sisterchroatidhesionisessentialforroerchroososegregationandfaithfultransission
ofthegenodurgthecellcycle(oralesandlosada，2018uhlann，2016)fairetoestab
lishorresolvehesionatilyannerleadstogenoicstabilityandaneuloidysisterchro
atidhesionisdiatedbyhes，argshaedataseachethatnsistsofsc1a，
sc3，rad21，andeitherstag1orstag2huansoaticcells(haarhuisetal，2014
losadaandhirano，2005nasythandhaerg，2009onal，2008etersetal，2008
zhengandyu，2015)hesrgsologicallyentradnatogeneratehysicallkages
betatidsandenablehesionhesregutesotherchroosobasedro
cesses，suchasdnareair，transcrition，andchroosofoldg(rkenschgerandodo，
2013wuandyu，2012)theseotherfunctionsofheslikelyalsovolvetheologicalentra
ntofchroososorossiblytheextrionofdnaloos(barrgtoal，2017
davidsoal，2016haarhuisetal，2017)
hesisloadedontochroosostelohaseandg1bythes24lex(niblau2
huans)(ciosketal，2000gillesieandhirano，2hietal，2004tonketal，
2004osoboundhesisdynaicand
isactivelyreovedfrochroososbythehesreleasgfactroteds5aords5b(chaal，2012kuengetal，2006loezserraetal，
2013ouyangandyu，2017ouyangetal，2013ouyangetal，2016)durgdnarelication
shase，aoolofhesisnvertedtothehesivefor，ddiatessisterchroatidhesion(gerlichetal，2006kuengetal，2006)huan
cells，hesionestablishntreirestheacetytionofsc3bytheacetyltransferaseses1and
es2andsubseentrecruitntofsoror，osos(aloretal，2017houandzou，2005nishiyaaetal，2010ouyangetal，
2016ranketal，2005rolefbenshaharetal，2008rowndetal，2009unaletal，2008
zhangetal，2008a)
thecheckotkaserotesc1andrad53arereired
thebuddgyeast，saharoycescerevisiae，toatacell
viabilitytheresenceofdrugscagdaagetodnaor
arrestofdnarelicationforks1±3itisthoughtthattheyactby
hibitgcellcyclerogression，allogtifordnareairto
takecec1andrad53alsoslo
resonsetodnaalkytion4，althoughthechanisforthis
anditsretiveiortancerotectgcellsfrodnadaage
havenotbeendeteredhereaalkytg
agentthylthanesulhonate(s)rofoundlyreducesthe
rateofdnarelicationforkrogressionho
doesnotreirerad53orc1theaeleratedshase
checkotutants4，therefore，isriarilyanseenceof
aroriateitiationevents5±7arelicationtheresenceofsntrast，
relicationforkscheckotutantslseirreversiblyat
highratesoreover，thecytotoxicityofscheckot
utantsourssecicallyageth，reventgdaageduced
dnarelicationforkcatastroheseestobeariarychanis
bytsreserveviabilitythefaceofdna
toensurethataletesetoftheeukaryoticgenois
reciselydulicateddurgtheliitederiodofshase
everycellcycle，dnarelicationitiatesatanuberof
relicationorigsonchroosos(gilbert，2001belland
dutta，2002)aseachchroosoregionrelicatesa
secificeriodgoforigactivation
tberegutedalthoughgunderstandg
ofrotefactorsvolveditiationandelongationof
re
第180章 发错分卷，勿订[1/2页]