title: CRISPR-Cas adaptation: insights into the mechanism of action.
abstract: Since the first demonstration that CRISPR-Cas systems provide bacteria and archaea with adaptive immunity against phages and plasmids, numerous studies have yielded key insights into the molecular mechanisms governing how these systems attack and degrade foreign DNA. However, the molecular mechanisms underlying the adaptation stage, in which new immunological memory is formed, have until recently represented a major unresolved question. In this Progress article, we discuss recent discoveries that have shown both how foreign DNA is identified by the CRISPR-Cas adaptation machinery and the molecular basis for its integration into the chromosome to form an immunological memory. Furthermore, we describe the roles of each of the specific CRISPR-Cas components that are involved in memory formation, and consider current models for their evolutionary origin.
authors.affiliation: Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel.
authors.forename: Gil
authors.initials: G
authors.lastname: Amitai
authors.affiliation: Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel.
authors.forename: Rotem
authors.initials: R
authors.lastname: Sorek
mesh_terms: D056704:Adaptive Immunity / Q000235:genetics / Q000502:physiology; D000818:Animals; D001105:Archaea / Q000235:genetics; D001419:Bacteria / Q000235:genetics; D005075:Biological Evolution; D064130:CRISPR-Associated Proteins / Q000235:genetics / Q000378:metabolism*; D064113:CRISPR-Cas Systems / Q000502:physiology*; D018797:Cell Cycle Proteins; D064112:Clustered Regularly Interspaced Short Palindromic Repeats / Q000235:genetics / Q000502:physiology*; D004247:DNA / Q000235:genetics*; D021901:DNA, Intergenic / Q000235:genetics; D005786:Gene Expression Regulation / Q000502:physiology; D012313:RNA / Q000235:genetics; D012097:Repressor Proteins; D029701:Saccharomyces cerevisiae Proteins
chemical_list: C089931:CDC36 protein, S cerevisiae; D064130:CRISPR-Associated Proteins; D018797:Cell Cycle Proteins; D021901:DNA, Intergenic; D012097:Repressor Proteins; D029701:Saccharomyces cerevisiae Proteins; D012313:RNA; D004247:DNA