Ras proteins bind GDP/GTP and possess intrinsic GTPase activity (PubMed:20949621). Plays an important role in the regulation of cell proliferation (PubMed:23698361, PubMed:22711838). Plays a role in promoting oncogenic events by inducing transcriptional silencing of tumor suppressor genes (TSGs) in colorectal cancer (CRC) cells in a ZNF304-dependent manner (PubMed:24623306). GTP + H2O = GDP + H(+) + phosphate Alternates between an inactive form bound to GDP and an active form bound to GTP. Activated by a guanine nucleotide-exchange factor (GEF) and inactivated by a GTPase-activating protein (GAP). Interaction with SOS1 promotes exchange of bound GDP by GTP. Interacts with PHLPP. Interacts (active GTP-bound form preferentially) with RGS14 (By similarity). Interacts (when farnesylated) with PDE6D; this promotes dissociation from the cell membrane (PubMed:23698361). Interacts with SOS1 (PubMed:22431598). Interacts (when farnesylated) with GPR31 (PubMed:28619714). Interacts with RAP1GDS1 (PubMed:20709748, PubMed:24415755). Interacts with GPR31; in a farnelysation-dependent manner. Isoforms differ in the C-terminal region which is encoded by two alternative exons (IVA and IVB). Acetylation at Lys-104 prevents interaction with guanine nucleotide exchange factors (GEFs). Palmitoylated at Lys-182, Lys-184 and Lys-185 (PubMed:29239724). Palmitoylation on lysine residues is promoted by palmitoylation at Cys-180 (PubMed:29239724). Lysine-depalmitoylation by SIRT2 promotes its localization to endomembranes in endocytic pathways (PubMed:29239724). Ubiquitinated by the BCR(LZTR1) E3 ubiquitin ligase complex at Lys-170 in a non-degradative manner, leading to inhibit Ras signaling by decreasing Ras association with membranes. (Microbial infection) Glucosylated at Thr-35 by P.sordellii toxin TcsL. The disease is caused by variants affecting the gene represented in this entry. The disease is caused by variants affecting the gene represented in this entry. The disease is caused by variants affecting the gene represented in this entry. The disease is caused by variants affecting the gene represented in this entry. Defects in KRAS are a cause of pylocytic astrocytoma (PA). Pylocytic astrocytomas are neoplasms of the brain and spinal cord derived from glial cells which vary from histologically benign forms to highly anaplastic and malignant tumors. The disease is caused by variants affecting the gene represented in this entry. KRAS mutations are involved in cancer development. The disease is caused by variants affecting the gene represented in this entry. The disease is caused by variants affecting the gene represented in this entry. Belongs to the small GTPase superfamily. Ras family.