title: Adaptation in CRISPR-Cas Systems.
abstract: Clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated (Cas) proteins constitute an adaptive immune system in prokaryotes. The system preserves memories of prior infections by integrating short segments of foreign DNA, termed spacers, into the CRISPR array in a process termed adaptation. During the past 3 years, significant progress has been made on the genetic requirements and molecular mechanisms of adaptation. Here we review these recent advances, with a focus on the experimental approaches that have been developed, the insights they generated, and a proposed mechanism for self- versus non-self-discrimination during the process of spacer selection. We further describe the regulation of adaptation and the protein players involved in this fascinating process that allows bacteria and archaea to harbor adaptive immunity.
authors.affiliation: Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Tel Aviv University, Tel Aviv 69978, Israel.
authors.forename: Samuel H
authors.initials: SH
authors.lastname: Sternberg
authors.affiliation: Department of Regulation in Infection Biology, Helmholtz Centre for Infection Research, Braunschweig 38124, Germany; Department of Regulation in Infection Biology, Max Planck Institute for Infection Biology, Berlin 10117, Germany.
authors.forename: Hagen
authors.initials: H
authors.lastname: Richter
authors.affiliation: Department of Regulation in Infection Biology, Helmholtz Centre for Infection Research, Braunschweig 38124, Germany; Department of Regulation in Infection Biology, Max Planck Institute for Infection Biology, Berlin 10117, Germany; The Laboratory for Molecular Infection Medicine Sweden, Department of Molecular Biology, Umeå Centre for Microbial Research, Umeå University, Umeå 90187, Sweden; Hannover Medical School, Hannover 30625, Germany. Electronic address: charpentier@mpiib-berlin.mpg.de.
authors.forename: Emmanuelle
authors.initials: E
authors.lastname: Charpentier
authors.affiliation: Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Tel Aviv University, Tel Aviv 69978, Israel. Electronic address: ehudq@post.tau.ac.il.
authors.forename: Udi
authors.initials: U
authors.lastname: Qimron
mesh_terms: D056704:Adaptive Immunity / Q000235:genetics*; D001105:Archaea / Q000235:genetics / Q000276:immunology; D001419:Bacteria / Q000235:genetics / Q000276:immunology; D064113:CRISPR-Cas Systems / Q000235:genetics* / Q000276:immunology; D064112:Clustered Regularly Interspaced Short Palindromic Repeats / Q000235:genetics* / Q000276:immunology; D011387:Prokaryotic Cells / Q000276:immunology*