Institute for Developmental Biochemistry, Medical School, University of Göttingen, 37077 Göttingen, Germany.
Institute for Developmental Biochemistry, Medical School, University of Göttingen, 37077 Göttingen, Germany
J Cell Sci. 2018 Apr 4;131(7):jcs212795. doi: 10.1242/jcs.212795.
Underlying the plasma membrane of eukaryotic cells is an actin cortex that includes actin filaments and associated proteins. A special feature of all polarized and epithelial cells are cortical domains, each of which is characterized by specific sets of proteins. Typically, an epithelial cell contains apical, subapical, lateral and basal domains. The domain-specific protein sets contain evolutionarily conserved proteins, as well as cell-type-specific factors. Among the conserved proteins are, the Par proteins, Crumbs complex and the lateral proteins Scribbled and Discs large 1. Organization of the plasma membrane into cortical domains is dynamic and depends on cell type, differentiation and developmental stage. The dynamics of cortical organization is strikingly visible in early embryos, which increase the number of distinct cortical domains from one, during the pre-blastoderm stage, to two in syncytial blastoderm embryos, before finally acquiring the four domains that are typical for epithelial cells during cellularization. In this Review, we will describe the dynamics of cortical organization in early embryos and discuss the processes and mechanisms underlying cortical remodeling.
真核细胞的质膜下有一层肌动蛋白皮质，其中包括肌动蛋白丝和相关蛋白。所有极化和上皮细胞的一个显著特征是皮质域，每个皮质域都有其特定的蛋白质组。通常，上皮细胞包含顶、亚顶、侧和基底域。域特异性蛋白组包含进化上保守的蛋白，以及细胞类型特异性的因子。在保守蛋白中，有 Par 蛋白、Crumb 复合物以及侧向蛋白 Scribbled 和 Discs large 1。质膜的皮质域组织是动态的，取决于细胞类型、分化和发育阶段。皮质组织的动力学在早期胚胎中非常明显，在原肠胚阶段之前，从一个独特的皮质域增加到合胞体胚盘中的两个皮质域，然后在细胞化过程中最终获得上皮细胞的四个典型皮质域。在这篇综述中，我们将描述早期胚胎中皮质组织的动力学，并讨论皮质重塑的过程和机制。
