1RI2

Structure and mechanism of mRNA cap (guanine N-7) methyltransferase

1RI2 の概要

• エントリーDOI: 10.2210/pdb1ri2/pdb
• 関連するPDBエントリー: 1RI1 1RI3 1RI4 1RI5
• 分子名称: mRNA CAPPING ENZYME, 7-METHYL-GUANOSINE-5'-TRIPHOSPHATE-5'-GUANOSINE (3 entities in total)
• 機能のキーワード: methyltransferase, rna, cap, m7g, messenger rna cap, transferase
• 由来する生物種: Encephalitozoon cuniculi
• 細胞内の位置: Nucleus (By similarity): Q8SR66
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 35627.12

構造登録者

Fabrega, C.,Hausmann, S.,Shen, V.,Shuman, S.,Lima, C.D. (登録日: 2003-11-16, 公開日: 2004-02-03, 最終更新日: 2024-02-14)

主引用文献

Fabrega, C.,Hausmann, S.,Shen, V.,Shuman, S.,Lima, C.D.
Structure and mechanism of mRNA cap (Guanine-n7) methyltransferase
Mol.Cell, 13:77-89, 2004

PubMed Abstract: A suite of crystal structures is reported for a cellular mRNA cap (guanine-N7) methyltransferase in complex with AdoMet, AdoHcy, and the cap guanylate. Superposition of ligand complexes suggests an in-line mechanism of methyl transfer, albeit without direct contacts between the enzyme and either the N7 atom of guanine (the attacking nucleophile), the methyl carbon of AdoMet, or the sulfur of AdoMet/AdoHcy (the leaving group). The structures indicate that catalysis of cap N7 methylation is accomplished by optimizing proximity and orientation of the substrates, assisted by a favorable electrostatic environment. The enzyme-ligand structures, together with new mutational data, fully account for the biochemical specificity of the cap guanine-N7 methylation reaction, an essential and defining step of eukaryotic mRNA synthesis.

PubMed: 14731396
DOI: 10.1016/S1097-2765(03)00522-7

実験手法

X-RAY DIFFRACTION (2.7 Å)