LACTOGEN-REGULATED CALPACTIN GENE

催乳素(PRL)及相关激素在婴幼儿的父母照料中起着重要作用 后代和新陈代谢的调节。在哺乳动物中，这包括 妊娠和哺乳的调节。催乳素不仅控制 乳源性乳腺分化，也影响多种 其他靶组织。这些影响中的许多对于支持 与妊娠相关的生长、分化和营养 养育。 这项研究计划的总体目标是了解分子 从钙调蛋白的刺激研究催乳素作用的生理学 在鸽类作物中的表达。这种监管效果是一种富有成效的模式 一种同时检查两种分子机制的系统 催乳素诱导的基因表达及编码钙离子的基因功能 依赖的膜结合蛋白，是主要的细胞底物 癌基因和生长因子受体酪氨酸激酶。 我们将要检测的PRL调节基因(Calpactin)是天生的 作为基础细胞生物学的一个组成部分，以及作为一个 研究PRL机制的有价值的终点。这是一个积极的方面 这一制度有别于其他受PRL监管的制度(即 乳蛋白基因)不起任何基础或一般作用 细胞生理学。 这些实验的目的集中在三个一般主题上。第一 我们已有的催乳素诱导的钙化肌动蛋白基因的综合分析 克隆的。这些实验将确定独特的结构 与这种形式的钙调蛋白基因的诱导有关。假设 测试将包括PRL诱导的calpactin基因被拼接到 一种特定的方式，或者它是从另一种启动子中表达的 地点。不受PRL调控的相关mRNAs将与 确定该基因表达的特殊特征。第二, 人钙调蛋白片段的重组，这些片段是 酪氨酸激酶对催乳素诱导的酪氨酸激酶的调节作用 将制造和测试酪氨酸激酶调节的钙化蛋白。 这些实验将检验这样一种假设，即生产性磷酸化 调节是由下游的特定氨基酸序列决定的 人钙化肌动蛋白的磷酸化位点。第三，免疫定位 对Calpactin蛋白表达的影响及对Calpactin mRNA表达的中和作用 将使用反义寡核苷酸来检测这一功能 蛋白质在PRL诱导的增殖分化中的作用。

Prolactin (PRL) and related hormones play major roles in parental care of offspring and the regulation of metabolism. In mammals this includes regulation of pregnancy and lactation. Prolactin not only controls the lactogenic differentiation of mammary gland, but also affects a variety of other target tissues. Many of those effects are important to support the growth, differentiation, and nutrition associated with pregnancy and nurturing. The general goal of this research program is understanding the molecular physiology of PRL action by studying the stimulation of calpactin expression in pigeon cropsac. This regulatory effect is a productive model system in which to examine simultaneously both the molecular mechanisms of PRL-induced gene expression and the function of genes which encode Ca2+- dependent membrane-binding proteins that are major cellular substrates of oncogene and growth-factor receptor tyrosine kinases. The PRL-regulated gene which we will be examining (calpactin) is inherently interesting as a component of basic cellular biology, as well as being a valuable endpoint from which to study PRL mechanisms. This is one positive aspect which distinguishes this system from others regulated by PRL (i.e. milk protein genes) which do not play any fundamental or general roles in cellular physiology. The aims of these experiments are focussed on three general topics. First a comprehensive analysis of the PRL-induced calpactin gene which we have cloned. These experiments will determine the unique structures which are associated with induction of this form of the calpactin genes. Hypotheses to be tested will include that the PRL-induced calpactin gene is spliced in a specific manner or that it is expressed from an alternative promoter site. Related mRNAs which are not PRL-regulated will be compared to determine special features of this gene's expression. Second, recombinations of segments of a human calpactin which are sites of regulation by tyrosine kinases with equivalent segments of the PRL-induced calpactin which is to tyrosine kinase-regulated will be made and tested. These experiments will test the hypothesis that productive phosphorylative regulation is determined by specific amino acid sequences downstream from the phosphorylation site in human calpactin. Thirdly, immunolocalization of calpactin protein and neutralization of calpactin mRNA expression with antisense oligonucleotides will be used to examine the function of this protein in PRL-induced proliferation and differentiation.