Ganglioside glycosyltransferases are S-acylated at conserved cysteine residues involved in homodimerization

CHUMPEN RAMIREZ, SABRINA; RUGGIERO, FERNANDO M; DANIOTTI, JOSE LUIS; VALDEZ TAUBAS, JAVIER

BIOCHEMICAL JOURNAL

PORTLAND PRESS LTD

Año: 2017 vol. 474 p. 2803 - 2803

0264-6021

anglioside glycosyltransferases (GGTs) are type-II membrane proteins bearing a short N-terminal cytoplasmic tail, a transmembrane domain (TMD), and a lumenal catalytic domain. The expression and activity of these enzymes largely determine the quality of the glycolipids that decorate mammalian cells membranes. Many glycosyltransferases are themselves glycosylated and this is important for their proper localisation, but few if any other post-translational modifications of these proteins have been reported. Here we show that the GGTs, ST3Gal-V, ST8Sia-I, and β4GalNAcT-I are S-acylated at conserved cysteine residues located close the cytoplasmic border of their TMDs. ST3Gal-II, a GT that sialylates glycolipids and glycoproteins, is also S-acylated at a conserved cysteine located in the N-terminal cytoplasmic tail. Many others GTs also possess cysteine residues in their cytoplasmic regions suggesting that this modification occurs on these GTs as well. S-acylation, commonly known as pa