P190RhoGAP, also known as GRLF1 (glucocorticoid receptor DNA binding factor 1) is a Rho family GTPase-activating protein that was identified as a protein that associates with p120RasGAP. P190RhoGAP is a multidomain protein that plays crucial role in regulating actin cytoskeletal rearrangements in axonal pathfinding and stability and in response to growth factor stimulation, integrin engagement, and v-Src transformation. Recently, it has been suggested that p190RhoGAP has also a role in regulating cell proliferation.