COBRE: LSU HSC: P4: ER TO GOLGI T & VSMC

该子项目是利用NIH/NCRR资助的中心赠款提供的资源的许多研究子项目之一。子项目和研究者（PI）可能从另一个NIH来源获得主要资金，因此可以在其他CRISP条目中表示。所列机构为中心，不一定是研究者所在机构。本项目的目的是确定在原代培养的新生大鼠心室肌细胞和血管平滑肌细胞中，血管紧张素II 1型受体（AT 1 R）和β 2肾上腺素能受体（AR）的ER-高尔基体转运改变的作用。有三个具体目标。第一个目的是确定Rab 1和其他囊泡转运调节因子（Sar 1，ARF 1，Rab 2和Rab 6）在内质网到高尔基体转运中的作用。第二个目的是确定是否在ER到高尔基体运输的改变，作为操纵Rab 1功能的结果，参与受体信号传导。第三个目的是确定Rab 1对蛋白表达谱的影响。 在第二年，已经进行了研究，以确定潜在的细胞内运输从ER通过高尔基体的G蛋白偶联受体的细胞表面和它们可能参与心肌细胞肥大的发展的分子机制。我们调查了：（1）Rab 1在新生真菌细胞AT 1 R、α 1-AR和β-AR的转运和信号转导以及肥大反应中的作用。我们已经证明，腺病毒介导的野生型Rab 1的基因转移差异修改AT 1 R，α 1-AR和β-AR以及受体介导的肥大反应的细胞表面靶向和信号传导。(2)二聚化在α 2-AR运输和信号传导中的作用。我们证明了ER输出缺陷的α 2B-AR突变体作为其野生型对应物以及其他α 2-AR的输出和信号传导的显性负突变体起作用。这些数据提供了有关气相化学还原剂出口和功能管理的新的重要信息。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The objective of this project is to determine the role of altered ER-to-Golgi trafficking of angiotensin II type 1 receptor (AT1R) and beta 2 adrenergic receptor (AR) in primary cultures of neonatal rat ventricular myocytes and vascular smooth muscle cells. There are three specific aims. First aim is to define the role of Rab1 and other vesicular transport regulators (Sar1, ARF1, Rab2 and Rab6) in the endoplasmic reticulum-to-Golgi transport. Second aim is to determine if alterations in the ER-to-Golgi transport, as a consequence of manipulating Rab1 function, is involved in receptor signaling. Third Aim is to determine the effect of Rab1 on protein expression profile. In the second year, the studies have been carried out to define the molecular mechanisms underlying the intracellular trafficking from the ER through the Golgi to the cell surface of G protein-coupled receptors and their possible involvement in the development of cardiac myocyte hypertrophy. We have investigated: (1) the role of Rab1 in regulating the transport and signaling of AT1R, alpha1-AR and beta-AR and hypertrophic responses in neonatal mycoytes. We have demonstrated that adenovirus-mediated gene transfer of wild-type Rab1 differentially modified the cell-surface targeting and signaling of AT1R, alpha1-AR and beta-AR as well as receptor-mediated hypertrophic responses. (2) the role of dimerization in alpha2-AR trafficking and signaling. We demonstrated that alpha2B-AR mutant defective in ER export functions as a dominant negative mutant for the export and signaling of its wild-type counterpart as well as other alpha2-AR. These data provide new and important information regarding the regulation of GPCR export and function.