| Primary Identifier | IPR030555 | Type | Family |
| Short Name | HIP1R |
| description | Huntingtin-interacting protein 1-related protein (HIP1R, also known as HIP-12) belongs to the Sla2 family. HIP1R is the only known mammalian relative of huntingtin-interacting protein 1 (HIP1) []. HIP1R may have a role in actin regulation during endocytosis and is shown to promote clathrin assembly. It may also be involved in the apoptotic pathway through its interaction with a member of the Bcl-2 pro-apoptotic family [].The Sla2 family, also known as Sla2p/HIP1/HIP1R family, including Sla2p from budding yeasts [], End4 from fission yeasts [], Huntingtin-interacting protein 1 (HIP1) and HIP1-related (HIP1R) from humans and mice []. They are adaptor proteins that link actin to clathrin and endocytosis in the clathrin-mediated endocytosis (CME) pathway. They contain the ENTH and ANTH (E/ANTH) domain that binds both inositol phospholipids and proteins that contribute to the nucleation and formation of clathrin coats on membranes []. They also contain an I/LWEQ (talin-like) domain, which is an actin-binding domain found in proteins that serve as linkers between the actin cytoskeleton and cellular compartments []. The talin-like domains of Sla2p and HIP1R have been shown to bind F-actin (filamentous actin), however, the same level of actin binding has not been observed with HIP1 []. The central domain of the Sla2p/HIP1/HIP1R proteins contains a coiled-coil domain and several consensus sequences enabling protein-protein interactions []. Yeast Sla2p has been extensively studied: Sla2p arrives at existing endocytic patches with a ~25 seconds delay relative to clathrin and dissociates simultaneously with clathrin upon recruitment of actin-related proteins [, ]. It serves as a bridge, connecting the endocytic patch to the cortical actin cytoskeleton []. |
