ITSN1
Description
The ITSN1 (intersectin 1) is a protein-coding gene located on chromosome 21.
Intersectin-1 is a protein that, in humans, is encoded by the ITSN1 gene. The protein encoded by this gene is a cytoplasmic membrane-associated protein that indirectly coordinates endocytic membrane traffic with the actin assembly machinery. In addition, the encoded protein may regulate the formation of clathrin-coated vesicles and could be involved in synaptic vesicle recycling. This protein has been shown to interact with dynamin, CDC42, SNAP23, SNAP25, SPIN90, EPS15, EPN1, EPN2, and STN2. Multiple transcript variants encoding different isoforms have been found for this gene, but the full-length nature of only two of them have been characterized so far.
Intersectin-1 is an adapter protein that links endocytic membrane traffic with the actin assembly machinery. It acts as a guanine nucleotide exchange factor (GEF) for CDC42, stimulating actin nucleation via WASL and the ARP2/3 complex. Intersectin-1 is involved in the assembly and maturation of clathrin-coated vesicles, recruiting FCHSD2 to these pits. It plays a role in endocytosis of activated EGFR and other growth factor receptors, as well as integrin beta-1 (ITGB1) and transferrin receptor (TFR). Intersectin-1 promotes EGFR ubiquitination and degradation, downregulating EGFR signaling. It is required for normal exocytosis of catecholamines in chromaffin cells and for rapid replenishment of synaptic vesicles at presynaptic active zones. Intersectin-1 inhibits ARHGAP31 activity towards RAC1.
ITSN1 is also known as ITSN, SH3D1A, SH3P17.
