6O7H

Cryo-EM structure of Csm-crRNA-target RNA ternary complex in complex with cA4 in type III-A CRISPR-Cas system

6O7H の概要

• エントリーDOI: 10.2210/pdb6o7h/pdb
• EMDBエントリー: 0641
• 分子名称: CRISPR system single-strand-specific deoxyribonuclease Cas10/Csm1 (subtype III-A), GUANOSINE-5'-MONOPHOSPHATE, Csm2, ... (10 entities in total)
• 機能のキーワード: cryo-em structure, csm-crrna-target rna ternary complex in complex with ca4, type iii crispr-cas systerm, immune system, immune system-rna-dna complex, immune system-rna complex, immune system/rna/dna
• 由来する生物種: Thermococcus onnurineus (strain NA1); 詳細
• タンパク質・核酸の鎖数: 9
• 化学式量合計: 276608.86

構造登録者

Jia, N.,Patel, D.J. (登録日: 2019-03-07, 公開日: 2019-07-31, 最終更新日: 2024-10-16)

主引用文献

Jia, N.,Jones, R.,Sukenick, G.,Patel, D.J.
Second Messenger cA4Formation within the Composite Csm1 Palm Pocket of Type III-A CRISPR-Cas Csm Complex and Its Release Path.
Mol.Cell, 75:933-943.e6, 2019

PubMed Abstract: Target RNA binding to crRNA-bound type III-A CRISPR-Cas multi-subunit Csm surveillance complexes activates cyclic-oligoadenylate (cA) formation from ATP subunits positioned within the composite pair of Palm domain pockets of the Csm1 subunit. The generated cA second messenger in turn targets the CARF domain of trans-acting RNase Csm6, triggering its HEPN domain-based RNase activity. We have undertaken cryo-EM studies on multi-subunit Thermococcus onnurineus Csm effector ternary complexes, as well as X-ray studies on Csm1-Csm4 cassette, both bound to substrate (AMPPNP), intermediates (pppA), and products (cA), to decipher mechanistic aspects of cA formation and release. A network of intermolecular hydrogen bond alignments accounts for the observed adenosine specificity, with ligand positioning dictating formation of linear pppA intermediates and subsequent cA formation by cyclization. We combine our structural results with published functional studies to highlight mechanistic insights into the role of the Csm effector complex in mediating the cA signaling pathway.

PubMed: 31326272
DOI: 10.1016/j.molcel.2019.06.013

実験手法

ELECTRON MICROSCOPY (2.9 Å)