Co-chaperone that regulates diverse cellular pathways, such as programmed cell death and stress responses (PubMed:16003391). Involved in plant basal resistance (PubMed:16636050, PubMed:26739014). Involved in basal heat response through the regulation of the heat induced small HSP (sHSP) transcriptional cascade (PubMed:26580143). Induces autophagy. Binds to the ATPase domain of HSP70/HSC70 chaperones (By similarity). Interacts with calmodulins CAM1, CAM2, CAM3, CAM4, CAM6 and CAM7 (PubMed:16003391). Interacts with BAGP1 and APCB1 (PubMed:26739014). Detected in stems, leaves, flowers and roots. By heat shock, by salicylic acid (SA), by abscisic acid (ABA), by calcium, by hydrogen peroxide, and by pathogen B.cinerea attack. Up-regulated by HSFA2. IQ domain mediates interaction with calmodulin. Early flowering and shorter vegetative and reproductive phases, with more branched roots and inflorescences (PubMed:16636050). Early senescence (PubMed:16636050). Hypersensitivity to light (PubMed:16636050). Enhanced susceptibility to B.cinerea and permissive fungal growth (PubMed:16636050, PubMed:26739014). Overexpression of BAG6 results in a lesion mimic phenotype. Processed by APCB1 during lesion mimic development. The cleavage is triggered by pathogen infection or by pathogen-associated molecular patterns (PAMPs).