Dexamethasone Induced Ras Related Protein 1 (RASD1)

RASD1 encodes a Ras-related protein that is stimulated by dexamethasone. The exact function of this gene is unknown, but it may play a role in dexamethasone-induced alterations in cell morphology, growth and cell-extracellular matrix interactions. In addition, studies of a similar rat protein suggest that it functions as as a novel physiologic nitric oxide (NO) effector. The gene product belongs to the Ras superfamily of small GTPases. The deduced 281-amino acid protein, which is 98% identical to the mouse protein, contains a P loop, guanine base-binding loops, and a C-terminal farnesylation site. SDS-PAGE analysis detected a 33-kD protein, close to the predicted size. Northern blot analysis revealed ubiquitous expression of a 5.0-kb RASD1 transcript, with highest levels in heart. Dexamethasone exposure upregulated RASD1 expression.