エンドウ トシヤ   ENDO TOSHIYA
  遠藤 斗志也
   所属   京都産業大学  生命科学部 先端生命科学科
   職種   客員教授
言語種別 英語
発行・発表の年月 2001/03
形態種別 研究論文
査読 査読あり
標題 Mnl1p, an alpha-mannosidase-like protein in yeast Saccharomyces cerevisiae, is required for endoplasmic reticulum-associated degradation of glycoproteins
執筆形態 その他
掲載誌名 JOURNAL OF BIOLOGICAL CHEMISTRY
出版社・発行元 AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC
巻・号・頁 276(12),pp.8635-8638
著者・共著者 K Nakatsukasa,S Nishikawa,N Hosokawa,K Nagata,T Endo
概要 The endoplasmic reticulum (ER) has a mechanism to block the exit of misfolded or unassembled proteins from the ER for the downstream organelles in the secretory pathway. Misfolded proteins retained in the ER are subjected to proteasome-dependent degradation in the cytosol when they cannot achieve correct folding and/or assembly within an appropriate time window. Although specific mannose trimming of the protein-bound oligosaccharide is essential for the degradation of misfolded glycoproteins, the precise mechanism for this recognition remains obscure. Here we report a new alpha -mannosidase-like protein, Mnl1p (mannosidase-like protein), in the yeast ER. Mnl1p is unlikely to exhibit alpha1,2-mannosidase activity, because it lacks cysteine residues that are essential for alpha1,2-mannosidase. However deletion of the MNL1 gene causes retardation of the degradation of misfolded carboxypeptidase Y, but not of the unglycosylated mutant form of the yeast alpha -mating pheromone. Possible roles of Mnl1p in the degradation and in the ER-retention of misfolded glycoproteins are discussed.
ISSN 0021-9258