2A6Y

Crystal structure of Emp47p carbohydrate recognition domain (CRD), tetragonal crystal form

2A6Y の概要

• エントリーDOI: 10.2210/pdb2a6y/pdb
• 関連するPDBエントリー: 1GV9 1R1Z 2A6V 2A6W 2A6X 2A6Z 2A70 2A71
• 分子名称: Emp47p (form1), SULFATE ION (3 entities in total)
• 機能のキーワード: beta sandwich, carbohydrate binding protein, cargo receptor, structural genomics, nppsfa, national project on protein structural and functional analyses, sugar binding protein
• 由来する生物種: Saccharomyces cerevisiae (baker's yeast)
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 28691.71

構造登録者

Satoh, T.,Sato, K.,Kanoh, A.,Yamashita, K.,Kato, R.,Nakano, A.,Wakatsuki, S. (登録日: 2005-07-04, 公開日: 2006-01-31, 最終更新日: 2024-10-23)

主引用文献

Satoh, T.,Sato, K.,Kanoh, A.,Yamashita, K.,Yamada, Y.,Igarashi, N.,Kato, R.,Nakano, A.,Wakatsuki, S.
Structures of the carbohydrate recognition domain of Ca2+-independent cargo receptors Emp46p and Emp47p.
J.Biol.Chem., 281:10410-10419, 2006

PubMed Abstract: Emp46p and Emp47p are type I membrane proteins, which cycle between the endoplasmic reticulum (ER) and the Golgi apparatus by vesicles coated with coat protein complexes I and II (COPI and COPII). They are considered to function as cargo receptors for exporting N-linked glycoproteins from the ER. We have determined crystal structures of the carbohydrate recognition domains (CRDs) of Emp46p and Emp47p of Saccharomyces cerevisiae, in the absence and presence of metal ions. Both proteins fold as a beta-sandwich, and resemble that of the mammalian ortholog, p58/ERGIC-53. However, the nature of metal binding is distinct from that of Ca(2+)-dependent p58/ERGIC-53. Interestingly, the CRD of Emp46p does not bind Ca(2+) ion but instead binds K(+) ion at the edge of a concave beta-sheet whose position is distinct from the corresponding site of the Ca(2+) ion in p58/ERGIC-53. Binding of K(+) ion to Emp46p appears essential for transport of a subset of glycoproteins because the Y131F mutant of Emp46p, which cannot bind K(+) ion fails to rescue the transport in disruptants of EMP46 and EMP47 genes. In contrast the CRD of Emp47p binds no metal ions at all. Furthermore, the CRD of Emp46p binds to glycoproteins carrying high mannosetype glycans and the is promoted by binding not the addition of Ca(2+) or K(+) ion in These results suggest that Emp46p can be regarded as a Ca(2+)-independent intracellular lectin at the ER exit sites.

PubMed: 16439369
DOI: 10.1074/jbc.M512258200

実験手法

X-RAY DIFFRACTION (1.42 Å)