PiwiRDRP-DEPENDENTRNAi(NEMATODES,PROTOZOA,ANDPLANTS)RDRP-INDEPENDENTRNAi(FLIESANDMAMMALS)NUCLEARRNAiCYTOPLASMNUCLEUSConvergentorbidirectionaltranscriptionTransinteractionofgeneandpseudogeneTransposonsorpseudogeneRNAderivedfromstructuredlociRITSRdp1RDRCDicerRNAPolIIHistonemodifcationandchromatinremodelinge.g.,Self-enforcingloop(S.pombe)3´end:trimmingandmethylation3´end:trimmingandmethylationTarget-dependentamplificationHistonemodifcationsandDNAeliminationOthermodelsofchromatinremodelingTranscriptionalsilencingorlicensingPiwiping-pongcyclee.g.,AmplificationofRNAibyRdRPsinnematodes:theERIPathwayRdRPRdRP1osiRNAsAlternativeRISCinput21U(piwi-like)miRNADirectsynthesisof2osiRNAsbyRdRPsdsRNAsynthesisbyRdRPfollowedbydicing2osiRNAsNaturalantisensetranscriptsSpecificmRNAsmRNAdegradationand/ortranslationsilencingPosttranscriptionalsilencingInvertedrepeats?Ago1opiRNAsSpecificmiRNAcanactasa1osiRNAandtriggerendoRNAi,e.g.,tasiRNApathwayLicensingargonauteSilencingargonauteORDicingDicingArgonauteDicerRISC(RNA-inducedsilencingcomplex)TranscriptionalsilencingInheritablemaintenanceofsilencingSelf/nonselfrecognitionHistonemodifcationand/orDNAmethylationSlicingofmRNAand/ordirectrecruitmentofRdRPsRRF-3DicingRRF-11osiRNA(26G)2osiRNA(22G)dsRNAtriggerproductionProductionof2osiRNAsRRF-1AgoAgoAgoAgoAgoAgoAgo1AgoPiwiPiwiPiwiAgo3Ago3Ago3Switchtocentromere-specifchistones442Cell150,July20,2012©2012ElsevierInc.DOI10.1016/j.cell.2012.07.006SnapShot:EndogenousRNAiPathwaysMathieuFlamandandThomasF.DuchaineGoodmanCancerResearchCentre,DepartmentofBiochemisty,McGillUniversity,Montreal,QuebecH3A1A3,CanadaSeeonlineversionforlegendandreferences.442.e1Cell150,July20,2012©2012ElsevierInc.DOI10.1016/j.cell.2012.07.006SnapShot:EndogenousRNAiPathwaysMathieuFlamandandThomasF.DuchaineGoodmanCancerResearchCentre,DepartmentofBiochemisty,McGillUniversity,Montreal,QuebecH3A1A3,CanadaEndogenousRNAi(endoRNAi)identifiesaheterologousbutinterrelatedarrayofsmallRNA-mediatedphenomenatriggeredbyanddirectingthesilencingof...
