Endoplasmic reticulum palmitoyl acyltransferase that mediates palmitoylation of proteins such as AMFR, CALX, ITPR1 and TFRC (PubMed:25368151). Palmitoylates calnexin (CALX), which is required for its association with the ribosome-translocon complex and efficient folding of glycosylated proteins (By similarity). Mediates palmitoylation of AMFR, promoting AMFR distribution to the peripheral endoplasmic reticulum (By similarity). Together with SELENOK, palmitoylates ITPR1 in immune cells, leading to regulate ITPR1 stability and function (PubMed:25368151). Stearoyltransferase that mediates stearoylation of TFRC to inhibit TFRC-mediated activation of the JNK pathway and mitochondrial fragmentation (By similarity). hexadecanoyl-CoA + L-cysteinyl-[protein] = CoA + S-hexadecanoyl-L-cysteinyl-[protein] L-cysteinyl-[protein] + octadecanoyl-CoA = CoA + S-octadecanoyl-L-cysteinyl-[protein] Homooligomerizes (By similarity). Interacts with SELENOK (PubMed:25368151). When not palmitoylated, accumulates to dot-like structures in the endoplasmic reticulum. Experimental confirmation may be lacking for some isoforms. The DHHC domain is required for palmitoyltransferase activity. The C-terminal di-lysine motif confers endoplasmic reticulum localization. Palmitoylated at 3 different sites by ZDHHC16. The combination of the different palmitoylation events strongly affects the quaternary assembly of ZDHHC6, its localization, stability and function. Palmitoylation at Cys-328 accelerates the turnover of ZDHHC6. Depalmitoylated by LYPLA2. Belongs to the DHHC palmitoyltransferase family.