Molecular mechanism of GPI anchir biosynthesis

GPI anchir生物合成的分子机制

• 批准号: 09480151
• 负责人: KINOSHITA Taroh
• 金额: $ 8.19万
• 依托单位: Osaka University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09480151/
• 关键词: GPI anchor; post-translational modification; endoplasmic reticulum; biosynthesis; glycosyltransferase

Our goal is to clarify molecular mechanisms of GPI anchor biosynthesis. During last two years we have made following three progresses. 1) Early steps. We cloned human GPI1 and showed that PIG-A, PIG-H, PIG-C and GPI1 proteins farm a complex and that the protein complex is the N-acetylglucosaminyl transferase that mediates the first step (Watanabe et al., EMBO J, 1998, 17 : 877-885). We demonstrated that PIG-L is the N-acetyiglucosaminyl phosphatidylinositol de-N-acetylase that mediates the second step (Watanabe et al, Biochemical J, in press).2) Regarding biosynthesis of dolichol-phosphate-mannose (Dol-P-Man), a donor of three mannoses used in GPI, we showed that a mammalian homologue of yeast Dol-P-Man synthase Dpmlp is not sufficient for biosynthesis of Dol-P-Man in mammalian cells (Tomita et al, J Biol Chem, 1998, 273 : 9249-9254). We then cloned rat DPM2 and showed that Dpm2p is necessary for stable expression and localization of catalytic Dpmlp in the endoplasmic reticulum (Maeda et al, EMBO J, 1998, 17 : 4920-4929).3) Regarding an enzyme that transfers preassembled GPI to proteins, we demonstrated that GAA1 is a subunit that recognizes GPI attachment signal sequence (Ohishi et al, submitted for publication).

我们的目标是阐明GPI锚生物合成的分子机制。在过去的两年里，我们取得了以下三个进展。1)早期步骤。我们克隆了人GPI 1，并表明PIG-A、PIG-H、PIG-C和GPI 1蛋白质形成一个复合物，并且该蛋白质复合物是介导第一步的N-乙酰葡糖胺转移酶（Watanabe等人，EMBO J，1998，17：877-885）。我们证明PIG-L是介导第二步的N-乙酰葡糖胺磷脂酰肌醇脱N-乙酰化酶（Watanabe等，Biochemical J，出版中）。2）关于长醇-磷酸-甘露糖的生物合成（Dol-P-Man），在GPI中使用的三种甘露糖的供体，我们表明酵母Dol-P-Man合酶Dpmlp的哺乳动物同源物不足以在哺乳动物细胞中生物合成Dol-P-Man（Tomita等人，J Biol Chem，1998，273：9249-9254）。然后，我们克隆了大鼠DPM 2，并表明Dpm 2 p对于催化性Dpmlp在内质网中的稳定表达和定位是必需的（Maeda等，EMBO J，1998，17：4920-4929）。3）关于将预组装的GPI转移到蛋白质的酶，我们证明GAA 1是识别GPI附着信号序列的亚基（Ohishi等，提交出版）。

项目成果

Hong,Y.: "Structure and chromosomal localizations of the glycosylphosphatidylinositol synthesis gene PIGC and its pseudogene PIGCP1.Genomics,44 : 347-349" Genomics. 44. 347-349 (1997)

Hong，Y.：“糖基磷脂酰肌醇合成基因 PIGC 及其假基因 PIGCP1 的结构和染色体定位。基因组学，44：347-349”基因组学。

Watanabe,R.: "The first step of glycosylphosphatidylinositol biosynthesis is mediated by a complex of PIG-A,PIG-H,PIG-C and GPI1." EMBO J.17. 877-885 (1998)

Watanabe,R.：“糖基磷脂酰肌醇生物合成的第一步是由 PIG-A、PIG-H、PIG-C 和 GPI1 复合物介导的。”

Tomita,S: "A homologue of Saccharomyces cerevisiae Dpmlp is not sufficient for synthesis of dolichol-phosphate-mannose in mammalian cells. J.Biol.Chem. 237 : 9249-9254." J.Biol.Chem.273. 9249-9254 (1998)

Tomita,S：“酿酒酵母 Dpmlp 的同源物不足以在哺乳动物细胞中合成多甘醇-磷酸-甘露糖。J.Biol.Chem. 237：9249-9254。”

Maeda, Y., S.Tomita, R.Watanabe, K.Ohishi and T.Kinoshita.: "DPM2 regulates biosynthesis of dolichol phosphate-mannose in mammalian cells : correct subcellular localization and stabilization of DPM1, and binding of dolichol phosphate." EMBO J.17. 4920-492

Maeda, Y.、S.Tomita、R.Watanabe、K.Ohishi 和 T.Kinoshita.：“DPM2 调节哺乳动物细胞中磷酸多萜醇-甘露糖的生物合成：正确的亚细胞定位和 DPM1 的稳定性，以及磷酸多醇醇的结合。”

Watanabe,R.: "The first step of glycosylphosphatidylinositol biosynthesis is mediated by a complex of PIG-A,PIG-H,PIG-C and GPII." EMBO J.17. 877-885 (1998)

Watanabe,R.：“糖基磷脂酰肌醇生物合成的第一步是由 PIG-A、PIG-H、PIG-C 和 GPII 复合物介导的。”