Overview:

CHIP(STUB1) or STIP1 homology and U-box containing protein 1 (also known as E3 ubiquitin protein ligase) is a ubiquitin ligase/cochaperone that participates in protein quality control by targeting a broad range of chaperone protein substrates for degradation (1). CHIP acts as a molecular switch for the degradation of misfolded proteins via the proteasome and lysosome pathways (2). CHIP controls the cellular level of BER enzymes and, correspondingly, the efficiency and capacity of BER. CHIP E3 ubiquitin ligases act sequentially in ER membrane and cytosol to monitor the folding status of CFTR and delF508.CHIP possesses intrinsic E3 ubiquitin ligase activity and promotes ubiquitylation.

Gene Aliases:

CHIP; UBOX1; HSPABP2; NY-CO-7; SDCCAG7

Genbank Number:

NM_005861

References:

1. Min, J.-N. et.al: CHIP deficiency decreases longevity, with accelerated aging phenotypes accompanied by altered protein quality control. Molec. Cell. Biol. 28: 4018-4025, 2008.

2. Shin, Y.et.al: The co-chaperone carboxyl terminus of Hsp70-interacting protein (CHIP) mediates alpha-synuclein degradation decisions between proteasomal and lysosomal pathways. J. Biol. Chem. 280: 23727-23734, 2005.