Orchestration of microtubules and the actin cytoskeleton in trichome cell shape determination by a plant-unique kinesin.
Orchestration of microtubules and the actin cytoskeleton in trichome cell shape determination by a plant-unique kinesin.
复制标题
通过植物独特的驱动蛋白确定毛状体细胞形状中微管和肌动蛋白细胞骨架的编排
作者：
Tian J;Han L;Feng Z;Wang G;Liu W;Ma Y;Yu Y;Kong Z
微管（MT）和肌动蛋白丝（F-actin）共同调控植物细胞的形态发生。然而，这两个细胞骨架系统之间的串扰的机制，特别是在细胞形状控制，仍然在很大程度上未知。在这项研究中，我们表明，在进化过程中，将MyTH 4-FERM串联引入KCBP（驱动蛋白样钙调素结合蛋白）赋予了新的功能。KCBP N-末端尾部的MyTH 4结构域和FERM结构域分别与MT和F-肌动蛋白物理结合。在毛状体形态发生过程中，KCBP以特定的皮层梯度分布，并集中在缺乏MT但具有皮层F-actin的分支部位和伸长分支的顶端。此外，活细胞成像和遗传分析表明，KCBP作为一个枢纽整合MT和肌动蛋白丝组装所需的细胞骨架配置的独特的，极化的弥漫性生长模式在毛状体细胞形态发生。我们的研究结果提供了重要的见解的细胞骨架调节细胞形状决定的机制。DOI：http://dx.doi.org/10.7554/eLife.09351.001网站
Microtubules (MTs) and actin filaments (F-actin) function cooperatively to regulate plant cell morphogenesis. However, the mechanisms underlying the crosstalk between these two cytoskeletal systems, particularly in cell shape control, remain largely unknown. In this study, we show that introduction of the MyTH4-FERM tandem into KCBP (kinesin-like calmodulin-binding protein) during evolution conferred novel functions. The MyTH4 domain and the FERM domain in the N-terminal tail of KCBP physically bind to MTs and F-actin, respectively. During trichome morphogenesis, KCBP distributes in a specific cortical gradient and concentrates at the branching sites and the apexes of elongating branches, which lack MTs but have cortical F-actin. Further, live-cell imaging and genetic analyses revealed that KCBP acts as a hub integrating MTs and actin filaments to assemble the required cytoskeletal configuration for the unique, polarized diffuse growth pattern during trichome cell morphogenesis. Our findings provide significant insights into the mechanisms underlying cytoskeletal regulation of cell shape determination. DOI: http://dx.doi.org/10.7554/eLife.09351.001