a GTPase activator for normal RAS p21 but not its oncogenic counterpart, converting it to the putatively inactive GDP-bound state. Acting as a suppressor of RAS function, it enhances the weak intrinsic GTPase activity of RAS proteins resulting in the inactive GDP-bound form of RAS, thereby allowing control of cellular proliferation and differentiation. Mutations leading to changes in the binding sites of either protein are associated with basal cell carcinomas. Two alternatively spliced isoforms have been described. Note: This description may include information from UniProtKB.
Protein type: GAPs; Motility/polarity/chemotaxis; GAPs, Ras
Biological Process: regulation of cell shape; positive regulation of Ras GTPase activity; embryonic development; regulation of actin filament polymerization; cytokinesis after mitosis; regulation of RNA metabolic process; negative regulation of Ras protein signal transduction; negative regulation of cell adhesion; negative regulation of neuron apoptosis; vasculogenesis; negative regulation of cell-matrix adhesion; signal transduction
SS: The number of records in which this modification site was determined using site-specific methods. SS methods include amino acid sequencing, site-directed mutagenesis, modification site-specific antibodies, specific MS strategies, etc.