title: N-Glycosylation is essential for the secretion of extracellular superoxide dismutase.
abstract: Extracellular superoxide dismutase (EC-SOD or SOD3) protects against various oxidative stress-related diseases by scavenging reactive superoxides in the extracellular space. It is the only SOD isozyme that is secreted and glycosylated (at asparagine 89). However, the physiological roles of its glycosylation are poorly understood. In this study, we found that the glycosylation site on EC-SOD is well conserved and that a glycosylation-deficient EC-SOD mutant retains its enzymatic activity, but is not secreted. This impairment in secretion may, in part, be due to the ability of the mutants to form unusual higher order oligomers. Our findings reveal that the glycan modification is a key regulator of EC-SOD secretion and contributes to the understanding of the roles of glycans in EC-SOD-related diseases.
authors: Systems Glycobiology Research Group, RIKEN-Max Plank Joint Research Center for Systems Chemical Biology, Global Research Cluster, RIKEN, Wako, Saitama, Japan.
authors: Fumi
authors: F
authors: Ota
authors: Systems Glycobiology Research Group, RIKEN-Max Plank Joint Research Center for Systems Chemical Biology, Global Research Cluster, RIKEN, Wako, Saitama, Japan.
authors: Yasuhiko
authors: Y
authors: Kizuka
authors: Systems Glycobiology Research Group, RIKEN-Max Plank Joint Research Center for Systems Chemical Biology, Global Research Cluster, RIKEN, Wako, Saitama, Japan.
authors: Shinobu
authors: S
authors: Kitazume
authors: Laboratory of Clinical Pharmaceutics, Gifu Pharmaceutical University, Gifu, Gifu, Japan.
authors: Tetsuo
authors: T
authors: Adachi
authors: Systems Glycobiology Research Group, RIKEN-Max Plank Joint Research Center for Systems Chemical Biology, Global Research Cluster, RIKEN, Wako, Saitama, Japan. dglycotani@riken.jp.
authors: Naoyuki
authors: N
authors: Taniguchi
mesh_terms: D006031:Glycosylation; D057809:HEK293 Cells; D006801:Humans; D011499:Protein Processing, Post-Translational; D021381:Protein Transport; D055571:Secretory Pathway; D013482:Superoxide Dismutase / Q000737:chemistry / Q000378:metabolism*
chemical_list: D013482:Superoxide Dismutase
keywords: extracellular superoxide dismutase; glycan; secretion