The proteins have anti-apoptotic activity and increase the anti-cell death function of BCL-2 induced by various stimuli.

BAG-1 promotes cell growth by binding to and stimulating Raf-1 activity.

The binding of Hsp70 to BAG-1 diminishes Raf-1 signalling and inhibits subsequent events, such as DNA synthesis, as well as arrests the cell cycle.

BAG-1 has been suggested to function as a molecular switch that encourages cells to proliferate in normal conditions but become quiescent under a stressful environment .

The BAG domain is evolutionarily conserved, and BAG domain containing proteins have been described and/or proven in a variety of organisms including Mus musculus (Mouse), Xenopus spp., Drosophila spp., Bombyx mori (Silk moth), Caenorhabditis elegans, Saccharomyces cerevisiae (Baker's yeast), Schizosaccharomyces pombe (Fission yeast), and Arabidopsis thaliana (Mouse-ear cress).