Hidemi Arakawa, Akira Togayachi
Lacto-N-tetraose (LNT) and lacto-N-neotetraose (LNnT) are structures expressed in glycoproteins and are key structural components of lacto/neolacto-series glycolipids. These glycans are involved in the expression of carbohydrate antigens, such as blood group antigens, on glycolipids, and are found in leukocytes and other cell types. The β1,3-N-acetylglucosaminyltransferase 5 β3GnT5 enzyme, encoded by the N, plays a pivotal role in the biosynthesis of lacto/neolacto-series glycolipids by catalyzing the synthesis of lactotriaosylceramide, which serves as a precursor of these glycolipids. β3GnT5 transfers N-acetylglucosamine (GlcNAc) from UDP-GlcNAc to lactosylceramide (LacCer). These glycolipids are crucial for various physiological functions, including immune responses, cell-cell interactions, hematopoietic differentiation, and neural development. In this study, we provide an overview of the methods used to analyze lacto- and neolacto-series of glycolipids and gangliosides.