Structure and mechanism of cancer-associated N-acetylglucosaminyltransferase-V

• Published in: Nature communications Vol. 9; no. 1; pp. 3380 - 12
• Main Authors: Nagae, Masamichi, Kizuka, Yasuhiko, Mihara, Emiko, Kitago, Yu, Hanashima, Shinya, Ito, Yukishige, Takagi, Junichi, Taniguchi, Naoyuki, Yamaguchi, Yoshiki
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 23.08.2018; Nature Publishing Group; Nature Portfolio
• Subjects: 631/45/221; 631/45/607/1172; 631/535/1266; 631/67; Antineoplastic Agents - pharmacology; Antineoplastic Agents - therapeutic use; Aromatic compounds; Biocatalysis; Cancer; Catalysis; Catalytic Domain - physiology; Cell surface; Crystal structure; Crystallography, X-Ray; Disease; Drug delivery; Drug Design; Drug development; Enzyme Assays; Glycan; Glycoproteins; Glycoproteins - chemistry; Glycoproteins - metabolism; Humanities and Social Sciences; Humans; Mannose; Metastases; Metastasis; Molecular Docking Simulation; multidisciplinary; Mutagenesis, Site-Directed; N-Acetylglucosamine; N-Acetylglucosaminyltransferases - antagonists & inhibitors; N-Acetylglucosaminyltransferases - chemistry; N-Acetylglucosaminyltransferases - genetics; N-Acetylglucosaminyltransferases - metabolism; N-Acetylglucosinyldiphosphodolichol N-acetylglucosaminyltransferase; N-glycans; Neoplasms - drug therapy; Neoplasms - pathology; Polysaccharides; Polysaccharides - chemistry; Polysaccharides - metabolism; Proteins; Receptors; Science; Science (multidisciplinary); Substrate Specificity; Substrates
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-018-05931-w

N -acetylglucosaminyltransferase-V (GnT-V) alters the structure of specific N -glycans by modifying α1-6-linked mannose with a β1-6-linked N -acetylglucosamine branch. β1-6 branch formation on cell surface receptors accelerates cancer metastasis, making GnT-V a promising target for drug development. However, the molecular basis of GnT-V’s catalytic mechanism and substrate specificity are not fully understood. Here, we report crystal structures of human GnT-V luminal domain with a substrate analog. GnT-V luminal domain is composed of a GT-B fold and two accessary domains. Interestingly, two aromatic rings sandwich the α1-6 branch of the acceptor N -glycan and restrain the global conformation, partly explaining the fine branch specificity of GnT-V. In addition, interaction of the substrate N -glycoprotein with GnT-V likely contributes to protein-selective and site-specific glycan modification. In summary, the acceptor-GnT-V complex structure suggests a catalytic mechanism, explains the previously observed inhibition of GnT-V by branching enzyme GnT-III, and provides a basis for the rational design of drugs targeting N -glycan branching. The activity of glycosyltransferase GnT-V correlates with cancer malignancy and poor prognosis but its mechanism of action is poorly understood. Here, the authors solve crystal structures of free and substrate analog-bound GnT-V, providing insights into its catalytic mechanism and a basis for GnT-V inhibition.