Premium
The influence of EGF, PM1 mutations and posttranslational processing on the subcellular location of AGS1/DexRas1
Author(s) -
Struckhoff Amanda Parker,
Cismowski Mary J.,
Vaidyanathan Govindan,
Lanier Stephen M.
Publication year - 2006
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.20.5.a1120-a
Subject(s) - subcellular localization , microbiology and biotechnology , cell fractionation , mutant , transfection , organelle , protein subcellular localization prediction , cytosol , biology , wild type , cell , transport protein , cytoplasm , biochemistry , membrane , gene , enzyme
AGS1 (DexRas1, RASD1), a Ras–related protein, was identified as a receptor independent activator of heterotrimeric G‐proteins. As part of a broader effort to define the role of AGS1 in cellular function, we determined the subcellular location of AGS1 and its regulation following expression of AGS1 in COS7 cells. Immunofluorescent imaging of wild type AGS1 or His‐tagged AGS1 transfectants revealed localization to the plasma membrane, consistent with the localization of AGS1 to the 100,000 x g pellet following cell fractionation. Transfected AGS1 is also observed at the perinuclear region, but is not specifically targeted to a defined subcellular organelle. Cellular remodeling observed with EGF treatment (100 ng/ml, 10 minutes) revealed a markedly intense AGS1 immunofluorescent signal at the plasma membrane. The subcellular location of AGS1 is apparently dependent upon both its activation state and posttranslational processing. The putative inactive AGS1 mutant G31V and a C‐terminal CAAX mutant (C278S) were diffusely distributed throughout the cytosol. The putative inactive T38N mutant exhibited a punctuate distribution within the cell that differed from both wild type and the G31V mutant. These data suggest that AGS1is involved in cell signaling events at the plasma membrane and that its subcellular location may be influenced by activation‐dependent interaction with regulatory proteins.