Regulated expression and neural functions of human natural killer-1 (HNK-1) carbohydrate.
Human natural killer-1 (HNK-1) carbohydrate, comprising a unique trisaccharide HSO(3)-3GlcAβ1-3Galβ1-4GlcNAc, shows well-regulated expression and unique functions in the nervous system. Recent studies have revealed sophisticated and complicated expression mechanisms for HNK-1 glycan. Activities of biosynthetic enzymes are controlled through the formation of enzyme-complexes and regulation of subcellular localization. Functional aspects of HNK-1 carbohydrate were examined by overexpression, knockdown, and knockout studies of these enzymes. HNK-1 is involved in several neural functions such as synaptic plasticity, learning and memory, and the underlying molecular mechanisms have been illustrated upon identification of the target carrier glycoproteins of HNK-1 such as the glutamate receptor subunit GluA2 or tenascin-R. In this review, we describe recent findings about HNK-1 carbohydrate that provide further insights into the mechanism of its expression and function in the nervous system.
Disease Glycomics Team, Systems Glycobiology Research Group, Advanced Science Institute, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan. y.kizuka@riken.jp
Yasuhiko
Y
Kizuka
Shogo
S
Oka
D000818:Animals; D018959:CD57 Antigens / Q000096:biosynthesis / Q000737:chemistry / Q000502:physiology*; D002642:Chick Embryo; D049229:Dendritic Spines / Q000378:metabolism / Q000502:physiology; D000939:Epitopes / Q000096:biosynthesis / Q000737:chemistry; D018507:Gene Expression Regulation, Developmental; D014453:Glucuronosyltransferase / Q000235:genetics / Q000502:physiology; D006801:Humans; D051379:Mice; D008954:Models, Biological; D009420:Nervous System / Q000254:growth & development / Q000378:metabolism*; D009422:Nervous System Diseases / Q000235:genetics; D009473:Neuronal Plasticity; D011134:Polysaccharides / Q000096:biosynthesis / Q000737:chemistry / Q000502:physiology; D051381:Rats
D018959:CD57 Antigens; D000939:Epitopes; D011134:Polysaccharides; C111364:galactosylgalactoylxylosylprotein 3-beta-glucuronosyltransferase; D014453:Glucuronosyltransferase