PLASMA MEMBRANE REGIONS OF CELLS GROWN AS MONOLAYERS

单层生长细胞的质膜区域

基本信息

批准号：
6656724
负责人：
BRUCE Shell JACOBSON
金额：
$ 4.24万
依托单位：
UNIVERSITY OF MASSACHUSETTS AMHERST
依托单位国家：
美国
项目类别：
财政年份：
1981
资助国家：
美国
起止时间：
1981-04-01 至 2004-06-30
项目状态：
已结题

项目摘要

Adhesion of cells to an extracellular matrix (ECM) is involved in a number of biological phenomena including wound healing, embryogenesis, blood coagulation, and metastasis. The long term goal of this project is to elucidate the molecular events that commence with the cell attachment stage of cell-substrate adhesion and regulate the ensuing cell spreading and cell migration stages. We have demonstrated that during attachment of cells to collagen of fibronectin the cognate receptors become clustered and activate cytosolic phospholipase A2 by phosphorylation and translocation to the membrane where arachidonic acid (AA) is release from phospholipids. AA can be oxidized by lipoxygenase into metabolites that turn on the production of diacylglycerol followed by the translocation of protein kinase C to the membrane to activate actin polymerization and the cell spreading stage of adhesion. This information and preliminary work leads to the following hypothesis: Cell spreading and cell migration are regulated respectively by two lipid second messenger pathways which are branches of AA metabolism; lipoxygenase (LOX) and cyclooxygenase (COX) metabolites separately activate sequences of kinases and small GTP-binding proteins leading respectively to the polymerization of actin essential for spreading and bundling of actin filaments essential for migration. Pharmacological, biochemical and molecular biological strategies will be used to evaluate the hypothesis by exploring the following specific aims: 1. Determine which COX metabolites upregulate cAMP to increase PKA activity for actin bundling and migration. 2. Determine whether the amount of COX that is ectopically expressed or expressed in response to a calcium signal determines the level of cAMP and the rate of migration. 3. Establish if and where the GTP-binding proteins, Cdc42, Rac and Rho are involved in the LOX and COX pathways. 4. Ascertain how the metabolites of the three lipoxygenases might regulate the production of diacylglycerol which is essential for PKC activation in the cell spreading stage of adhesion.

细胞对细胞外基质（ECM）的粘附参与A 生物学现象的数量，包括伤口愈合，胚胎发生，血液凝血和转移。这个项目的长期目标是为了阐明从细胞开始的分子事件细胞基底粘附的附着阶段并调节随后的细胞扩散和细胞迁移阶段。我们已经证明了在连接到纤连蛋白胶原蛋白的胶原蛋白的胶原蛋白受体聚集并激活胞质磷脂酶A2 磷酸化和易位到膜酸中酸的膜（AA）从磷脂中释放。 AA可以用脂氧合酶氧化进入二酰基甘油的产生的代谢产物通过将蛋白激酶C的易位到膜上激活肌动蛋白聚合和粘附的细胞扩散阶段。这信息和初步工作导致以下假设：细胞扩散和细胞迁移分别由两个脂质调节第二通道途径是AA代谢的分支；脂氧合酶（LOX）和环氧合酶（COX）代谢物分别激活激酶的序列和小的GTP结合蛋白领先分别与肌动蛋白的聚合进行分散和扩散至关重要肌动蛋白丝捆绑对于迁移必不可少的。药理学，生化和分子生物学策略将用于评估通过探索以下特定目的来假设：1。哪种COX代谢物上调营地以增加肌动蛋白的PKA活性捆绑和迁移。 2。确定Cox的数量是否响应钙信号的异位表达或表达确定营地的水平和迁移率。 3。建立如果以及GTP结合蛋白的位置，cdc42，rac和rho涉及在Lox和Cox途径中。 4。确定如何三氧合酶可能调节二酰基甘油的产生这对于在细胞扩散阶段的PKC激活至关重要粘附。