E3 Ubiquitin-Protein Ligase CHIP, Antigen NY-CO-7, CLL-Associated Antigen KW-8, Carboxy Terminus of Hsp70-Interacting Protein, STIP1 Homology and U Box-Containing Protein 1, STUB1, CHIP
E3 Ubiquitin-Protein Ligase CHIP is a cytoplasmic protein. CHIP is highly expressed in skeletal muscle, heart, pancreas, brain and placenta. CHIP interacts with the molecular chaperones Hsc70-Hsp70 and Hsp90 through its TPR domain, lead to in client substrate ubiquitylation and degradation by the proteasome. CHIP targets misfolded chaperone substrates towards proteasomal degradation. CHIP mediates transfer of non-canonical short ubiquitin chains to HSPA8 that have no effect on HSPA8 degradation. CHIP plays a role in base-excision repair: catalyzes polyubiquitination by amplifying the HUWE1/ARF-BP1-dependent monoubiquitination and leading to POLB-degradation by the proteasome. It also may regulate the receptor stability and activity through proteasomal degradation.
