HYPK

HYPK, short for Huntingtin Yeast-two-Hybrid Protein K, is a human protein encoded by the HYPK gene. It was identified in a yeast two-hybrid screen as an interactor of huntingtin, the product of the HTT gene. Biochemically, HYPK functions as a co-chaperone of the HSP70 chaperone system, interacting with members of the HSP70 family to influence protein folding and cellular proteostasis.

HYPK is expressed in a range of human tissues, and its subcellular localization has been described primarily in the cytosol, with occasional reports of nuclear distribution under certain cellular conditions. As a co-chaperone, HYPK modulates HSP70 activity and can affect the handling of misfolded proteins, including pathological forms of huntingtin that contain expanded polyglutamine tracts in cellular models.

In research contexts, HYPK has been studied for its potential involvement in Huntington’s disease and broader protein quality control as a modulator of polyglutamine aggregation. However, there is no consensus on a defined physiological role or disease mechanism, and the therapeutic significance of HYPK remains under investigation.

HYPK is part of the broader HSP70 co-chaperone network, contributing to the regulation of chaperone-mediated protein folding and quality control through its interactions with chaperone components.