Open AccessCeramide turnover in GtoPdb v.2021.3
Author(s) -
Anthony H. Futerman
Publication year - 2021
Publication title -
iuphar/bps guide to pharmacology cite
Language(s) - English
Resource type - Journals
ISSN - 2633-1020
DOI - 10.2218/gtopdb/f767/2021.3
Subject(s) - ceramide , sphingomyelin , endoplasmic reticulum , sphingosine , sphingolipid , golgi apparatus , ceramide synthase , lipid signaling , microbiology and biotechnology , chemistry , biochemistry , phosphorylation , biology , enzyme , apoptosis , membrane , receptor
Ceramides are a family of sphingophospholipids synthesized in the endoplasmic reticulum, which mediate cell stress responses, including apoptosis, autophagy and senescence, Serine palmitoyltransferase generates 3-ketosphinganine, which is reduced to dihydrosphingosine. N-Acylation allows the formation of dihydroceramides, which are subsequently reduced to form ceramides. Once synthesized, ceramides are trafficked from the ER to the Golgi bound to the ceramide transfer protein, CERT (COL4A3BP, Q9Y5P4). Ceramide can be metabolized via multiple routes, ensuring tight regulation of its cellular levels. Addition of phosphocholine generates sphingomyelin while carbohydrate is added to form glucosyl- or galactosylceramides. Ceramidase re-forms sphingosine or sphinganine from ceramide or dihydroceramide. Phosphorylation of ceramide generates ceramide phosphate. The determination of accurate kinetic parameters for many of the enzymes in the sphingolipid metabolic pathway is complicated by the lipophilic nature of the substrates.