Regulation of Membrane-Cortical Cytoskeleton Crosstalk by WASH

描述（由申请人提供）：质膜和底层皮质细胞骨架经历持续的动态相互作用，这是许多基本细胞过程所必需的，包括信号转导、迁移、内/外细胞作用以及细胞间和细胞内的附着/粘附。因此，调节这些相互作用及其功能的蛋白质在生物学中具有普遍的重要性。Wiskott Aldrich综合征（WAS）蛋白家族作为Rho家族GTPases的效应器，通过Arp2/3复合物聚合肌动蛋白。WAS家族的两个创始成员WASP和SCAR/WAVE参与膜-细胞骨架相互作用，这些相互作用对膜/囊泡运输、形态发生、血管生成、炎症免疫反应等过程至关重要，当调节不当时，还会导致病原体感染、出血/瘀伤、免疫缺陷和癌症转移。我们最近确定了WAS家族蛋白的第三个亚家族，称为WASH，它从内阿米巴原虫到人类都是保守的。这项建议的长期目标是描述WASH的细胞质和细胞核功能以及这些过程出错的发育后果。本提案的具体目标是：1)利用遗传、发育、分子/生化和细胞生物学方法确定WASH在肌动蛋白和微管细胞骨架协调以及细胞骨架-膜串扰调控中的作用；2)阐明WASH在血细胞发育和趋化迁移中的作用机制；3)结合比较生物信息学、细胞生物学和高分辨率显微方法，研究WASH对核结构和组织的影响。丰富的技术、复杂的实时成像和在果蝇中可用的试剂使其成为研究体内WASH功能的优秀的、遗传可操作的生物。从这些项目中获得的结果预计将具有广泛的意义，因为WASH在整个生物体中都是保守的。WASH还将作为揭示其他肌动蛋白结合蛋白和细胞质（细胞骨架）蛋白/家族的一般组织原理和/或作用机制的参考蛋白，并将为控制核内外普遍分子和细胞生物学事件的机制提供新的见解。在这些项目中收集的信息对于了解WASH如何控制正常发育或疾病状态下的关键细胞过程非常重要，从长远来看，对于新型抗疾病药物和/或治疗方法的潜在开发或增强现有治疗方法的有效性非常重要。

DESCRIPTION (provided by applicant): The plasma membrane and the underlying cortical cytoskeleton undergo continuous dynamic interplay that is necessary for many essential cellular processes, including signal transduction, migration, endo-/exo-cytosis, and inter- and intra-cellular attachments/adhesion. Thus, the proteins that regulate these interactions and their function are of general importance in biology. The Wiskott Aldrich Syndrome (WAS) protein family, which act as effectors of Rho family GTPases, polymerize actin through the Arp2/3 complex. The two founding WAS family members, WASP and SCAR/WAVE, are involved in membrane-cytoskeletal interactions important for processes including membrane/vesicle trafficking, morphogenesis, angiogenesis, inflammatory immune response, and when mis-regulated, in pathogen infection, bleeding/bruising, immune deficiency and cancer metastasis. We have recently identified a third subfamily of WAS family proteins, designated WASH, that is conserved from Entamoeba to humans. The long-term goal of this proposal is to delineate both the cytoplasmic and nuclear function(s) of WASH and the developmental consequences of these processes going awry. The specific aims of this proposal are 1) to determine the role(s) of WASH in the regulation of actin and microtubule cytoskeletal coordination and cytoskeletal-membrane crosstalk using genetic, developmental, molecular/biochemical, and cell biological approaches; 2) to delineate the mechanisms of WASH function in hemocyte developmental and chemotactic migrations; and 3) to investigate the effect of WASH on nuclear architecture and organization using a combination of comparative bioinformatic, cell biological, and high-resolution microscopic approaches. The wealth of techniques, sophisticated live imaging, and reagents available in Drosophila make it an excellent, genetically manipulable, organism for studying the functions of WASH in vivo. Results obtained from these projects are expected to have wide implications as WASH is conserved throughout organisms. WASH will also serve as a reference protein for revealing general organizational principles and/or mechanisms for the roles of other actin-binding and cytoplasmic (cytoskeletal) proteins/families and will provide new insight into mechanisms controlling universal molecular and cell biological events both in and out of the nucleus. The information gathered in these projects will be important for understanding how WASH functions to control key cellular processes in normal development or when mis-regulated in disease states, and in the longer term, for the potential development of novel anti- disease drugs and/or therapies, or to enhance the effectiveness of existing treatments.