Coxsackie and adenovirus receptor (CAR): a multifunctional cell adhesion molecule

柯萨奇和腺病毒受体（CAR）：多功能细胞粘附分子

基本信息

批准号：
RGPIN-2017-05782
负责人：
Nalbantoglu, Josephine
金额：
$ 2.04万
依托单位：
McGill University
依托单位国家：
加拿大
项目类别：
Discovery Grants Program - Individual
财政年份：
2020
资助国家：
加拿大
起止时间：
2020-01-01 至 2021-12-31
项目状态：
已结题

来源：
https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=711510
关键词：
Coxsackie adenovirus receptor CAR multifunctional

项目摘要

The Coxsackie and adenovirus receptor (CAR) is a member of the immunoglobulin superfamily of adhesion molecules. As its name implies, it was first identified as the high affinity receptor for adenovirus type 5, the most commonly used adenoviral vector for gene transfer. My laboratory's interest in CAR stems from the fact that we routinely use adenovirus (Ad) vectors for gene transfer to muscle, nervous system and tumour cells. As such we have been interested in determining the expression pattern of CAR and means of modulating its expression. In the process, we have started studying the multiple functions of CAR in these tissues. CAR expression is regulated developmentally and in a tissue-specific manner. Ectopic over expression studies in vitro indicate that the extracellular domain of CAR can mediate homotypic cell-cell adhesion. Accordingly CAR is localized to tight and adherens junctions in polarized epithelia. Highest levels of CAR expression are observed in prenatal and neonatal tissues. This pattern of expression suggests CAR could play a role in the growth, migration or differentiation of embryonic or neonatal tissues. Such a role for CAR is further supported by the observation of loss of CAR expression in several types of cancer. We were the first to show that the highly conserved cytoplasmic domain of CAR was essential for regulating cell migration. Through pulldown assays and proteomic analysis we have identified several binding partners, among which were the cytoskeletal proteins tubulin and actin, binding directly to CAR. We have also shown that CAR is processed by metalloproteases, specifically ADAM10, leading to shedding of its extracellular domain. This is followed by cleavage through the gamma-secretase complex to produce an intracellular cytoplasmic fragment, thus generating potentially important signalling molecules. Our long term objective is to understand how an adhesion molecule such as CAR transmits extracellular cues into intracellular signals. In the past few years we have concentrated on two biological systems, tumour cells and neurons. In both cell types, CAR plays crucial roles in cell migration. In tumour cells, CAR expression leads to inhibition of migration and invasion while in neurons, CAR expression promotes process extension (neurite outgrowth). Our specific aims are to: 1) determine the functional relevance of the processing of CAR 2) determine whether CAR's intracellular cytoplasmic domain plays a signaling role 3) study the function of CAR in the developing nervous system

柯萨奇腺病毒受体 (CAR) 是粘附分子免疫球蛋白超家族的成员。顾名思义，它首先被鉴定为 5 型腺病毒的高亲和力受体，5 型腺病毒是最常用的基因转移腺病毒载体。我的实验室对 CAR 的兴趣源于这样一个事实：我们经常使用腺病毒 (Ad) 载体将基因转移到肌肉、神经系统和肿瘤细胞。因此，我们一直对确定 CAR 的表达模式以及调节其表达的方法感兴趣。在此过程中，我们开始研究 CAR 在这些组织中的多种功能。 CAR 表达以组织特异性方式在发育过程中受到调节。体外异位过度表达研究表明，CAR 的胞外结构域可以介导同型细胞间粘附。因此，CAR 定位于极化上皮细胞中的紧密且粘附的连接处。在产前和新生儿组织中观察到最高水平的 CAR 表达。这种表达模式表明 CAR 可能在胚胎或新生儿组织的生长、迁移或分化中发挥作用。在几种类型的癌症中观察到 CAR 表达缺失，进一步支持了 CAR 的这种作用。我们是第一个证明 CAR 高度保守的胞质结构域对于调节细胞迁移至关重要的人。通过 Pulldown 分析和蛋白质组分析，我们鉴定了几种结合伙伴，其中包括直接与 CAR 结合的细胞骨架蛋白微管蛋白和肌动蛋白。我们还表明，CAR 由金属蛋白酶（特别是 ADAM10）加工，导致其胞外结构域脱落。随后通过γ-分泌酶复合物进行裂解，产生细胞内的细胞质片段，从而产生潜在的重要信号分子。我们的长期目标是了解 CAR 等粘附分子如何将细胞外信号传递为细胞内信号。在过去的几年里，我们主要关注两个生物系统：肿瘤细胞和神经元。在这两种细胞类型中，CAR 在细胞迁移中发挥着至关重要的作用。在肿瘤细胞中，CAR 表达会抑制迁移和侵袭，而在神经元中，CAR 表达会促进过程延伸（神经突生长）。我们的具体目标是： 1）确定CAR处理的功能相关性 2）确定CAR的胞内胞质结构域是否起到信号传导作用 3）研究CAR在神经系统发育中的功能