academy of Sciences, Shanghai 200032, China.
University of Chinese Academy of Sciences, Beijing 100039, China.
Proc Natl Acad Sci U S A. 2022 Oct 25;119(43):e2202606119. doi: 10.1073/pnas.2202606119. Epub 2022 Oct 17.
The subcellular events occurring in cells of legume plants as they form transcellular symbiotic-infection structures have been compared with those occurring in premitotic cells. Here, we demonstrate that Aurora kinase 1 (AUR1), a highly conserved mitotic regulator, is required for intracellular infection by rhizobia in . AUR1 interacts with microtubule-associated proteins of the TPXL and MAP65 families, which, respectively, activate and are phosphorylated by AUR1, and localizes with them within preinfection structures. MYB3R1, a rhizobia-induced mitotic transcription factor, directly regulates through two closely spaced, mitosis-specific activator elements. Our data are consistent with a model in which the MYB3R1-AUR1 regulatory module serves to properly orient preinfection structures to direct the transcellular deposition of cell wall material for the growing infection thread, analogous to its role in cell plate formation. Our findings indicate that the eukaryotically conserved MYB3R1-TPXL-AUR1-MAP65 mitotic module was conscripted to support endosymbiotic infection in legumes.
作为细胞形成细胞间共生感染结构的亚细胞事件，豆科植物细胞中的这些事件与有丝分裂前细胞中的事件进行了比较。在这里，我们证明高度保守的有丝分裂调节剂 Aurora 激酶 1（AUR1）对于根瘤菌在. 中的细胞内感染是必需的。AUR1 与 TPXL 和 MAP65 家族的微管相关蛋白相互作用，它们分别被 AUR1 激活和磷酸化，并在感染前结构内与它们一起定位。MYB3R1 是一种根瘤菌诱导的有丝分裂转录因子，通过两个紧密间隔的、有丝分裂特异性激活元件直接调控. 我们的数据与一个模型一致，即 MYB3R1-AUR1 调节模块用于正确定位感染前结构，以指导用于生长感染线的细胞壁物质的细胞间沉积，类似于其在细胞板形成中的作用。我们的发现表明，真核生物保守的 MYB3R1-TPXL-AUR1-MAP65 有丝分裂模块被征用来支持豆科植物中的共生感染。
