5M72

Structure of the human SRP68-72 protein-binding domain complex

5M72 の概要

• エントリーDOI: 10.2210/pdb5m72/pdb
• 分子名称: Signal recognition particle subunit SRP72, Signal recognition particle subunit SRP68, SULFATE ION, ... (6 entities in total)
• 機能のキーワード: protein targeting, signal recognition particle, tetratricopeptide repeat, protein-peptide complex, protein transport
• 由来する生物種: Homo sapiens (Human); 詳細
• 細胞内の位置: Cytoplasm : O76094 Q9UHB9
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 26692.23

構造登録者

Becker, M.M.M.,Wild, K.,Sinning, I. (登録日: 2016-10-26, 公開日: 2016-12-07, 最終更新日: 2024-05-08)

主引用文献

Becker, M.M.,Lapouge, K.,Segnitz, B.,Wild, K.,Sinning, I.
Structures of human SRP72 complexes provide insights into SRP RNA remodeling and ribosome interaction.
Nucleic Acids Res., 45:470-481, 2017

PubMed Abstract: Co-translational protein targeting and membrane protein insertion is a fundamental process and depends on the signal recognition particle (SRP). In mammals, SRP is composed of the SRP RNA crucial for SRP assembly and function and six proteins. The two largest proteins SRP68 and SRP72 form a heterodimer and bind to a regulatory site of the SRP RNA. Despite their essential roles in the SRP pathway, structural information has been available only for the SRP68 RNA-binding domain (RBD). Here we present the crystal structures of the SRP68 protein-binding domain (PBD) in complex with SRP72-PBD and of the SRP72-RBD bound to the SRP S domain (SRP RNA, SRP19 and SRP68) detailing all interactions of SRP72 within SRP. The SRP72-PBD is a tetratricopeptide repeat, which binds an extended linear motif of SRP68 with high affinity. The SRP72-RBD is a flexible peptide crawling along the 5e- and 5f-loops of SRP RNA. A conserved tryptophan inserts into the 5e-loop forming a novel type of RNA kink-turn stabilized by a potassium ion, which we define as K-turn. In addition, SRP72-RBD remodels the 5f-loop involved in ribosome binding and visualizes SRP RNA plasticity. Docking of the S domain structure into cryo-electron microscopy density maps reveals multiple contact sites between SRP68/72 and the ribosome, and explains the role of SRP72 in the SRP pathway.

PubMed: 27899666
DOI: 10.1093/nar/gkw1124

実験手法

X-RAY DIFFRACTION (1.6 Å)