Inhibits the chaperone activity of HSP70/HSC70 by promoting substrate release. Inhibits the pro-apoptotic function of PPP1R15A, and has anti-apoptotic activity. Markedly increases the anti-cell death function of BCL2 induced by various stimuli. Homodimer. Forms a heteromeric complex with HSP70/HSC70. Binds to the ATPase domain of HSP/HSC70 chaperones. Isoform 1, isoform 3 and isoform 4 but not isoform 2 interact with HSPA8/HSC70. Interacts with NR3C1. Interacts with the N-terminal region of STK19. Interacts with PPP1R15A. Interacts with BCL2 in an ATP-dependent manner. Isoform 2 does not interact with BCL2. Up-regulated during differentiation of bladder epithelial cells and down-regulated during differentiation of prostate epithelium. Isoform 4 is the most abundantly expressed isoform. It is ubiquitously expressed throughout most tissues, except the liver, colon, breast and uterine myometrium. Isoform 1 is expressed in the ovary and testis. Isoform 4 is expressed in several types of tumor cell lines, and at consistently high levels in leukemia and lymphoma cell lines. Isoform 1 is expressed in the prostate, breast and leukemia cell lines. Isoform 3 is the least abundant isoform in tumor cell lines. 4 isoforms of the human protein are produced by alternative splicing. Note: This description may include information from UniProtKB.
Protein type: Nuclear receptor co-regulator; Motility/polarity/chemotaxis
SS: The number of records in which this modification site was determined using site-specific methods. SS methods include amino acid sequencing, site-directed mutagenesis, modification site-specific antibodies, specific MS strategies, etc.