Structure and function of beta2-glycoprotein I

β2-糖蛋白 I 的结构和功能

• 批准号: 07680650
• 负责人: GOTO Yuji
• 金额: $ 1.41万
• 依托单位: Osaka University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1996
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07680650/
• 关键词: Glycoprotein; beta2-Glycoprotein I; Phospholipid; Yeast; NMR; Domain; Isotope label; β2-グリコプロテインI; 安定同位体ラベル; ドメイン; タンパク質

beta2-Glycoprotein I (beta2GPI) is a cofactor in the recognition of the phospholipid antigen cardiolipin by anti-cardiolipin antibodies in autoimmune diseases such as systemic lupus erythematosus. beta2GPI (326 amino acids) consists of five repeating units (Domains I-V), each containing 60-80 amino acid residues, corresponding to the short consensus repeat of the complement control protein module. Recent studies suggest that Domain V plays important roles in the binding to cardiolipin and expression of cofactor activity. We studied the structure-function relationship of beta2GPI by preparing various derivatives.1.We examined the interactions of various forms of bovine beta2GPI with phospholipid liposomes under different conditions. The results indicate that the N-terminal as well as C-terminal domains have an important role in the interaction of beta2GPI with cardiolipin, and that the three residual domains containing sialic acid have no significant effect on the interaction.2.We constructed a high-level expression system for human Domain V using a methylotrophic yeast, Pichia pastoris. We found that the recombinant protein as the native disulfide bonds and a proper folded structure. For the three dimensional structure determination by NMR,with this expression system, we prepared 15N and 13C labeled Domain V.The NMR studies are on going.3.Conformation, stability, and liposome-binding activity of the recombinant Domain V were characterized and compared with those of various beta2GPI derivatives. The results suggested that the region including Trp76-Thr78 has a critical role in binding to cardiolipin.4.A nicked form of domain V in beta2GPI has been shown to have a lower ability to cardiolipin. Using the recombinant Domain V,we found that plasmin can produce the nicked form of domain V,suggesting the biological significance.

β 2-糖蛋白I（β 2GPI）是自身免疫性疾病如系统性红斑狼疮中抗心磷脂抗体识别磷脂抗原心磷脂的辅助因子。β 2GPI（326个氨基酸）由5个重复单元（结构域I-V）组成，每个单元含有60-80个氨基酸残基，对应于补体控制蛋白模块的短共有重复序列。最近的研究表明，结构域V在与心磷脂的结合和辅因子活性的表达中起重要作用。通过制备不同的衍生物，研究了beta2 GPI的结构与功能的关系。1.考察了不同形式的牛beta2 GPI在不同条件下与磷脂脂质体的相互作用。结果表明，β 2GPI的N端和C端结构域在其与心磷脂的相互作用中起重要作用，而含有唾液酸的三个残基结构域对相互作用无明显影响。2.构建了人结构域V在甲醇酵母中的高效表达系统。重组蛋白具有天然的二硫键和正确的折叠结构.在三维结构的核磁共振测定方面，我们利用该表达系统制备了15 N和13 C标记的Domain V，核磁共振研究正在进行中。3.对重组Domain V的构象、稳定性和脂质体结合活性进行了表征，并与各种β 2 GPI衍生物进行了比较。结果表明，包括Trp 76-Thr 78的区域在与心磷脂结合中起关键作用。4. β 2GPI中V结构域的切口形式已被证明具有较低的与心磷脂结合的能力。利用重组的结构域V，我们发现纤溶酶可以产生切口形式的结构域V，提示了其生物学意义。

项目成果

Hagihara, Y.: "Role of the N-and C-terminal domains of bovine β2-glycoprotein I in its interaction with cardiolipin" J. Biochem.118. 129-136 (1995)

Hagihara, Y.：“牛 β2-糖蛋白 I 的 N 端和 C 端结构域在其与心磷脂相互作用中的作用”J. Biochem.118（1995）。

Yoshihisa Hagihara: "Structure and function of beta2-glycoprotein I : with special reference to the interaction with phospholipid." Lupus. 4. S3-S5 (1995)

Yoshihisa Hagihara：“β2-糖蛋白 I 的结构和功能：特别是与磷脂的相互作用。”

Yoshihisa Hagihara: "Role of the N-and C-terminal domains of bovine beta2-glyco-protein I in its interaction with cardiolipin." J.Biochem.118. 129-136 (1995)

Yoshihisa Hagihara：“牛 β2-糖蛋白 I 的 N 端和 C 端结构域在与心磷脂相互作用中的作用。”

Hagihara,Y.: "Structure and function of the recombinant fifth domain of human β2-glyco-protein I" J.Biocchem.121. 128-137 (1997)

Hagihara, Y.：“人 β2-糖蛋白 I 的重组第五结构域的结构和功能”J.Biocchem.128-137 (1997)。

萩原義久: "β2グリコプロテインIの製造と機能" Modern physician. 15. 1555-1559 (1995)

Yoshihisa Hagiwara：“β2糖蛋白I的产生和功能”现代医师15。1555-1559（1995）。