Ceramide synthase that catalyzes the transfer of the acyl chain from acyl-CoA to a sphingoid base, with high selectivity toward very-long-chain fatty acyl-CoA (chain length C22-C27) (PubMed:17977534, PubMed:18165233, PubMed:18541923, PubMed:19728861, PubMed:20937905, PubMed:22144673, PubMed:22661289, PubMed:26887952, PubMed:29632068). N-acylates sphinganine and sphingosine bases to form dihydroceramides and ceramides in de novo synthesis and salvage pathways, respectively (By similarity) (PubMed:17977534, PubMed:18165233, PubMed:18541923, PubMed:19728861, PubMed:20937905, PubMed:22144673, PubMed:22661289, PubMed:26887952, PubMed:29632068). Plays a non-redundant role in the synthesis of ceramides with very-long-chain fatty acids in kidney, liver and brain. Regulates the abundance of myelin-specific sphingolipids galactosylceramide and sulfatide that affects myelin sheath architecture and motor neuron functions (By similarity).