MOLECULAR CHARACTERIZATION OF H2 RECEPTOR DUAL SIGNALING

描述（改编自申请人摘要）：这是一项提案， 继续研究胃壁组织中组胺H2受体的信号传导 细胞 主要研究者（PI）及其同事 鉴定了克隆的H2受体的分子结构和功能， 并确定它激活腺苷酸环化酶和磷脂酶C（PLC） 以依赖GTP的霍乱毒素敏感的方式。 这些机制 受体与两个效应系统的偶联仍有待确定。 此外，PI最近发现受体介导细胞凋亡， 早期反应基因的增殖和转录激活， c-fos 在本提案中，将审查以下问题。 （一） 嵌合受体构建体和定点诱变将用于 阐明受体的结构成分与激活 腺苷酸环化酶和磷脂酶C;（2）参与H2的G蛋白 将表征原代和转化细胞中的受体信号传导 使用选择性抗体、免疫印迹、GTP标记和分子标记， 技术;和（3）双重信号的生物学意义将是 探讨了 H2受体/G蛋白靶向寡肽、抗血清和 将使用反义探针来确定 细胞增殖和壁细胞分泌的两条信号通路 活动

DESCRIPTION (Adapted from applicant's abstract): This is a proposal to continue studies on signaling via histamine H2 receptors in gastric parietal cells. The Principal Investigator (PI) and his colleagues have characterized the molecular structure and function of the cloned H2 receptor and determined that it activates adenylate cyclase and phospholipase C (PLC) in a GTP-dependent, cholera toxin-sensitive manner. The mechanisms whereby the receptor couples to two effector systems remain to be determined. Furthermore, the PI has recently found that the receptor mediates cell proliferation and transcriptional activation of the early response gene, c-fos. In the current proposal the following will be examined. (1) Chimeric receptor constructs and site directed mutagenesis will be used to elucidate the structural components of the receptor linked to activation of adenylate cyclase and phospholipase C; (2) the G proteins involved in H2 receptor signaling in primary and transformed cells will be characterized using selective antibodies, immunoblotting, GTP-labeling and molecular techniques; and (3) the biological significance of dual signaling will be explored. H2 receptor/G protein targeted oligopeptides, antisera and antisense probes will be used to determine the relative importance of the two signaling pathways in cell proliferation and parietal cell secretory activity.