GASTRIN-RELEASING PEPTIDE GENE EXPRESSION

蛙黄素一种哺乳动物，相当于两栖动物多肽蛙皮素，命名为 胃泌素释放肽(GRP)具有强大的生物学效应，包括 释放几种肠肽激素，与神经调节相一致 角色。GRP还能诱导细胞增殖，提示它在生长中起作用。 监管。在哺乳动物的大脑、肠道、胎肺和 神经内分泌肿瘤。人类GRP的三个mRNAs(S)已经被 从人肺NE肿瘤中分离出来，所有这些基因都编码GRP，但不同 在ProGRP的C-末端延伸肽中，由于有19或21个碱基 插入/删除剪接事件。这个项目的主要目标是 测定大鼠基因的序列和发育性表达 编码GRP。这将使组织特异性GRP基因的分析成为可能 在大鼠胚胎发育中的表达，这应该能阐明GRP在正常胚胎发育中的作用 哺乳动物的生长发育以及肿瘤的发生。初步研究 在人类胚胎肺发育过程中表现出免疫活性GRP的峰值 在妊娠18至24周的NE细胞中，其mRNA水平达到峰值 16~22周，与肺小管期相关 成长。我的具体目标是：(1)完成大鼠GRP的测序 基因，以阐明可能的RNA剪接变异体的确切结构。 (2)正常大鼠组织特异性基因表达谱分析 胚胎发生：通过RNA印迹和S1定位，在整个组织匀浆中， 并在胚胎组织切片中通过原位杂交精确地 定位细胞特异性GRP mRNA。将获得大鼠GRP和ProGRP(S)抗血清 提出并用于免疫过氧化物酶研究，以与原位相关 连续胚胎切片上的杂交。重要的是要确定 是否也表达了C末端的多肽，就像这些可能 生物功能。GRP免疫电子显微镜与GRP受体 将进行类似的放射自显影，以进一步澄清GRP 生理作用。(3)确定GRP参与病理过程。 原位杂交和免疫组织化学分析 GRP和C端肽。主要焦点将放在肺肿瘤上， 其中GRP被认为是一种潜在的内分泌生长因子。 因此，Grp基因(S)可能在发育中的组织中瞬时表达为 细胞分化中程序性基因调控的一部分，以及 对这种表达的分析可能会阐明基因解除调控的机制。 在肿瘤形成方面。

A mammalian equivalent of the amphibian peptide bombesin, designated gastrin-releasing peptide (GRP), has potent biological effects, including release of several gut peptide hormones, consistent with a neuroregulatory role. GRP also induces cell proliferation, suggesting a role in growth regulation. GRP has been found in mammalian brain, gut, fetal lung, and neuroendocrine (NE) tumors. Three mRNAs for human GRP(s) have been isolated from human pulmonary NE tumors, all of which encode GRP but differ in the C-terminal extension peptide of proGRP, due to a 19 or 21 base insertion/deletion splicing event. The major objective of this project is to determine the sequence and developmental expression of the rat gene encoding GRP. This will allow analyses of tissue-specific GRP gene expression in rat embryogenesis, which should clarify GRP's role in normal mammalian growth and development, as well as in neoplasia. Initial studies of human fetal lung development have demonstrated peak immunoreactive GRP in NE cells at 18 to 24 weeks of gestation, which follows peak mRNA levels at 16 to 22 weeks and correlates with the canalicular period of lung growth. My specific aims are: (1) to complete sequencing of the rat GRP gene, to clarify the exact structure of possible RNA splicing variants. (2) To analyze patterns of tissue-specific gene levels in normal rat embryogenesis: in whole tissue homogenates by RNA blotting and S1 mapping, and in embryo tissue sections by in situ hybridization to precisely localize cell-specific GRP mRNA. Antisera to rat GRP and proGRP(s) will be raised and used for immunoperoxidase studies to be correlated with in situ hybridization on serial embryo sections. It will be important to determine whether C-terminal peptides are also expressed, as these may have biological functions. GRP-immunoelectron microscopy and GRP receptor autoradiography will be similarly carried out to further clarify GRP's physiological role. (3) to determine GRP's involvement in pathological processes by in situ hybridization and immunohistochemical analyses for both GRP and C-terminal peptides. The major focus will be on lung tumors, where GRP has been implicated as a potential atuocrine growth factor. Thus, GRP gene(s) may be transiently expressed in developing tissues as part of programmed gene regulation in cellular differentiation, and analyses of this expression may elucidate mechanisms of gene deregulation in oncogenesis.