Rho GDP Dissociation Inhibitor Gamma (ARHGDIg)

The sequence of the predicted 225-amino acid protein is approximately 50% identical to those of RhoGDI and GDI/D4, and contains a hydrophobic amino terminus not seen in the other proteins. In vitro, RhoGDI-gamma functioned as a GDI for CDC42 , but with 20 times less efficiency than RhoGDI.Using immunofluorescence of mammalian cells expressing RhoGDI-gamma, Adra et al. (1997) found that the protein is distributed in a diffuse punctate pattern in the cytoplasm and concentrated in vesicles in the perinuclear area. Overexpression caused the cells to """round up,""" with loss of stress fibers. Northern blot analysis revealed that RhoGDI-gamma is expressed as 2.5- and 4.5-kb transcripts primarily in pancreas and brain.