GangliosideGM1is a monosialylated ganglioside and the prototypic ganglioside for those containing one sialic acid residue.1,2It is found in a large variety of cells, including immune cells and neurons, and is enriched in lipid rafts in the cell membrane.3It associates with growth factor receptors, including TrkA, TrkB, and the GDNF receptor complex containing Ret and GFRα, and is required for TrkA expression on the cell surface. GangliosideGM1interacts with other proteins to increase calcium influx, affecting various calcium-dependent processes, including inducing neuronal outgrowth during differentiation. GangliosideGM1acts as a receptor for cholera toxin, which binds to its oligosaccharide group, facilitating toxin cell entry into epithelial cells of the jejunum.4,5Similarly, it is bound by the heat-labile enterotoxin fromE. coliin the pathogenesis of traveler's diarrhea.6GangliosideGM1gangliosidosis, characterized by a deficiency in GM1-β-galactosidase, the enzyme that degrades gangliosideGM1, leads to accumulation of the gangliosides GM1and GA1in neurons and can be fatal in infants.1Levels of gangliosideGM1are decreased in the substantia nigra pars compacta in postmortem brain from patients with Parkinson's disease.3GangliosideGM1mixture contains a mixture of ovinegangliosideGM1molecular species with primarily C18:0 fatty acyl chain lengths, among various others. [Matreya, LLC. Catalog No. 1544] 1.Kolter, T.Ganglioside biochemistryISRN Biochem.506160(2012) 2.Mocchetti, I.Exogenous gangliosides, neuronal plasticity and repair, and the neurotrophinsCell Mol. Life Sci.62(19-20)2283-2294(2005) 3.Ledeen, R.W., and Wu, G.The multi-tasked life of GM1 ganglioside, a true factotum of natureTrends Biochem. Sci.40(7)407-418(2015) 4.Turnbull, W.B., Precious, B.L., and Homans, S.W.Dissecting the cholera toxin-gangliosideGM1 interaction by isothermal titration calorimetryJ. Am. Chem. Soc.126(4)1047-1054(2004) 5.Blank, N., Schiller, M., Krienke, S., et al.Cholera toxin binds to lipid rafts but has a limited specificity for gangliosideGM1Immunol. Cell Biol.85(5)378-382(2007) 6.Minke, W.E., Roach, C., Hol, W.G., et al.Structure-based exploration of the gangliosideGM1 binding sites of Escherichia coli heat-labile enterotoxin and cholera toxin for the discovery of receptor antagonistsBiochemistry38(18)5684-5692(1999)