8PJ4

Structure of human 48S translation initiation complex after eIF5 release (48S-4)

これはPDB形式変換不可エントリーです。

8PJ4 の概要

• エントリーDOI: 10.2210/pdb8pj4/pdb
• EMDBエントリー: 17699
• 分子名称: Eukaryotic translation initiation factor 5B, 60S ribosomal protein L41, 18S rRNA, ... (57 entities in total)
• 機能のキーワード: ribosome, translation, initiation, 48s, eif, human, eukaryotic, factor, codon, scanning, closed
• 由来する生物種: Homo sapiens (human); 詳細
• タンパク質・核酸の鎖数: 53
• 化学式量合計: 2351598.33

構造登録者

Petrychenko, V.,Yi, S.-H.,Liedtke, D.,Peng, B.Z.,Rodnina, M.V.,Fischer, N. (登録日: 2023-06-22, 公開日: 2024-08-14, 最終更新日: 2025-01-29)

主引用文献

Petrychenko, V.,Yi, S.H.,Liedtke, D.,Peng, B.Z.,Rodnina, M.V.,Fischer, N.
Structural basis for translational control by the human 48S initiation complex.
Nat.Struct.Mol.Biol., 32:62-72, 2025

PubMed Abstract: The selection of an open reading frame (ORF) for translation of eukaryotic mRNA relies on remodeling of the scanning 48S initiation complex into an elongation-ready 80S ribosome. Using cryo-electron microscopy, we visualize the key commitment steps orchestrating 48S remodeling in humans. The mRNA Kozak sequence facilitates mRNA scanning in the 48S open state and stabilizes the 48S closed state by organizing the contacts of eukaryotic initiation factors (eIFs) and ribosomal proteins and by reconfiguring mRNA structure. GTPase-triggered large-scale fluctuations of 48S-bound eIF2 facilitate eIF5B recruitment, transfer of initiator tRNA from eIF2 to eIF5B and the release of eIF5 and eIF2. The 48S-bound multisubunit eIF3 complex controls ribosomal subunit joining by coupling eIF exchange to gradual displacement of the eIF3c N-terminal domain from the intersubunit interface. These findings reveal the structural mechanism of ORF selection in human cells and explain how eIF3 could function in the context of the 80S ribosome.

PubMed: 39289545
DOI: 10.1038/s41594-024-01378-4

実験手法

ELECTRON MICROSCOPY (3.2 Å)