title: Physiological roles of N-acetylglucosaminyltransferase V(GnT-V) in mice.
abstract: Oligosaccharide modification by N-acetylglucosaminyltransferase- V (GnT-V), a glycosyltransferase encoded by the Mgat5 gene that catalyzes the formation of β1,6GlcNAc (N-acetylglucosamine) branches on N-glycans, is thought to be associated with cancer growth and metastasis. Overexpression of GnT-V in cancer cells enhances the signaling of growth factors such as epidermal growth factor by increasing galectin-3 binding to polylactosamine structures on receptor N-glycans. In contrast, GnT-V deficient mice are born healthy and lack β1,6GlcNAc branches on N-glycans, but develop immunological disorders due to T-cell dysfunction at 12-20 months of age. We have developed Mgat5 transgenic (Tg) mice (GnT-V Tg mice) using a β-actin promoter and found characteristic phenotypes in skin, liver, and T cells in the mice. Although the GnT-V Tg mice do not develop spontaneous cancers in any organs, there are differences in the response to external stimuli between wild-type and GnT-V Tg mice. These changes are similar to those seen in cancer progression but are unexpected in some aspects. In this review, we summarize what is known about GnT-V functions in skin and liver cells as a means to understand the physiological roles of GnT-V in mice.
authors.affiliation: Department of Molecular Biochemistry and Clinical Investigation, Osaka University Graduate School of Medicine, Suita, Japan. emiyoshi@sahs.med.osaka-u.ac.jp
authors.forename: Eiji
authors.initials: E
authors.lastname: Miyoshi
authors.forename: Mika
authors.initials: M
authors.lastname: Terao
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Kamada
mesh_terms: D000199:Actins / Q000235:genetics / Q000378:metabolism; D000818:Animals; D058750:Epithelial-Mesenchymal Transition; D066246:ErbB Receptors / Q000378:metabolism; D008099:Liver / Q000201:enzymology; D008103:Liver Cirrhosis / Q000473:pathology; D017351:N-Acetylglucosaminyltransferases / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction; D012867:Skin / Q000201:enzymology
chemical_list: D000199:Actins; D017351:N-Acetylglucosaminyltransferases; C052254:alpha-1,6-mannosylglycoprotein beta 1,6-N-acetylglucosaminyltransferase; D066246:ErbB Receptors