ISOLATION OF GP330/MEGALIN INTERACTING PROTEINS

GP330/MEGALIN 相互作用蛋白的分离

• 批准号: 2774719
• 负责人: KEVIN M PATRIE
• 金额: $ 3.67万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-07-01 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/2774719
• 关键词: binding proteins; chimeric proteins; complementary DNA; epithelium; glycoproteins; immunoprecipitation; kidney; laboratory mouse; laboratory rat; membrane proteins; molecular cloning; molecular site; northern blottings; protein localization; protein protein interaction; protein structure function; receptor; western blottings

We have recently isolated a partial cDNA encoding a protein which binds to the carboxy-terminal tail of a membrane receptor known as gp330/megalin. gp330 is a large glycoprotein receptor that has been shown to be the antigen involved in Heymann nephritis, a rat model of human membranous glomerulonephritis. The expression of gp330 is only expressed on the apical surface of epithelial cells such as the kidney proximal tubule brush border. The truncated protein which we have isolated contains a recently identified protein interaction domain known as the PDZ domain. This domain has been shown to bind to an amino acid sequence motif found at the extreme carboxy-terminus of cell surface receptors. gp330 contains such a motif and it is believed that the truncated protein, which we have named GASP, may be a physiological binding partner to gp330. Most proteins containing PDZ domains function in localizing receptor and channel proteins to distinct areas of a cell such as neuronal synapses and cell-to-cell contacts. We will be cloning the full length GASP cDNA in an attempt to learn more about the proteins function through the identification of other protein interacting domains. In addition, we will be characterizing the interaction of GASP with gp330 at the molecular level in an attempt to provide evidence that GASP is involved in the localization and function of gp330 within the kidney epithelia.

我们最近分离出一个部分cDNA编码的蛋白质， 连接到膜受体的羧基末端， gp330/megalin。 gp 330是一种大的糖蛋白受体， 表明是涉及Heymann肾炎的抗原，Heymann肾炎是一种大鼠模型， 人膜性肾小球肾炎 gp 330的表达仅为 在上皮细胞如肾脏的顶端表面表达 近端小管刷状缘。 截短的蛋白质 分离的包含最近鉴定的已知的蛋白质相互作用结构域 作为PDZ域。该结构域已被证明与氨基酸结合 在细胞表面羧基末端发现的序列基序 受体。 gp 330含有这样的基序，并且据信， 截短的蛋白质，我们命名为GASP，可能是一种生理上的 GP 330的结合伴侣。 大多数含有PDZ结构域的蛋白质 在将受体和通道蛋白定位到细胞的不同区域中， 例如神经元突触和细胞与细胞的接触。 我们将克隆 GASP全长cDNA，试图了解更多的蛋白质 通过识别其他蛋白质相互作用 域. 此外，我们将描述GASP的相互作用 在分子水平上与gp 330进行比较， GASP参与了gp 330在细胞内的定位和功能。 肾上皮