RNA提取纯化试剂

Rules of siRNA design for RNA interference (RNAi)

SiRNA产品介绍:

  • siRNA库:超过10000种基因的SiRNA库,拿来就用!
  • siRNA技术相关试剂
    siRNA|反义寡核苷酸|RNAiOligo合成|RNAi定量|RNAi文库|miRNA分离|miRNA分析|siRNA酶|siRNA标记|siRNA纯化|siRNA合成|siRNA载体|siRNA转录|siRNA转染|siRNA构建试剂盒|其它
  • siRNA表达载体
  • siRNA载体构建服务
  • siRNA
  • DNA/有机/多肽合成

================  蚂蚁淘在线  ================

免责声明:本文仅代表作者个人观点,与本网无关。其创作性以及文中陈述文字和内容未经本站证实,对本文以及其中全部或者部分内容、文字的真实性、完整性、及时性本站不做任何保证或承诺,请读者仅作参考,并请自行核实相关内容

版权声明:未经蚂蚁淘在线授权不得转载、摘编或利用其他方式使用上述作品。已经经本网授权使用作品的,应该授权范围内使用,并注明“来源:蚂蚁淘在线”。违反上述声明者,本网将追究其相关法律责任。

  • 资质认证

    获得国家资质,权威认证!

  • 全国联保

    全国联保,官方无忧售后

  • 正规发票

    正规发票,放心购买

  • 签订合同

    签订合同,保障您的权益

/**/
Source:ProtocolOnline
Abstract:SummarizebothTomTuschl"smotifsiRNAdesignrulesandsiRNArationaldesign.

GeneralGuidelines

  1. siRNAtargetedsequenceisusually21ntinlength.
  2. Avoidregionswithin50-100bpofthestartcodonandtheterminationcodon
  3. Avoidintronregions
  4. Avoidstretchesof4ormorebasessuchasAAAA,CCCC
  5. AvoidregionswithGCcontent<30%or>60%.
  6. Avoidrepeatsandlowcomplexsequence
  7. Avoidsinglenucleotidepolymorphism(SNP)sites
  8. PerformBLASThomologysearchtoavoidoff-targeteffectsonothergenesorsequences
  9. AlwaysdesignnegativecontrolsbyscramblingtargetedsiRNAsequence.ThecontrolRNAshouldhavethesamelengthandnucleotidecompositionasthesiRNAbuthaveatleast4-5basesmismatchedtothesiRNA.Makesurethescramblingwillnotcreatenewhomologytoothergenes.

TomTuschl"srules

  1. SelecttargetedregionfromagivenCDNAsequencebeginning50-100ntdownstreamofstartcondon
  2. Firstsearchfor23-ntsequencemotifAA(N19).Ifnosuitablesequenceisfound,then,
  3. Searchfor23-ntsequencemotifNA(N21)andconvertthe3"endofthesensesiRNAtoTT
  4. OrsearchforNAR(N17)YNN
  5. TargetsequenceshouldhaveaGCcontentofaround50%

A=Adenine;T=Thymine;R=AdenineorGuanine(Purines);Y=ThymineorCytosine(Pyrimidines);N=Any.

RationalsiRNAdesign

Byexperimentallyanalyzingthesilencingefficiencyof180siRNAstargetingthemRNAoftwogenesandcorrelatingitwithvarioussequencefeaturesofindividualsiRNAs,ReynoldsetalatDharmacon,IncidentifiedeightcharacteristicsassociatedwithsiRNAfunctionality.ThesecharacteristicsareusedbyrationalsiRNAdesignalgorithmtoevaluatepotentialtargetedsequencesandassignscorestothem.SequenceswithhigherscoreswillhavehigherchanceofsuccessinRNAi.Thetablebelowliststhe8criteriaandthemethodsofscoreassignment.

Criteria

Description

Score

Yes

No

1

Moderatetolow(30%-52%)GCContent

1point

2

Atleast3A/Usatpositions15-19(sense)

1point/perAorU

3

Lackofinternalrepeats(Tm*<20¡ãC)

1point

4

Aatposition19(sense)

1point

5

Aatposition3(sense)

1point

6

Uatposition10(sense)

1point

7

NoG/Catposition19(sense)

-1point

8

NoGatposition13(sense)

-1point

Asumscoreof6definesthecutoffforselectingsiRNAs.AllsiRNAsscoringhigherthan6areacceptablecandidates.

*Tm=79.8+18.5*log10([Na+])+(58.4*GC%/100)+(11.8*(GC%/100)2)-(820/Length)

Forexample,theTmcanbecalculatedasfollowsforthesiRNAUUCUCCAGCUUCUAAAAUA

Tm=79.8+18.5*log10(0.05)+(58.4*31.6/100)+(11.8*(31.6/100)2)-(820/19)

Tm=32.19

TherearetwosiRNAdesigntoolswhichimplementthissiRNAdesignalgorithm:oneisofferedbyDharmacon,Inc;theotherisadownloadableExceltemplate,writtenbyMauriceHoathttp://boz094.ust.hk/RNAi/siRNA.References

  1. ElbashirSMetal.(2001)Duplexesof21-nucleotideRNAsmediateRNAinterferenceinculturedmammaliancells.Nature.411:494-498.
  2. ElbahirSMetal.(2001).FunctionalanatomyofsiRNAsformediatingefficientRNAiinDrosophilamelanogasterembryolysate.EMBOJ.20:6877-6888.
  3. ElbashirSMetal.(2002).AnalysisofgenefunctioninsomaticmammaliancellsusingsmallinterferingRNAs.Methods.26:199-213.
  4. ReynoldsA,LeakeD,BoeseQ,ScaringeS,MarshallWS,KhvorovaA.RationalsiRNAdesignforRNAinterference.NatBiotechnol.2004Mar;22(3):326-30.
  5. http://www.basic.northwestern.edu/biotools/oligocalc.html
  6. http://boz094.ust.hk/RNAi/siRNA