SH3BP1
Description
The SH3BP1 (SH3 domain binding protein 1) is a protein-coding gene located on chromosome 22.
SH3 domain-binding protein 1 is a protein that in humans is encoded by the SH3BP1 gene.
SH3BP1 acts as a GTPase activating protein (GAP) that specifically converts active, GTP-bound Rho-type GTPases (RAC1 and CDC42) into their inactive, GDP-bound form. This inactivation of RAC1 at the leading edge of migrating cells regulates the organization of cell protrusions, crucial for proper cell migration. SH3BP1 also negatively regulates CDC42 during actin remodeling and the formation of epithelial cell junctions. Its GAP activity towards RAC1 and/or CDC42 is essential for phagocytosis of large particles, where it's recruited to sites of particle engagement by PI3 kinase (PI3K) and inactivates RAC1/CDC42 to reorganize the actin cytoskeleton for engulfment. SH3BP1 also participates in angiogenesis and repulsive guidance within the semaphorin-plexin signaling pathway. Following PLXND1 binding to extracellular SEMA3E, SH3BP1 dissociates from PLXND1 and inactivates RAC1, causing actin cytoskeleton reorganization and cell collapse.
SH3BP1 is also known as ARHGAP43.
