分子整合.docx

分子整合.docx

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分子整合

名词解释

Alufamily：

AdispersedintermediatelyrepetitiveDNAsequencefoundinthehumangenomeinaboutthreehundredthousandcopies.Thesequenceisabout300bplong.ThenameAlucomesfromtherestrictionendonucleaseAluIthatcleavesit.

Ac-Ds：

Thebestcharacterizedmaize（玉米）Tnelementisa4.5KbelementcalledAc（foractivator,autonomous,havetheabilitytotranspose.）,Ds（fordissociation,nonautonomous,defectiveversionsofAc）.

APendonuclease（无碱基内切酶）:

endonucleasethatinitiatesexcisionrepairatapurinicandapyrimidinicsitesonDNA.

Aminoacyl-tRNAsynthetase（氨酰基tRNA合成酶）:

氨酰基-tRNA合成酶（ARS）catalyzesthebondingbetweenspecifictRNAsandtheaminoacids.

Antisensestrand（反义链）:

thesecondstrandiscalledtheantisensestrandbecauseitssequenceofnucleotidesisthecomplementofmessagesense.

Asite:

Effectofacyl-tRNAbindingsites,mainlyinthelargesubunit,LSU.

Autogenousregulation:

Autogenousregulationisageneralstrategyofbalancingribosomalproteinsynthesisinbacteria.

Attenuator（弱化子）:

Anattenuatorisaterminatorsequenceatwhichattenuationoccurs..

AntisenseRNA:

Itisasingle-strandedRNAthatiscomplementarytoamessengerRNA（mRNA）strandtranscribedwithinacell.

Alternativesplicing（选择性剪接）:

Removalofintronsand/orexonsfromaprimarymRNAtranscriptinmultiplepatterns,generatingmorethanonetypeofmRNAfortranslation.

Bidirectionalreplication（双向复制）：

DNA的复制方式之一。

从复制泡开始两个复制叉按相反方向推移完成复制。

Base-excisionrepair（碱基切除修复）:

Cvalue：

TheamountDNAfoundinhaploidgenome,measuredinmillionbasepairsorinpg.

Cvalueparadox：

describesthelackofrelationshipbetweentheDNAcontent（C-value）ofanorganismanditscodingpotential.

Corepromoter：

NeededtoensurenormalRNApolymeraseIItranscriptionstarting,minimalDNAsequences,includingtranscriptionstartsitesandtranscriptioninitiationsitesupstreamTATAzone.

CAATbox：

CAATboxupstream4.transcriptionstartpoints-75bp,consensussequenceisGGCC/TCAATCT,,namedfortheconservedsequenceofCAAT.

Cappingenzyme：

RNA鸟苷酸基转移酶=戴帽酶（Cappingenzyme）.

Chaperones（分子伴侣）areaclassofproteinswhichbindtoincompletelyfoldedorassembledproteinsinordertoassisttheirfoldingorpreventthemfromaggregating.

Constitutivegene（组成型基因）:

Aconstitutivegeneisagenethatistranscribedcontinuallyasopposedtoafacultativegenewhichisonlytranscribedwhenneeded.

CAP-cAMPbindingsite:

Corepressor:

acorepressorisasubstancethatinhibitstheexpressionofgenes.

Cis-actingelement（顺式作用元件）:

LocatedintheregulatedupstreamanddownstreamofDNAcodedsegments,canaffecttheactivityofitsowngeneexpressionDNAsequence.GeneexpressionandregulationrelatingtotheCIS-actingelementsmainpromoter,enhancer,andsilence.

DNADouble–helixmodel：

Twoantiparallelnucleotidechainintertwinedtoformaright-handeddoublehelicalstructure.

Denaturation：

Atransitionfromthenativetothedenaturedstateiscalleddenaturation.DenaturedDNAissinglestranded.

DNAfingerprinting（DNA指纹）：

DNAfingerprintinganalyzesthedifferencesbetweenindividualsofthefragmentsgeneratedbyusingrestrictionenzymestocleaveregionsthatcontainshortrepeatedsequences.Becausetheseareuniquetoeveryindividual,thepresenceofaparticularsubsetinanytwoindividualscanbeusedtodefinetheircommoninheritance.

D-loopreplication：

LocatedintheregulatedupstreamanddownstreamofDNAcodedsegments,canaffecttheactivityofitsowngeneexpressionDNAsequence.GeneexpressionandregulationrelatingtotheCIS-actingelementsmainpromoter,enhancer,andsilence.

DNAdamage（DNA损伤）:

Degeneracy（密码的简并性）:

Thepresenceinthegeneticcodeofmorethanonecodonforthesameaminoacid.

DNAmethylation（DNA甲基化）:

Catalyzedbymethyltransferase,CGtwonucleotidesofDNAcytosineareselectivelyaddedmethyl,theformationof5-methylcytosine,thiscommongenesequenceof5'-CG-3'.

DNaseIhypersensitivesite（DNaseI高敏的位点）:

Inactivelytranscribedregions,theDNAfragmentsofcarefullyisolatedchromatinarehaveanespeciallyhighsensitivitytoDNaseI,referredtoashypersensitivesites.

Error-pronerepair:

Exon：

ItisanysegmentofaninterruptedgenethatisrepresentedinthematureRNAproduct.

EF-Tu（热不稳定延伸因子）:

Aminoacylasemediated-tRNAenterstheRibosomeabitblank.

EFTu-EFTscycle（EFTu-EFTs循环）:

EF-G（延伸因子G）:

Withtranspositionofenzymeactivity,bythehydrolysisofGTP,theRibosomemovesalongthemRNAdownacodon,catalyticribosomalpeptiden--tRNAintothepbitinabit,onceagain,abitempty.

Esite:

Epigenetics（表观遗传学）:

Duetonon-basesequencechanges,suchasDNAmethylationandchromatinconformationchangesleadtochangesingeneexpression,affectingorchangingthegene'sfunctionanddevelopmentofindividuals,andinheritancetofuturegenerations.

Enhancer:

anEnhancerisashortregionofDNAthatcanbindproteinscalledanactivator.

Genome：

Thegenomeisthecompletesetofsequencesinthegeneticmaterialofanorganism.ItincludesthesequenceofeachchromosomeplusanyDNAinorganelles.

Gene：

unitofinformationthatisencodedinaspecificnucleotidesequenceinonestrandofDNA

Genefamily：

consistsofasetofgeneswhoseexonsarerelated;thememberswerederivedbyduplicationandvariationfromsomeancestralgene.

Gyrase（旋转酶）：

Isatwo-GraAandGraBtwoproteinsubunitsofthetetramer,DNAgyraseitcanusetheenergyofATPbindingandhydrolysistonegativehyper-mediatedrelaxationofspiraltoCovalentclosedDNAisknowntoalloftopoisomerase.

Generalorbasalfactors（通用转录因子,或基本转录因子、普遍转录因子）：

ForallrequiredforRNApolymeraseIItranscriptioninitiation,transcriptionstartingpointsaroundtheformationstartingcompoundandRNApolymeraseII,andassistindeterminingthestartingpoint

GroupIintron：

arelargeself-splicingribozymes.TheycatalyzetheirownexcisionfrommRNA,tRNAandrRNAprecursorsinawiderangeoforganisms.

Geneamplification（基因放大）:

Aprocessinacellbywhichaparticulargeneisreplicatedsothatmorecopiesareavailabletoproduceaproteinforthecell'suse.

Generearrangement（基因重排）:

Bygenetransfer,DNA,suchasbreakingthenormalgenesequencewrongchange.

HyperchromicityofDNA（DNA的增色效应）：

Helicase（解旋酶）：

Usuallyfluidproteinring,throughtheenergyofATPhydrolysisbythehelicaseloadermountedonDNAsinglestrand（singlechainpassingthroughCentral）,3'--5'or5'--3'directionofpolarity,polaritythepolarityisitscombinationofasinglechain.Aseasyit'slikeDNApolymerase.

HeterogeneousnuclearRNA：

AdiverseassortmentofRNAtypesfoundinthenucleus,includingmRNAprecursors（pre-mRNA）andothertypesofRNA.AbbreviatedhnRNA.

Housekeepinggene（管家基因）:

Ageneinvolvedinbasicfunctionsneededforthesustenanceofthecell.Housekeepinggenesareconstitutivelyexpressed.

Histoneacetylation（组蛋白乙酰化）:

AcetylationofthelysineresiduesattheNterminusofhistoneproteinsremovespositivecharges,therebyreducingtheaffinitybetweenhistonesandDNA。

HMG（High-mobility-group高迁移率组）:

Highmobilitygroup（HMG）proteinsareafamilyofrelativelylowmolecularweightnon-histonecomponentsinchromatin.HMGisagroupofchromosomalproteinsthathelpwithtranscription。

Helix-turn-helix:

ThistypeofproteinmoleculeswithatleasttwoAlphaHelix,formedbytheshortside-chainaminoacidresiduesintheMiddle"aturningpoint".

Itconsistsoftwosegmentsofalphahelixseparatedbyashortirregularregion,or"turn".ThemoreC-terminalhelixliesinthemajorgrooveoftheDNAdoublehelix.ContactsbetweentheaminoacidR-groupsofthishelixandthenucleotidesofthegroovedeterminethesequencespecificityoftheDNAbinding.

Homeodomain（同源域）:

Isinthehomeoticgenes（homeoticgene）hasbeenreferredtoby180nucleotidesencode60aminoacidsequence,composedoftheaminoacidsinapeptideisconservativeinevolution,fromfruitfliesandmicetolittlechange.180nucleotidesencodehomologousdomainsareusuallylocatedinExongenecharacterization.Homologousdomainsplayaroleoftranscriptionfactors.

HRE（激素应答元件）:

AnHREisacis-regulatoryDNAsequenceforahormonethatactsbybindingtoareceptorthatcanactasatranscriptionfactor;thatisabindingsiteforthehormone-receptorcomplex。

Heat-shockresponseelement（热休克应答元件）:

ThenucleotideSequence,CNNGAANNTCCNG,whichisinthepromoterregionoftheheat-shockgenes.Whentheanimalisexposedtocertaintypesofstresssuchasasuddenriseintemperature,thefirstthingthathappenstoactivatethesegenesisthebindingoftheHSEbyatranscriptionalenhancerprotein.

Heatshockfactor（热休克因子）:

Heatshockfactorisakeyfactorofheatshockgenetranscriptionregulationofeukaryoticcells,instressandundernormalphysiologicalconditionsplayanimportantrole.

Invertedrepeat：

InDNAinvertedrepetitionsofbasesequencewithtwofoldsymmetryoccurringovertwostrandsofDNA.

IS（insertedsequences）element：

ISareexamplesofrelativelysimpletransposableelements.Theycontainterminalinvertedrepeatsandeachencodesa"specificlocation"transposase.

Intron：

ItisasegmentofDNAthatistranscribed,butremovedfromwithinthetranscriptbysplicingtogetherthesequences（exons）oneithersideofit.

IsoacceptingtRNAs（同工tRNA）:

CarrythesameAAandtheanticodondifferentsetoftRNAiscalledwiththetRNA.WithagroupbythesameaminoacyltRNAsynthesisof-tRNAcatalyzedbyenzymesandcarryAA.

Inducibleoperon（可诱导的操纵子）:

Insulator（绝缘子）:

Itisasequencethatpreventsanactivatingorinactivatingeffectpassingfromonesidetotheother.

IRE（铁应答元件）:

isashortconservedstem-loopwhichisboundbyironresponse-bindingproteins.

Klenowfragment（克列诺片段）：

DNA聚合酶的羧基大片段。

已丧失5'→3'端外切核酸酶活性，但仍保留5'→3'端聚合酶活性和3'→5'端