Co-chaperone for HSPA8/Hsc70 . Stimulates ATP hydrolysis, but not the folding of unfolded proteins mediated by HSPA1A (in vitro) . Plays a role in protein transport into mitochondria via its role as co-chaperone. Functions as a co-chaperone for HSPA1B and negatively regulates the translocation of BAX from the cytosol to mitochondria in response to cellular stress, thereby protecting cells against apoptosis . Promotes apoptosis in response to cellular stress mediated by exposure to anisomycin or UV .
Subcellular locations: Membrane, Cytoplasm, Microsome, Nucleus, Cytoplasm, Perinuclear region, Mitochondrion
Primarily associated with microsomes. A minor proportion is associated with mitochondria (By similarity). Primarily cytoplasmic. A minor proportion is associated with nuclei.
Ubiquitous. Isoform 2 is highly expressed in testis and lung, but detected at low levels in thymus, prostate, colon and liver.