ENDOTHELIAL ALPHA V INTEGRIN COMPLEXES MODULATED ACTIN CYTOSKELETAL ORGANIZATION

这个子项目是利用资源的许多研究子项目之一。 由NIH/NCRR资助的中心拨款提供。对子项目的主要支持 子项目的首席调查员可能是由其他来源提供的， 包括美国国立卫生研究院的其他来源。为子项目列出的总成本可能 表示该子项目使用的中心基础设施的估计数量， 不是由NCRR赠款提供给次级项目或次级项目工作人员的直接资金。 整合素是细胞表面的受体，具有多种基本的细胞功能。这些功能之一与急性肺损伤等炎症性疾病中发生的器官浮肿有关，是调节液体和溶质通过内皮的调节功能之一，内皮是整个循环系统中排列着血管的细胞层。谢泼德实验室最近证明，α-v整合素通过组织肌动蛋白细胞骨架来调节内皮通透性。具体地说，α-vβ-3整合素是肌动蛋白重排成皮质分布所必需的，它在1-磷酸鞘氨醇(一种血浆介导的屏障增强分子)的作用下增加了血管屏障的强度；另一方面，α-vβ-5是将细胞骨架组织成应力纤维所必需的，后者降低了对凝血酶的屏障强度，凝血酶是一种增加血管泄漏性的血液介质。我们的目标是鉴定与这些整合素相关的蛋白质复合体的成分。在这方面，一个理想的方法是使用质谱学，其中生物化学分离的整合素复合体可以提交给质谱学测序以发现蛋白质。通过这种无偏见的方法，与这两个整合素相关的不同的肌动蛋白结合和/或调节蛋白可能被识别和进一步研究，以了解它们如何调控肌动蛋白组织。有了这些强大的信息，我们可能会进一步剖析介导这两种整合素相反生物反应的途径，并沿着各自的途径靶向特定的点，作为脓毒症和其他急性炎症性疾病中器官水肿的潜在治疗方法。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Integrins are cell surface receptors that serve a number of basic cellular functions. One of these functions, which is relevant to the organ edema that occurs in inflammatory diseases like acute lung injury, is the regulation of passage of fluid and solute across the endothelium, the layer of cells lining blood vessels throughout the circulatory system. The Sheppard lab has recently demonstrated that alpha-v integrins modulate endothelial permeability by organizing the actin cytoskeleton. Specifically, alpha-v beta-3 integrin is necessary for rearrangement of actin into cortical distribution that increases vascular barrier strength in response to sphingosine 1-phosphate, a plasma borne barrier-enhancing molecule; on the other hand, alpha-v beta-5 is required for organization of the cytoskeleton into stress fibers that decrease barrier strength in response to thrombin, a blood borne mediator of increased blood vessel leakiness. Our objective is to identify the constituents of the protein complexes associated with these integrins. An ideal approach in this regard is to employ mass spectrometry, where biochemically isolated integrin complexes can be submitted to mass spectrometric sequencing for protein discovery. With this unbiased approach, the distinct actin binding and/or modulatory proteins associated with these two integrins may be identified and studied further to understand how they modulate actin organization. Armed with this powerful information, we may further dissect pathways mediating the opposing biological response of these two integrins and target specific points along their respective pathways as potential treatments for organ edema in the setting of sepsis and other acute inflammatory diseases.