A family of proteins (Bcl-2 associated athanogene products) that act as cochaperones by linking molecules that recruit molecular chaperones to target proteins. BAG-1 (345 aa, three major isoforms p50, p46, and p36 and a minor fourth, p29) facilitates ubiquitin-proteasome-mediated protein degradation. It is antiapoptotic and potentiates the antiapoptotic functions of Bcl-2 to which it binds. It is deregulated in a variety of malignancies. At least four other BAG proteins are known. BAG4 (silencer of death domains, SODD, 457 aa) associates with the TNF receptor 1 (TNFR1) but is displaced if TNF binds. BAG5 (447 aa) inhibits parkin and enhances dopaminergic neuron degeneration.
Subjects: Medicine and Health.