Intersectin 1 (SH3 domain protein); Acts as guanine nucleotide exchange factor (GEF) specific for the CDC42 GTPase (By similarity). Adapter protein that may provide indirect link between the endocytic membrane traffic and the actin assembly machinery. May regulate the formation of clathrin-coated vesicles. Involved in endocytosis of integrin beta-1 (ITGB1) and transferrin receptor (TFR); internalization of ITGB1 as DAB2-dependent cargo but not TFR may involve association with DAB2. Isoform 1 could be involved in brain-specific synaptic vesicle recycling. Inhibits ARHGAP31 activity toward RAC1; C2 domain containing
Synonyms: ITSN1, ITSN1p, hITSN1, A7XZY7, A8CTZ0 ...