8S9T

CRISPR-Cas type III-D effector complex

8S9T の概要

• エントリーDOI: 10.2210/pdb8s9t/pdb
• EMDBエントリー: 40248 40276 40296
• 分子名称: Cas7-Cas5-Cas11, TIGR03984 family CRISPR-associated protein, Cas10, ... (6 entities in total)
• 機能のキーワード: crispr, crispr-cas, type iii, complex, rna, crrna, rna binding protein
• 由来する生物種: Synechocystis sp. PCC 6803; 詳細
• タンパク質・核酸の鎖数: 6
• 化学式量合計: 332877.07

構造登録者

Schwartz, E.A.,Taylor, D.W. (登録日: 2023-03-30, 公開日: 2024-04-24, 最終更新日: 2024-05-01)

主引用文献

Schwartz, E.A.,Bravo, J.P.K.,Ahsan, M.,Macias, L.A.,McCafferty, C.L.,Dangerfield, T.L.,Walker, J.N.,Brodbelt, J.S.,Palermo, G.,Fineran, P.C.,Fagerlund, R.D.,Taylor, D.W.
RNA targeting and cleavage by the type III-Dv CRISPR effector complex.
Nat Commun, 15:3324-3324, 2024

PubMed Abstract: CRISPR-Cas are adaptive immune systems in bacteria and archaea that utilize CRISPR RNA-guided surveillance complexes to target complementary RNA or DNA for destruction. Target RNA cleavage at regular intervals is characteristic of type III effector complexes. Here, we determine the structures of the Synechocystis type III-Dv complex, an apparent evolutionary intermediate from multi-protein to single-protein type III effectors, in pre- and post-cleavage states. The structures show how multi-subunit fusion proteins in the effector are tethered together in an unusual arrangement to assemble into an active and programmable RNA endonuclease and how the effector utilizes a distinct mechanism for target RNA seeding from other type III effectors. Using structural, biochemical, and quantum/classical molecular dynamics simulation, we study the structure and dynamics of the three catalytic sites, where a 2'-OH of the ribose on the target RNA acts as a nucleophile for in line self-cleavage of the upstream scissile phosphate. Strikingly, the arrangement at the catalytic residues of most type III complexes resembles the active site of ribozymes, including the hammerhead, pistol, and Varkud satellite ribozymes. Our work provides detailed molecular insight into the mechanisms of RNA targeting and cleavage by an important intermediate in the evolution of type III effector complexes.

PubMed: 38637512
DOI: 10.1038/s41467-024-47506-y

実験手法

ELECTRON MICROSCOPY (2.52 Å)