Huntingtin-interacting protein 1-related protein (HIP1R)

Huntingtin-interacting protein 1-related protein (HIP1R) is an endocytic adaptor protein that belongs to the Sla2/HIP1 family, characterized by domains for binding clathrin, inositol lipids, and F-actin[1][7]. HIP1R contains an AP180 N-terminal homology (ANTH) domain, a central coiled-coil region for clathrin light-chain binding, and a C-terminal THATCH domain for F-actin linkage[7]. It is ubiquitously expressed, especially in the brain, and is localized to clathrin-coated pits and vesicular structures, where it coordinates membrane trafficking and cytoskeletal dynamics during endocytosis[6][2]. HIP1R plays an important role in neural development, dendritic branching, and excitatory synapse formation; knockdown in primary neurons selectively impairs dendrite growth, glutamate receptor expression, and excitatory transmission[1][7]. Mechanistically, HIP1R stabilizes receptor tyrosine kinases such as EGFR after ligand-induced endocytosis and supports survival signaling[6][7]. Although HIP1R is structurally related to huntingtin-interacting protein 1 and does not interact directly with huntingtin or have a defined role in Huntington’s disease, genetic studies highlight its importance in neurobiology and other developmental processes[1][2][4]. No drugs currently target HIP1R directly, and no known clinical biomarkers or safety data exist for therapeutic manipulation of this protein.

Other names

HIP1RHIP12KIAA0655HIP1-related proteinHIP-12HIP3FLJ14000ILWEQHuntingtin-interacting protein 12huntingtin-interacting protein 1-related protein

Not therapeutically targeted; mechanistically, HIP1R regulates endocytosis, stabilizes receptor tyrosine kinases (e.g., EGFR) following ligand-induced endocytosis[7], links actin cytoskeleton to clathrin-coated vesicle formation[6][3]