Molecular organization of the type II-A CRISPR adaptation module and its interaction with Cas9 via Csn2. Issue 18 (8th August 2018)

• Record Type: Journal Article
• Authors: Ka, Donghyun; Jang, Dong Man; Han, Byung Woo; Bae, Euiyoung
• Is Part Of: Nucleic acids research. Volume 46:Issue 18(2018)
• Page Start: 9805
• Page End: 9815
• Publication Date: 2018-08-08
• Subjects: Nucleic acids -- Periodicals; Molecular biology -- Periodicals; 572.805
• DOI: 10.1093/nar/gky702
• Languages: English
• ISSNs: 0305-1048

Abstract

Abstract: Clustered regularly interspaced short palindromic repeats (CRISPRs) and CRISPR-associated (Cas) proteins provide microbial adaptive immunity against invading foreign nucleic acids. In type II-A CRISPR–Cas systems, the Cas1–Cas2 integrase complex and the subtype-specific Csn2 comprise the CRISPR adaptation module, which cooperates with the Cas9 nuclease effector for spacer selection. Here, we report the molecular organization of the Streptococcus pyogenes type II-A CRISPR adaptation module and its interaction with Cas9 via Csn2. We determined the crystal structure of S. pyogenes type II-A Cas2. Chromatographic and calorimetric analyses revealed the stoichiometry and topology of the type II-A adaptation module composed of Cas1, Cas2 and Csn2. We also demonstrated that Cas9 interacts with Csn2 in a direct and stoichiometric manner. Our results reveal a network of molecular interactions among type II-A Cas proteins and highlight the role of Csn2 in coordinating Cas components involved in the adaptation and interference stages of CRISPR-mediated immunity.