Human Choriogonadotropin Signaling in Cell Proliferation

细胞增殖中的人绒毛膜促性腺激素信号转导

• 批准号: 6506623
• 负责人: OM P BAHL
• 金额: $ 7.8万
• 依托单位: STATE UNIVERSITY OF NEW YORK AT BUFFALO
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-08-01 至 2004-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6506623
• 关键词: biological signal transduction; cell growth regulation; cell line; cell proliferation; chorionic gonadotropin; enzyme activity; epidermal growth factor; gene expression; growth factor receptors; hormone receptor; hormone regulation /control mechanism; human genetic material tag; immunoprecipitation; luteinizing hormone; microarray technology; mitogen activated protein kinase; receptor binding; transfection

DESCRIPTION (provided by applicant): hCG plays a key role in human reproduction and is produced during the first trimester of pregnancy. It is also produced by a variety of tumors including choriocarcinoma, hydatidiform mole, and embryonic carcinoma of the testis. Structurally, hCG is similar in some respects to tumor growth factor (TGF)-Beta, nerve growth factor (NGF) and platelet-derived growth factor (PDGF)-Beta. All of them contain cystine knot motif and have been implicated in the development of a variety of tumors. hCG stimulates cell growth and differentiation and, therefore, it is highly likely that its function is regulated by the three member MAK kinase cascade, mitogen-activated protein kinase-kinase-kinase (MAPKKK)--MAPKK-extracellular signal-regulated kinase (ERK). The objectives of the proposed studies are to investigate the involvement of the MAP kinase pathway in the cell growth and differentiation by hCG. Pathway-specific DNA microarray technology will be employed to compare the gene expression profiles of hCG and epidermal growth factor (EGF) signaling when they interact with their respective receptors in signaling in a rat SIGC-hCG/; lutropin receptor (LHR) and SIGC-epidermal growth factor receptor (EGFR). This should give us some information on the expression of genes that are common to both signaling pathways. The signaling proteins downstream of ERK and upstream of MAPKKK will be investigated. Lastly, search for a scaffold protein on which these kinases might be organized will be made. The studies will be carried out with the rat SIGC. SIGC has an epithelial morphology and grows in culture without luteinization. Specific short-term goals of the initial studies will include: 1) Transfection of rat SIG cells with hCG/LH and EGF receptor cDNAs separately and selection of stable transfectants, SIGC-hCG/LHR and SIGC-EGFR; 2) Preliminary characterization of SIGC-hCG/LHR and SIGC-EGFR, which will involve a) determination of the presence and concentration of hCG/LH and EGF receptors by binding assays using 125IhCG and 125IEGF and b) study of the effect of hCG on the activation of adenylyl cyclase and phospholipase C and of EGF on the activation of receptor tyrosine kinase; 3) Study the effect of hCG and EGF on the activities of Raf, MEK and ERK; 4) Comparison of the gene expression profiles of signaling by hCG and EGF in SIGC-hCG/LHR and SIGC-EGFR by DNA microarrays; 5) Determination of the downstream and upstream signaling proteins of ERK and Raf kinases respectively by association or immunoprecipitation techniques using specific polyclonaI antibodies; and 6) Search for a scaffold protein for MAP kinase module will be made.

描述（由申请人提供）：hCG在人类生殖中起着关键作用，并在妊娠的前三个月产生。 它也由多种肿瘤产生，包括绒毛膜癌、葡萄胎和睾丸胚胎癌。 在结构上，hCG在某些方面类似于肿瘤生长因子（TGF）-β，神经生长因子（NGF）和血小板衍生生长因子（PDGF）-β。 它们都含有胱氨酸结基序，并与多种肿瘤的发生有关。 hCG刺激细胞生长和分化，因此，它的功能很可能是由三个成员的MAK激酶级联调节，丝裂原活化蛋白激酶-激酶-激酶（MAPKKK）-MAPKK-细胞外信号调节激酶（ERK）。 本研究的目的是探讨MAP激酶通路在hCG诱导的细胞生长和分化中的作用。 将采用途径特异性DNA微阵列技术来比较hCG和表皮生长因子（EGF）信号传导的基因表达谱，当它们在大鼠SIGC-hCG/促黄体激素受体（LHR）和SIGC-表皮生长因子受体（EGFR）中与它们各自的信号传导受体相互作用时。 这应该给我们一些关于两种信号通路共有基因表达的信息。 ERK下游和MAPKKK上游的信号蛋白将被研究。 最后，寻找这些激酶可能组织的支架蛋白。 将使用大鼠SIGC进行研究。 SIGC具有上皮形态，并且在培养物中生长而没有黄素化。 初步研究的具体近期目标包括：1）分别用hCG/LH和EGF受体cDNA转染大鼠SIG细胞，筛选稳定的转染子SIGC-hCG/LHR和SIGC-EGFR; 2）SIGC-hCG/LHR和SIGC-EGFR的初步表征，其将包括a）通过使用125 IhCG和125 IEGF的结合试验测定hCG/LH和EGF受体的存在和浓度，和B）研究hCG对腺苷酸环化酶和磷脂酶C的激活作用以及EGF对受体酪氨酸激酶的激活作用，3）研究hCG和EGF对Raf、MEK和ERK活性的影响，4）用DNA芯片比较SIGC-hCG/LHR和SIGC-EGFR中hCG和EGF信号转导基因的表达谱; 5）使用特异性多克隆抗体通过缔合或免疫沉淀技术分别测定ERK和Raf激酶的下游和上游信号蛋白;和6）将进行MAP激酶模块的支架蛋白的搜索。