Roles of glycolipids in the development and maintenance of nervous tissues

Glycoshingolipids are involved in a wide variety of biological events, including cell proliferation, differentiation, development, regeneration, and apoptosis in vertebrates. Expression profiles of glycolipids during the development and cell differentiation or transformation suggest that glycolipids are largely implicated in the determination of cell fates by directly transducing biosignals as receptors and/or modulating receptors' function. Despite of a number of efforts to clarify the molecular functions of glycolipids, no unambiguous results have been obtained until genetic modification of glycolipids became possible. Recent progress in the isolation of cDNAs of glycosphingolipid synthase genes has enabled us to examine roles of glycosphingolipids and strongly promoted further understanding of significances of glycosphingolipids. In particular, knock-out mice of glycosyltransferases showed quite novel aspects of glycolipid function and also redundancy among similar enzymes and glycolipid structures. Here, we summarize analytical methods with which roles of glycolipids in the development and maintenance of nervous tissues, including techniques to establish transgenic mice and gene knock-out mice, to survey fundamental behavior abnormalities, and to examine fine morphological changes lying under abnormal phenotypes of the glycolipids-modified cells and glycolipid-lacking mutant mice.