CYTOPLASMIC EFFECTOR MOLECULES FOR L-SELECTIN

描述（改编自研究者摘要）：白细胞募集 是炎性疾病发病机制的重要组成部分。 调节白细胞募集到炎症部位发生 主要是在内皮细胞的白细胞识别水平， 其由称为选择素的分子家族启动。 这 该提案旨在了解分子和细胞基础， 由L-选择素介导的粘附，L-选择素是白细胞上表达的唯一选择素。 这种粘附分子在所有类型的白细胞上表达， 体内迁移的不同模式，似乎涉及许多 炎症期间白细胞募集的类型。 尽管激烈的 研究表明，由L-选择素介导的粘附的基础仅仅是 部分理解。 我们的初步研究表明， 通过α-辅肌动蛋白和黏着斑蛋白， 对于L-选择素介导的粘附是必需的。 在具体目标1中， L-选择素/α-辅肌动蛋白的分子基础及其功能意义 将研究相互作用。 免疫沉淀和蛋白质印迹， 用各种L-选择素胞质尾突变体转染的细胞系将 用于鉴定L-选择素胞质尾区的残基 负责结合α-辅肌动蛋白和黏着斑蛋白。 功能 这些相互作用的重要性将通过检查 这组转染细胞系结合高内皮细胞的能力 淋巴结小静脉（HEV）和滚动体内，两个最好的特点 以及由L-选择素介导的最重要的功能。 在具体目标2中， 与L-选择素胞质尾区相互作用的其它蛋白质将被 鉴定，并将克隆编码这些蛋白质的cDNA。 在特定 目的3、应用免疫电镜技术探讨其分子基础 和功能的重要性，L-选择素定位到微绒毛， 白细胞，被认为是重要的功能， L-选择素，特别关注涉及的细胞骨架蛋白 in this protein蛋白sorting排序phenomenon现象. 这些研究应该大大增加 我们对L-选择素如何工作的理解， 多个新的临床目标，用于许多急性和慢性疾病的干预 炎症性疾病

DESCRIPTION (Adapted from Investigator's Abstract): Leukocyte recruitment is an essential component of the pathogenesis of inflammatory disorders. The regulation of leukocyte recruitment into sites of inflammation occurs principally at the level of leukocyte recognition of endothelium, a process which is initiated by a family of molecules designated selectins. This proposal is directed at understanding the molecular and cellular basis of adhesion mediated by L-selectin, the only selectin expressed on leukocytes. This adhesion molecule is expressed on all classes of leukocytes, which have distinct patterns of migration in vivo, and appears to be involved in many types of leukocyte recruitment during inflammation. In spite of intense investigation, the basis for adhesion mediated by L-selectin is only partially understood. Our preliminary studies indicate that interactions between L-selectin and the actin cytoskeleton via a-actinin and vinculin are essential for L-selectin mediated adhesion. In specific aim 1, the molecular basis and functional significance of L-selectin/a-actinin interactions will be studied. Immunoprecipitation and Western blotting from cell lines transfected with various L-selectin cytoplasmic tail mutants will be used to identify the residues of the L-selectin cytoplasmic tail responsible for binding to a-actinin and vinculin. The functional significance of these interactions will be determined by examination of the ability of this panel of transfected cell lines to bind to high endothelial venules (HEV) of lymph nodes and to roll in vivo, the two best characterized and most important functions mediated by L-selectin. In specific aim 2, other proteins which interact with the L-selectin cytoplasmic tail will be identified, and cDNA encoding these proteins will be cloned. In specific aim 3, immunoelectron microscopy will be used to explore the molecular basis and functional importance of L-selectin positioning into the microvilli of leukocytes, a location believed to be important to the function of L-selectin, with particular attention to the cytoskeletal proteins involved in this protein sorting phenomenon. These studies should add considerably to our understanding of how L-selectin works, and offer the possibility of multiple new clinical targets for intervention in many acute and chronic inflammatory disorders.