简介:DNAbarcodingisapowerfulapproachforcharacterizingspeciesoforganisms,especiallythosewithalmostidenticalmorphologicalfeatures,therebyhelpingtotoestablishphylogeneticrelationshipsandrevealevolutionaryhistories.Inthisstudy,wechosea648-bpsegmentofthemitochondrialgene,cytochromecoxidasesubunit1(COI),asastandardbarcoderegiontoestablishphylogeneticrelation-shipsamongbrineshrimp(Artemia)speciesfrommajorhabitatsaroundtheworldandfurtherfocusedonthebiodiversityofArtemiaspeciesinChina,especiallyintheTibetanPlateau.SamplesfromfivemajorsaltlakesoftheTibetanPlateaulocatedataltitudesover4,000mshowedcleardifferencesfromotherArtemiapop-ulationsinChina.Wealsoobservedtwoconsistentaminoacidchanges,153A/Vand183L/F,intheCOIgenebetweenthehighandlowaltitudespeciesinChina.Moreover,indelsintheCOIsequencewereidentifiedincystandadultsamplesuniquetotheCoQenpopulationfromtheTibetanPlateau,demonstratingtheneedforadditionalinvestigationsofthemitochondrialgenomeamongTibetanArtemiapopulations.
简介:RecognitionofDNAdamageisacriticalstepforDNAdamage-mediatedcellularresponse.XPCisanimportantDNAdamagerecognitionproteininvolvedinnucleotideexcisionrepair(NER).WehavestudiedtheXPCproteinincisplatinDNAdamagingtreatment-mediatedcellularresponse.ComparisonofthemicroarraydatafrombothnormalandXPCdefectivehumanfibroblastsidentified861XPC-responsivegenesinthecisplatintreatment(withminimumfoldchange≥1.5).Thecellcycleandcellproliferation-relatedgenesarethemostaffectedgenesbytheXPCdefectinthetreatment.Manyothercellularfunctiongenes,especiallytheDNArepairandsignaltransduction-relatedgenes,werealsoaffectedbytheXPCdefectinthetreatment.Tovalidatethemicroarraydata,thetranscriptionlevelsofsomemicroarray-identifiedgeneswerealsodeterminedbyanRT-PCRbasedrealtimePCRassay.TherealtimePCRresultsareconsistentwiththemicroarraydataformostofthetestedgenes,indicatingthereliabilityofthemicroarraydata.Tofurthervalidatethemicroarraydata,thecisplatintreatment-mediatedcaspase-3activationwasalsodetermined.TheWesternblothybridizationresultsindicatethattheXPCdefectgreatlyattenuatesthecisplatintreatment-mediatedCaspase-3activation.Weelucidatedtheroleofp53proteinintheXPCproteinDNAdamagerecognition-mediatedsignalingprocess.TheXPCdefectreducesthecisplatintreatment-mediatedp53response.TheseresultssuggestthattheXPCproteinplaysanimportantroleinthecisplatintreatment-mediatedcellularresponse.Itmayalsosuggestapossiblemechanismofcancercelldrugresistance.
简介:目的:观察不同训练强度对运动员血浆游离DNA(cf-DNA)的影响并探讨其可能机制,以期为运动训练负荷监控提供新型标志物。方法:60名田径运动员随机分为三组:低强度训练组,中强度训练组和高强度训练组,在标准400m跑道上,分别进行60%、75%和90%HRmax(最大心率)强度训练(跑步)20min,测定训练前后cf-DNA、外周血淋巴细胞凋亡率、淋巴细胞促凋亡因子(Bax)和抗凋亡因子(Bcl-2)蛋白的表达。结果:低强度训练组和中强度训练组各指标在训练前后均无显著性变化。高强度训练组训练后即刻,cf-DNA升高了110.0%(102.23±21.37pg/μLvs48.67±12.72pg/μL,P〈0.01),淋巴细胞凋亡率升高了72.5%(7.16±1.05%vs4.15±0.55%,P〈0.01),Bax/Bcl-2比值升高了82.6%(0.42±0.10vs0.23±0.07,P〈0.01)。结论:cf-DNA具有训练强度依赖性,可能是运动训练负荷监控与组织损伤早期、敏感的新型标志物;外周血淋巴细胞凋亡参与了高强度训练后cf-DNA的升高。
简介:Mitoxantrone,aclinicallyusefulantitumourantibioticforleukaemiaandbreastcancer,hasreceivedmoreattentions.Inthispaper,theinteractionbetweenmitoxantroneandcalfthymusDNAisinvestigatedbyRamanandfluorescencespectroscopies,andthebindingsiteofmitoxantronetocalfthymusDNAisexplored.TheresultsshowedthatmitoxantroneinteractswithcalfthymusDNAbasesbytheintercalationofanthracyclineintothebasepairplaneofadenine(A)andthymine(T),anditresultsinthedisruptionofthehydrogenbondsbetweencalfthymusDNAbases,andthusthecalfthymusDNAdouble-strandcanbedisruptedintotheB-formDNAdouble-strandsegments.
简介:本文提出DNA序列相似度指标,建立DNA序列比对算法。首先,将水生生物DNA样本序列与现有的基因库中的DNA序列逐项比对;其次,在满足特定阈值条件下,确认样本序列的分类。利用Java编程语言来实现算法,通过MonteCarlo模拟和实际应用,验证算法的有效性。理论结果表明:在满足特定阈值条件下,通过计算DNA序列相似度,能够确定数据库中与未知DNA样本序列最相似的序列,判断样本序列的分类。模拟实验、对比研究和应用结果表明:相似度指标算法在有效判别DNA序列的分类,提高DNA序列匹配成功率,降低程序复杂度等方面具有优良特征。
简介:目前关于落叶木本果树DNA提取的材料多数为植物的叶片,叶片具有试材广泛、容易研磨、DNA产量高、质量好等优点,但也会受到季节、病虫害的影响且不耐贮藏。落叶果树枝条具有取材容易、DNA含量丰富的特点而适合在休眠季节用于提取DNA,进而加速果树分子生物学研究进程。本研究探讨了CTAB法、SDS法对休眠季节不同时期取材的葡萄、桃、樱桃、杏、苹果、银杏、柿子、枣8种落叶果树的一年生枝条DNA提取效果。结果表明:除葡萄外其他多数材料在整个休眠时期均能提出高质量的DNA,所提DNA电泳带纹清晰、亮度高,DNA产率高、质量优,可用于有关分子生物学的后续试验(RAPD分析);再DNA提取方法方面,从DNA产量和质量上来看,SDS法总体上要优于CTAB法。最后对提取中出现中存在过多的酚类、多糖和其他次生物质去除方法进行了讨论。