4EDJ

Crystal structure of the GRASP55 GRASP Domain with a phosphomimetic mutation (S189D)

4EDJ の概要

• エントリーDOI: 10.2210/pdb4edj/pdb
• 関連するPDBエントリー: 3RLE
• 分子名称: Golgi reassembly-stacking protein 2, POTASSIUM ION (3 entities in total)
• 機能のキーワード: pdz domain, golgi tethering, membrane protein
• 由来する生物種: Homo sapiens (human)
• 細胞内の位置: Golgi apparatus membrane; Lipid-anchor: Q9H8Y8
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 45798.17

構造登録者

Truschel, S.T.,Zhang, M.,Bachert, C.,Macbeth, M.R.,Linstedt, A.D. (登録日: 2012-03-27, 公開日: 2012-05-09, 最終更新日: 2023-09-13)

主引用文献

Truschel, S.T.,Zhang, M.,Bachert, C.,Macbeth, M.R.,Linstedt, A.D.
Allosteric Regulation of GRASP Protein-dependent Golgi Membrane Tethering by Mitotic Phosphorylation.
J.Biol.Chem., 287:19870-19875, 2012

PubMed Abstract: Mitotic phosphorylation of the conserved GRASP domain of GRASP65 disrupts its self-association, leading to a loss of Golgi membrane tethering, cisternal unlinking, and Golgi breakdown. Recently, the structural basis of the GRASP self-interaction was determined, yet the mechanism by which phosphorylation disrupts this activity is unknown. Here, we present the crystal structure of a GRASP phosphomimic containing an aspartic acid substitution for a serine residue (Ser-189) that in GRASP65 is phosphorylated by PLK1, causing a block in membrane tethering and Golgi ribbon formation. The structure revealed a conformational change in the GRASP internal ligand that prevented its insertion into the PDZ binding pocket, and gel filtration assays showed that this phosphomimic mutant exhibited a significant reduction in dimer formation. Interestingly, the structure also revealed an apparent propagation of conformational change from the site of phosphorylation to the shifted ligand, and alanine substitution of two residues (Glu-145 and Ser-146) at penultimate positions in this chain rescued dimer formation by the phosphomimic. These data reveal the structural basis of the phosphoinhibition of GRASP-mediated membrane tethering and provide a mechanism for its allosteric regulation.

PubMed: 22523075
DOI: 10.1074/jbc.M111.326256

実験手法

X-RAY DIFFRACTION (1.901 Å)