Regulation of Vascular Eicosanoid Receptors

血管类二十烷酸受体的调节

基本信息

批准号：
6749012
负责人：
EMER MARIA SMYTH
金额：
$ 27.74万
依托单位：
UNIVERSITY OF PENNSYLVANIA
依托单位国家：
美国
项目类别：
财政年份：
2002
资助国家：
美国
起止时间：
2002-07-01 至 2006-06-30
项目状态：
已结题

项目摘要

DESCRIPTION (provided by applicant): Prostacyclin (PG I2) and thromboxane (TxA2), two major cyclooxygenase products formed in the vasculature, exert opposing biological effects. PGI2 is a potent inhibitor of platelet aggregation, vasodilator, anti-thrombotic and anti-mitogen which may be protective in settings of vascular disease. In contrast, TxA2, which induces platelet aggregation, mitogenesis and vasoconstriction, appears to play a detrimental role in the pathogenesis of cardiovascular disorders. Both PGI2 and TxA2 transduce their effects by binding to their cell surface receptors, IP and TP (two splice variants alpha and beta), respectively. IP and TP are frequently co-expressed in cardiovascular cells and elevated PGI2 and TxA2 biosynthesis is coincident in vascular disorders. Cross-regulation of PGI2 and TxA2-responsive events is evident in smooth muscle cells, platelets and other cells types. However, despite our understanding of the regulation and signal transduction pathways utilized by these two systems, little is known about the impact of each signaling cascade on the other. This proposal aims to examine whether and how human (h) IP and hTP activation alone and in concert may modulate each other and seeks to understand the molecular mechanisms attendant to these interactions. We shall address following specific hypotheses.1. That co-activation of hIP and hTP modulates their regulation and G protein coupling. We shall examine heterologous regulation of hIP and hTPalpha/beta in vascular smooth muscle cells endogenously express both receptor types, or deficient in one or the other, and in cell lines expressing the receptors alone or in combination.2. That agonist-induced homo- and hetero- dimerization of IP and TPalpha/beta occurs and has functional and regulatory consequences. We shall examine dimer formation and receptor signaling in vascular smooth muscle cells from humans or cultured from IP or TP deficient mice and in hIP/hTP expressing cell lines.3. That hIP and hIP interact with novel cellular proteins. The role of the cGMP-phosphodiesterase-6 delta subunit, a novel hIP associated factor, in hIP signaling and regulation will be investigated. We shall use yeast-two hybrid technology to screen a vascular smooth muscle cell cDNA library and a proteomic approach to investigate other uncharacterized proteins that interact with hIP or hTP.These studies will define the interaction of two vasoactive eicosanoids at the level of receptor signaling and regulation and identify novel pathways through which G protein-coupled receptors in general, and IP and TP in particular, can heterologously modulate receptor function.

描述（由申请人提供）：前列环蛋白（PG I2）和血栓烷（TXA2），两种主要的环氧酶产物在脉管系统中形成，具有相反的生物学作用。 PGI2是血小板聚集，血管扩张剂，抗脉止性和抗丝质原的有效抑制剂，在血管疾病的环境中可能具有保护作用。相反，诱导血小板聚集，有丝分裂和血管收缩的TXA2似乎在心血管疾病的发病机理中起着不利的作用。 PGI2和TXA2分别与细胞表面受体IP和TP（两个剪接变体Alpha和Beta）结合来传递其效果。 IP和TP经常在心血管细胞中共表达，升高的PGI2和TXA2生物合成在血管疾病中是一致的。 PGI2和TXA2响应事件的交叉调节在平滑肌细胞，血小板和其他细胞中显而易见。但是，尽管我们了解了这两个系统使用的调控和信号转导途径，但对每个信号级联对另一个信号的影响却一无所知。该提案旨在研究人类（H）IP和HTP是否单独激活以及如何共同调节彼此，并试图了解这些相互作用的分子机制。我们将解决以下特定假设1。髋关节和HTP的共同激活调节其调节和G蛋白偶联。我们将检查血管平滑肌细胞中髋关节和htpalpha/beta的异源调节，表达受体类型，或者在一种或另一种中不足，以及单独或组合表达受体的细胞系中。2。激动剂引起的IP和TPALPHA/beta的同型和异差发生发生，并具有功能性和调节后果。我们将检查来自人类的血管平滑肌细胞中的二聚体形成和受体信号传导，或从IP或TP缺乏小鼠以及表达细胞系的HIP/HTP中培养的3。该髋关节和髋关节与新型细胞蛋白相互作用。将研究CGMP-磷酸二酯酶6 Delta亚基（一种新型髋关节相关因子）在髋网信号传导和调节中的作用。 We shall use yeast-two hybrid technology to screen a vascular smooth muscle cell cDNA library and a proteomic approach to investigate other uncharacterized proteins that interact with hIP or hTP.These studies will define the interaction of two vasoactive eicosanoids at the level of receptor signaling and regulation and identify novel pathways through which G protein-coupled receptors in general, and IP and TP in particular, can heterologously调节受体功能。