title: In defense of phage: viral suppressors of CRISPR-mediated adaptive immunity in bacteria.
abstract: Viruses that infect bacteria are the most abundant biological agents on the planet and bacteria have evolved diverse defense mechanisms to combat these genetic parasites. One of these bacterial defense systems relies on a repetitive locus, referred to as a CRISPR (clusters of regularly interspaced short palindromic repeats). Bacteria and archaea acquire resistance to invading viruses and plasmids by integrating short fragments of foreign nucleic acids at one end of the CRISPR locus. CRISPR loci are transcribed and the long primary CRISPR transcript is processed into a library of small RNAs that guide the immune system to invading nucleic acids, which are subsequently degraded by dedicated nucleases. However, the development of CRISPR-mediated immune systems has not eradicated phages, suggesting that viruses have evolved mechanisms to subvert CRISPR-mediated protection. Recently, Bondy-Denomy and colleagues discovered several phage-encoded anti-CRISPR proteins that offer new insight into the ongoing molecular arms race between viral parasites and the immune systems of their hosts.
authors: Department of Immunology and Infectious Diseases, Montana State University, Bozeman, MT, USA. bwiedenheft@gmail.com
authors: Blake
authors: B
authors: Wiedenheft
mesh_terms: D056704:Adaptive Immunity; D001105:Archaea / Q000235:genetics* / Q000276:immunology / Q000821:virology*; D023641:Archaeal Viruses / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D001419:Bacteria / Q000235:genetics / Q000276:immunology / Q000821:virology*; D001435:Bacteriophages / Q000235:genetics* / Q000378:metabolism*; D064112:Clustered Regularly Interspaced Short Palindromic Repeats; D024881:Drug Resistance, Bacterial; D010957:Plasmids; D019642:RNA, Archaeal / Q000235:genetics; D012329:RNA, Bacterial / Q000235:genetics; D014764:Viral Proteins / Q000235:genetics* / Q000502:physiology*
chemical_list: D019642:RNA, Archaeal; D012329:RNA, Bacterial; D014764:Viral Proteins
references: Trends Plant Sci. 2011 May;16(5):265-72
references: 21439890
references: Nature. 2001 Jan 18;409(6818):363-6
references: 11201747
references: Science. 2008 May 23;320(5879):1047-50
references: 18497291
references: Nature. 2012 Feb 15;482(7385):331-8
references: 22337052
references: Cell. 2009 Nov 25;139(5):863-5
references: 19945373
references: PLoS Genet. 2010 Oct 28;6(10):e1001171
references: 21060859
references: Nature. 2011 Sep 21;477(7365):486-489
references: 21938068
references: Proc Natl Acad Sci U S A. 2011 Jun 21;108(25):10092-7
references: 21536913
references: EMBO J. 2006 Jun 21;25(12):2768-80
references: 16724105
references: Trends Microbiol. 2011 Jun;19(6):286-94
references: 21531564
references: Nat Rev Microbiol. 2011 Jun;9(6):467-77
references: 21552286
references: Philos Trans R Soc Lond B Biol Sci. 2009 Jan 12;364(1513):99-115
references: 18926973
references: J Biol Chem. 2011 Jun 17;286(24):21643-56
references: 21507944
references: Mol Cell. 2012 Feb 10;45(3):303-13
references: 22227115
references: J Bacteriol. 2008 Feb;190(4):1390-400
references: 18065545
references: J Bacteriol. 2012 Nov;194(21):5728-38
references: 22885297
references: Cell Host Microbe. 2010 Jul 22;8(1):12-5
references: 20638637
references: Genes Dev. 2010 May;24(9):853-6
references: 20439425
references: Science. 2006 Jan 13;311(5758):195-8
references: 16410517
references: Annu Rev Genet. 2012;46:311-39
references: 23145983
references: Front Microbiol. 2012 Jul 19;3:238
references: 22833738
references: Nat Rev Genet. 2010 Mar;11(3):181-90
references: 20125085
references: Nature. 2001 Jun 14;411(6839):834-42
references: 11459066
references: Curr Biol. 2007 Sep 18;17(18):R789-93
references: 17878043
references: Proc Natl Acad Sci U S A. 2011 Jun 21;108(25):10098-103
references: 21646539
references: Nature. 2013 Jan 17;493(7432):429-32
references: 23242138
references: Biol Direct. 2006 Mar 16;1:7
references: 16545108
references: PLoS Comput Biol. 2012;8(4):e1002475
references: 22532794
references: Annu Rev Genet. 2011;45:273-97
references: 22060043
references: PLoS Comput Biol. 2005 Nov;1(6):e60
references: 16292354
references: Nat Rev Microbiol. 2009 Nov;7(11):828-36
references: 19834481
references: Nature. 2010 Nov 4;468(7320):67-71
references: 21048762
references: Trends Biotechnol. 2006 Apr;24(4):186-93
references: 16503061
references: Science. 2012 Aug 17;337(6096):816-21
references: 22745249
references: Cell. 2007 Aug 10;130(3):413-26
references: 17693253
references: Nature. 2009 Jan 22;457(7228):405-12
references: 19158786
references: Cell. 2009 Nov 25;139(5):945-56
references: 19945378
references: Trends Biochem Sci. 2009 Aug;34(8):401-7
references: 19646880
references: Nat Rev Microbiol. 2010 May;8(5):317-27
references: 20348932