ASSOCIATION OF THE RAS-ANTAGONISTIC RAP1/KREV-1 PROTEINS WITH THE GOLGI-COMPLEX
ASSOCIATION OF THE RAS-ANTAGONISTIC RAP1/KREV-1 PROTEINS WITH THE GOLGI-COMPLEX
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DOI：
10.1073/pnas.88.5.1606
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发表时间：
1991-03-01
影响因子：
11.1
通讯作者：
DEGUNZBURG, J
中科院分区：
文献类型：
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作者：
BERANGER, F;GOUD, B;DEGUNZBURG, J
RAS癌基因编码21 kDa的GTP结合蛋白，能够在培养中转化永生化细胞。RAS蛋白通过其C末端结合到质膜的内面，并被认为通过跨越氨基酸32-42的“效应”区域传递其有丝分裂信号。两个与ras相关的人类基因Rap1A和Rap1B编码95%的同源21 kDa蛋白，它们与ras p21具有相同的效应结构域和相似的C-末端Cys-ALI-ALI-Xaa序列(其中ALI是一种脂肪族氨基酸，也称为CAAX序列)。该基因的产物与Krev-1基因的产物相同，其过表达能够逆转Ki-ras转化的NIH3T3细胞的表型。通过用包含Rap1蛋白121-137残基的多肽免疫兔子，获得了与RAS和其他RAS相关蛋白不发生交叉反应的抗体。这些抗体被用来通过间接免疫荧光和分级技术研究Rap1蛋白的亚细胞定位。RAP1蛋白被发现与细胞膜紧密结合。它们不与质膜上的RAS蛋白共定位，并被发现与高尔基复合体有关。
Ras oncogenes encode 21-kDa GTP-binding proteins that are capable of transforming immortalized cells in culture. Ras proteins are bound to the inner face of the plasma membrane by their C-terminal extremity and are thought to transmit their mitogenic signals via an "effector" domain spanning amino acids 32-42. Two ras-related human genes rap1A and rap1B encode 95% homologous 21-kDa proteins that share with Ras p21 the same effector domain and a similar C-terminal Cys-Ali-Ali-Xaa sequence (where Ali is an aliphatic amino acid; also known as a CAAX sequence). The product of the rap1A gene is identical to that of the Krev-1 cDNA, whose overexpression is capable of reverting the phenotype of Ki-ras-transformed NIH 3T3 cells. Antibodies that do not cross-react with Ras and other Ras-related proteins were obtained by immunizing rabbits with a peptide encompassing residues 121-137 of Rap1 proteins. These antibodies were used to investigate the subcellular localization of Rap1 proteins by indirect immunofluorescence and fractionation techniques. Rap1 proteins were found to be tightly bound to cellular membranes. They did not colocalize with Ras proteins on the plasma membrane and were discovered to be associated with the Golgi complex.