GAPVD1 is a 1478 amino acid peripheral membrane protein that acts both as a GTPase-activating protein (GAP) and a guanine nucleotide exchange factor (GEF). GAPVD1 participates in many processes such as insulin receptor internalization, Glut4 trafficking and endocytosis. In addition, depletion of GAPVD1 leads to delayed EGFR degradation by mediating receptor ubiquination through its RGD domain, suggesting that it may be an important mediator of carcinogenesis resulting from Ras protein mutations. There are six isoforms of GAPVD1 that are produced as a result of alternative splicing events.