BAG3 protein, also known as Bcl2-associated athanogene 3, is a 575 amino acid multi-functional protein that is widely expressed across various tissues but is most abundant in cardiac muscle, skeletal muscle, the brain, and many cancers. It plays a crucial role in maintaining cellular homeostasis by supporting the autophagy of misfolded proteins and damaged organelles, inhibiting apoptosis, preserving mitochondrial homeostasis, and facilitating excitation-contraction coupling through the L-type calcium channel and the beta-adrenergic receptor. High levels of BAG3 are associated with resistance to chemotherapy in malignant cells, while both loss of function and gain of function variants are linked to cardiomyopathy. BAG3 is also characterized by its multiple protein-protein binding domains, which enable it to establish discrete intracellular micro-environments based on its specific responsibilities and locations within the cell. .