Acts as a general chaperone in regulated exocytosis (PubMed:9395474). Acts as a co-chaperone for the SNARE protein SNAP-25 (By similarity). Involved in the calcium-mediated control of a late stage of exocytosis (By similarity). May have an important role in presynaptic function. May be involved in calcium-dependent neurotransmitter release at nerve endings (By similarity). Homodimer (By similarity). Interacts with the chaperone complex consisting of HSC70 and SGTA (By similarity). Interacts with ZDHHC13 (via ANK repeats) (PubMed:26198635). Interacts with ZDHHC17 (via ANK repeats) (PubMed:26198635). Interacts with HSC70 (PubMed:9395474). Interacts with SYT1, SYT5 and SYT7, and with SYT9, forming a complex with SNAP25 (By similarity). The association with membranes is regulated by palmitoylation. Ser-10 phosphorylation induces an order-to-disorder transition triggering the interaction with Lys-58 (By similarity). This conformational switch modulates DNAJC5's cellular functions by reducing binding to syntaxin and synaptogamin without altering HSC70 interactions (By similarity). Palmitoylated (PubMed:18596047). Could be palmitoylated by DHHC3, DHHC7, DHHC15 and DHHC17 (PubMed:18596047). Palmitoylation occurs probably in the cysteine-rich domain and regulates DNAJC5 membrane attachment (PubMed:18596047).