Emerging concepts of ganglioside metabolism. Issue 23 (16th June 2018)

• Record Type: Journal Article
• Authors: Sandhoff, Roger; Sandhoff, Konrad
• Is Part Of: FEBS letters. Volume 592:Issue 23(2018)
• Page Start: 3835
• Page End: 3864
• Publication Date: 2018-06-16
• Subjects: catabolism -- endocytosis -- enzyme catalysis -- gangliosides -- lipid‐binding proteins -- membrane lipids -- metabolic diseases -- organellar membranes -- sphingolipids -- topology; Biochemistry -- Periodicals; Biophysics -- Periodicals; Molecular biology -- Periodicals; Biochimie -- Périodiques; Biochemistry; Biophysics; Molecular biology; Periodicals; 572.05
• DOI: 10.1002/1873-3468.13114
• Languages: English
• ISSNs: 0014-5793

Abstract

Abstract : Gangliosides (GGs) are sialic acid‐containing glycosphingolipids (GSLs) and major membrane components enriched on cellular surfaces. Biosynthesis of mammalian GGs starts at the cytosolic leaflet of endoplasmic reticulum (ER) membranes with the formation of their hydrophobic ceramide anchors. After intracellular ceramide transfer to Golgi and trans‐Golgi network (TGN) membranes, anabolism of GGs, as well as of other GSLs, is catalyzed by membrane‐spanning glycosyltransferases (GTs) along the secretory pathway. Combined activity of only a few promiscuous GTs allows for the formation of cell‐type‐specific glycolipid patterns. Following an exocytotic vesicle flow to the cellular plasma membranes, GGs can be modified by metabolic reactions at or near the cellular surface. For degradation, GGs are endocytosed to reach late endosomes and lysosomes. Whereas membrane‐spanning enzymes of the secretory pathway catalyze GSL and GG formation, a cooperation of soluble glycosidases, lipases and lipid‐binding cofactors, namely the sphingolipid activator proteins (SAPs), act as the main players of GG and GSL catabolism at intralysosomal luminal vesicles (ILVs). Abstract :