Signal Induced Proliferation Associated 1 Like Protein 3 (SIPA1L3)

SIPA1L3 is a member of the SIPA1 family of RapGAPs. SIPA1L3 was cloned as a novel molecular component of tight junctions and adherens junctions, suggesting that may function to balance Rap1 by counteracting RapGEFs). Recent studies of SIPA indicate that its deregulation can cause myeloproliferative stem cell disorders in mice and increased metastases in human cancers. Other studies suggest SIPA1L1 may play important roles in embryo development and control of cell proliferation. Based on the amount of homology between SIPA family members, it is possible that SIPA1L3 plays other roles development and cell proliferation. SIPA1 is a mitogen induced GTPase activating protein (GAP). It exhibits a specific GAP activity for Ras-related regulatory proteins Rap1 and Rap2, but not for Ran or other small GTPases.