The Specification of Geometric Edges by a Plant Rab GTPase Is an Essential Cell-Patterning Principle During Organogenesis in Arabidopsis.
The Specification of Geometric Edges by a Plant Rab GTPase Is an Essential Cell-Patterning Principle During Organogenesis in Arabidopsis.
复制标题
DOI：
10.1016/j.devcel.2016.01.020
复制
发表时间：
2016-02-22
影响因子：
11.8
通讯作者：
Moore I
中科院分区：
文献类型：
--
作者：
Kirchhelle C;Chow CM;Foucart C;Neto H;Stierhof YD;Kalde M;Walton C;Fricker M;Smith RS;Jérusalem A;Irani N;Moore I
植物器官发生需要控制分裂平面和各向异性细胞壁生长，这两者都需要细胞的空间图案。多面体植物细胞可以表现出复杂的图案，其中各个面通过内膜运输建立为生化上不同的域。我们现在表明，在器官发生过程中，拟南芥内膜系统指定了一个重要的附加细胞空间域：几何边缘。通过 RAB-A5c（膜运输调节子 Rab 家族的植物 GTP 酶）的定位，揭示了位于细胞边缘质膜正下方的先前未识别的膜囊泡。 RAB-A5c 活性的特异性抑制通过独立干扰生长各向异性和胞质分裂而不破坏默认的膜运输，严重扰乱了发育中的侧器官的细胞几何形状。正常细胞几何形状的最初损失可以通过未能维持特别是在几何边缘处的壁刚度来解释。因此，RAB-A5c 满足在器官发生过程中指定该细胞空间域的要求。植物细胞拥有一类离散的囊泡，标记其几何边缘 这些囊泡由植物特有的 Rab GTPase 变体定义 抑制这种 GTPase 的活性会破坏生长各向异性和形态发生 边缘定向交通是一个重要的图案形成原理，增强面部极性 器官发生需要植物细胞通过个体上共享壁的协调各向异性生长来调整其形状 多面体面。基尔希勒等。 等人。现在表明，细胞的几何边缘代表了一个额外且重要的空间域，由对形态发生至关重要的植物 Rab GTPase 活性指定。
Plant organogenesis requires control over division planes and anisotropic cell wall growth, which each require spatial patterning of cells. Polyhedral plant cells can display complex patterning in which individual faces are established as biochemically distinct domains by endomembrane trafficking. We now show that, during organogenesis, the Arabidopsis endomembrane system specifies an important additional cellular spatial domain: the geometric edges. Previously unidentified membrane vesicles lying immediately beneath the plasma membrane at cell edges were revealed through localization of RAB-A5c, a plant GTPase of the Rab family of membrane-trafficking regulators. Specific inhibition of RAB-A5c activity grossly perturbed cell geometry in developing lateral organs by interfering independently with growth anisotropy and cytokinesis without disrupting default membrane trafficking. The initial loss of normal cell geometry can be explained by a failure to maintain wall stiffness specifically at geometric edges. RAB-A5c thus meets a requirement to specify this cellular spatial domain during organogenesis. Plant cells possess a discrete class of vesicles that marks their geometric edges These vesicles are defined by a Rab GTPase variant that is unique to plants Inhibiting the activity of this GTPase disrupts growth anisotropy and morphogenesis Edge-directed traffic is a crucial patterning principle, augmenting facial polarity Organogenesis requires plant cells to adjust their shape through coordinated anisotropic growth of shared walls on individual polyhedral faces. Kirchhelle et. al. now show that the geometric edges of cells represent an additional and important spatial domain, specified by a plant Rab GTPase activity that is essential for morphogenesis.