学科分类
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18 个结果
  • 简介:G-proteincoupledreceptors(GPCRs)representoneofthemostimportantclassesofdrugtargetsforpharmaceuticalindustryandplayimportantrolesincellularsignaltransduction.PredictingthecouplingspecificityofGPCRstoG-proteinsisvitalforfurtherunderstandingthemechanismofsignaltransductionandthefunctionofthereceptorswithinacell,whichcanprovidenewcluesforpharmaceuticalresearchanddevelopment.Inthisstudy,thefeaturesofaminoacidcompositionsandphysiochemicalpropertiesofthefull-lengthGPCRsequenceshavebeenanalyzedandextracted.Basedonthesefeatures,classifiershavebeendevelopedtopredictthecouplingspecificityofGPCRstoG-proteinsusingsupportvectormachines.Thetestingresultsshowthatthismethodcouldobtainbetterpredictionaccuracy.

  • 标签: G-蛋白 疾病预防 分子机制 临床表现
  • 简介:东方田鼠(Microtusfortis)分布于我国东北、西北、华中、华南17个省区,在韩国及俄罗斯也见报道.国内对该鼠的5个亚种,即指名亚种(M.f.fortis)(西北)、东北亚种(M.f.pelliecus)、辽宁亚种(M.f.dolichocephalus)、长江亚种(M.f.calamorum)和福建亚种(M.f.fujianensis)(华南),作过一般生物学描述[1],对于东方田鼠研究得较多的是长江亚种,60年代有人对该种动物的生态学特点进行了报道,近期对洞庭湖区东方田鼠的种群动态、繁殖特性、迁移行为也有系列研究[2],特别是该种动物具有对日本血吸虫天然抗感染性,引起了学术界的广泛兴趣,本研究通过对人工繁殖的东方田鼠的细胞遗传学的观察,了解该种动物的染色体数目的范围、染色体核型以及染色体G带特征.

  • 标签: 东方田鼠 系列研究 华中 抗感染 日本血吸虫 染色体核型
  • 简介:Microarrayhasbecomeapopularbiotechnologyinbiologicalandmedicalresearch.However,systematicandstochasticvariabilitiesinmicroarraydataareexpectedandunavoidable,resultingintheproblemthattherawmeasurementshaveinherent"noise"withinmicroarrayexperiments.Currently,logarithmicratiosareusuallyanalyzedbyvariousclusteringmethodsdirectly,whichmayintroducebiasinterpretationinidentifyinggroupsofgenesorsamples.Inthispaper,astatisticalmethodbasedonmixedmodelapproacheswasproposedformicroarraydataclusteranalysis.TheunderlyingrationaleofthismethodistopartitiontheobservedtotalgeneexpressionlevelintovariousvariationscausedbydifferentfactorsusinganANOVAmodel,andtopredictthedifferentialeffectsofGV(genebyvariety)interactionusingtheadjustedunbiasedprediction(AUP)method.ThepredictedGVinteractioneffectscanthenbeusedastheinputsofclusteranalysis.Weillustratedtheapplicationofourmethodwithageneexpressiondatasetandelucidatedtheutilityofourapproachusinganexternalvalidation.

  • 标签: 聚类基因 基因表达 微分结构 互感作用 基因多样性
  • 简介:Annotationsofcompletegenomesequencessubmitteddirectlyfromsequencingprojectsarediverseintermsofannotationstrategiesandupdatefrequencies.Theseinconsistenciesmakecomparativestudiesdifficult.Toallowrapiddataprepara-tionofalargenumberofcompletegenomes,automationandspeedareimpor-tantforgenomere-annotation.Hereweintroduceanopen-sourcerapidgenomere-annotationsoftwaresystem,Restauro-G,specializedforbacterialgenomes.Restauro-Gre-annotatesagenomebysimilaritysearchesutilizingtheBLAST-LikeAlignmentTool,referringtoproteindatabasessuchasUniProtKB,NCBInr,NCBICOGs,Pfam,andPSORTb.Re-annotationbyRestauro-Gachievedover98%accuracyformostbacterialchromosomesincomparisonwiththeoriginalmanuallycuratedannotationofEMBLreleases.Restauro-GwasdevelopedinthegenericbioinformaticsworkbenchG-languageGenomeAnalysisEnvironmentandisdistributedathttp://restauro-g.iab.keio.ac.jp/undertheGNUGeneralPublicLicense.

  • 标签: 生物信息学 基因组学 基因分析 基因解释系统
  • 简介:比较HitrapG蛋白Sepharose亲和色谱系统对不同动物血清或腹水的纯化效果,为抗体纯化提供依据。结果显示,G蛋白对不同动物血清IgG吸附能力不同,体现在单位体积抗体回收量明显不同,这一特点与A蛋白亲和色谱系统相似。该方法简便快速,纯化抗体纯度高,免疫活性好,色谱柱可反复使用多次

  • 标签: G蛋白 A蛋白 亲和色谱法 抗体
  • 简介:heterotrimericguanine核苷酸绑定蛋白质(G蛋白质)被表明了各种各样的发信号调停在植物的小径。然而,它在发信号的phytochromeA(phyA)的角色留下逃犯。在这研究,我们发现新调停phyA的显型指明了far-red照耀(FR)preconditioned房间死亡,它仅仅在跟随暴露到白光(WL)的FR-grown幼苗的胚轴发生。房间死亡在G变异的gpa1被减轻,但是与野类型(WT)比较在G变异的agb1加重了,在调停phyA的房间死亡小径的GPA1和AGB1的对抗角色的陈述语气。进一步的调查显示nonphotoconvertibleprotochlorophyllide(Pchlide633)的导致FR的累积,在暴露上产生反应的氧种类(ROS)到WL,为前提FR的房间死亡被要求。而且,ROS主要在叶绿体被检测用荧光灯探查。有趣地,到黑暗成年的幼苗的H2O2的申请导致类似于前提FR的房间死亡的显型。这表明ROS是为房间死亡的一个批评调停人。另外,我们观察到agb1比WT幼苗对H2O2更敏感,显示G蛋白质可以也修改到ROS应力的幼苗的敏感。一起拿这些结果,我们推断G蛋白质可以涉及表明小径调整Arabidopsis胚轴的前提FR的房间死亡的phyA。在phyA位于G蛋白质的参与下面发信号的可能的机制在这研究被讨论。

  • 标签: 细胞死亡 植物色素A 鸟嘌呤 胚轴
  • 简介:Thestudyofsmalldrugmoleculesinteractingwithnucleicacidsisanareaofintenseresearchthathasparticularrelevanceinourunderstandingofrelativemechanisminchemotherapeuticapplicationsandtheassociationbetweengenetics(includingsequencevariation)anddrugresponse.Inthiscontribution,wedemonstratehowthesequence-specificbindingofananticancerdrugDacarbazine(DTIC)tosinglebase(A-G)mismatchcouldbesensitivelydetectedbycombiningelectrochemicaldetectionwithbiosensingsurfacebasedongoldnanoparticles.

  • 标签: 电气化学 A-G基因 基因错配 抗癌药物 药物反应 纳米微粒
  • 简介:UnderstandingthecouplingspecificitybetweenGprotein-coupledreceptors(GPCRs)andspecificclassesofGproteinsisimportantforfurtherelucidationofreceptorfunctionswithinacell.IncreasinginformationonGPCRsequencesandtheGproteinfamilywouldfacilitatepredictionofthecouplingpropertiesofGPCRs.Inthisstudy,wedescribeanovelapproachforpredictingthecouplingspecificitybetweenGPCRsandGproteins.ThismethodusesnotonlyGPCRsequencesbutalsothefunctionalknowledgegeneratedbynaturallanguagepro-cessing,andcanachieve92.2%predictionaccuracybyusingtheC4.5algorithm.Furthermore,rulesrelatedtoGPCR-Gproteincouplingaregenerated.Thecom-binationofsequenceanalysisandtextminingimprovesthepredictionaccuracyforGPCR-Gproteincouplingspecificity,andalsoprovidescluesforunderstandingGPCRsignaling.

  • 标签: GPCR G蛋白 耦合特异性 预测 序列特征 生物机能
  • 简介:AcomputationalsystemforthepredictionandclassificationofhumanG-proteincoupledreceptors(GPCRs)hasbeendevelopedbasedonthesupportvectormachine(SVM)methodandproteinsequenceinformation.ThefeaturevectorsusedtodeveloptheSVMpredictionmodelsconsistofstatisticallysignificantfeaturesselectedfromsingleaminoacid,dipeptide,andtripeptidecompositionsofproteinsequences.Furthermore,thelengthdistributiondifferencebetweenGPCRsandnon-GPCRshasalsobeenexploitedtoimprovethepredictionperformance.ThetestingresultswithannotatedhumanproteinsequencesdemonstratethatthissystemcangetgoodperformanceforbothpredictionandclassificationofhumanGPCRs.

  • 标签: 疾病预防 识别方法 G-蛋白质 受体
  • 简介:G-proteincoupledreceptors(GPCRs)areaclassofseven-helixtransmembraneproteinsthathavebeenusedinbioinformaticsasthetargetstofacilitatedrugdiscoveryforhumandiseases.AlthoughthousandsofGPCRsequenceshavebeencollected,theligandspecificityofmanyGPCRsisstillunknownandonlyonecrystalstructureoftherhodopsin-likefamilyhasbeensolved.Therefore,identifyingGPCRtypesonlyfromsequencedatahasbecomeanimportantresearchissue.Inthisstudy,anoveltechniqueforidentifyingGPCRtypesbasedontheweightedLevenshteindistancebetweentworeceptorsequencesandthenearestneighbormethod(NNM)isintroduced,whichcandealwithreceptorsequenceswithdifferentlengthsdirectly.Inourexperimentsforclassifyingfourclasses(acetylcholine,adrenoceptor,dopamine,andserotonin)oftherhodopsin-likefamilyofGPCRs,theerrorratesfromtheleave-one-outprocedureandtheleave-half-outprocedurewere0.62%and1.24%,respectively.Theseresultsarepriortothoseofthecovariantdiscriminantalgorithm,thesupportvectormachinemethod,andtheNNMwithEuclideandistance.

  • 标签: G-蛋白 受体 遗传疾病 视紫红质
  • 简介:摘要目的:调查我院常用抗G^+致病菌的抗生素的种类效价情况,为抗G^+致病菌的合理用药提供依据。方法:从2978个样本中分离到953株G^+致病菌,用全自动微生物分析仪-VITEK32进行菌种鉴定及16种抗生素的药敏实验。结果:953株G^+致病菌经鉴定属于11大类,其中金黄色葡萄球菌、表皮葡萄球菌、溶血葡萄球菌、草绿色链球菌和肠球菌属是五类主要的G^+致病菌,依次分别占总分离量的30.3%、1713%、15.1%、9.8%和6.8%;在检测的16种抗生素对排在前五位的G.致病菌的平均效价最低的五类抗生素是:青霉素(24.22%)、红霉素(26.22%)、头孢唑林(28.06%)、与链霉素(30.52%)和庆大霉素(31.06%)。而抗口致病菌整体效果最好的是:螯合新泰林(93.72%)、万古霉素(82.62%)和四环素(78.68%)。结论:研究结果表明越来越多抗生素抗临床常见G^+致病菌的效价呈现逐年递减的趋势.

  • 标签: 抗生素 药物监测 耐药性 G^+致病菌
  • 简介:Werecentlyreportedtheuseofagene-trappingapproachtoisolatecellclonesinwhichareportergenehadintegratedintogenesmodulatedbyT-cellactivation.WehavenowtestedapanelofclonesfromthatreportandidentifiedtheonethatrespondstoavarietyofG-proteincoupledreceptors(GPCR).TheβlactamasetaggedEGR-3JurkatcellwasusedtodissectspecificGPCRsignalinginvivo.ThreeGPCRswerestudied,includingthechemokinereceptorCXCR4(Gicoupled)thatwasendogenouslyexpressed,theplateletactivationfactor(PAF)receptor(Gq-coupled),andβ2adrenergicreceptor(Gs-coupled)thatwasbothstablytransfected.Agonistsforeachreceptoractivatedtranscriptionoftheβ-lactamasetaggedEGR-3gene.InductionofEGR-3throughCXCR4wasblockedbypertussistoxinandPD58059,aspecificinhibitorofMEK(MAPK/ERKkinase).NeitheroftheseinhibitorsblockedisoproterenolorPAF-mediatedactivationofEGR-3.Conversely,β2-andPAF-mediatedEGR-3activationwasblockedbythep38,specificinhibitorSB580.Inaddition,bothβ2-andPAF-mediatedEGR-3activationcouldbesynergisticallyactivatedbyCXCR4activation.ThiscombinedresultindicatesthatEGR-3canbeactivatedthroughdistinctsignaltransductionpathwaysbydifferentGPCRsandthatsignalscanbeintegratedandamplifiedtoefficientlytunethelevelofactivation.

  • 标签: G-蛋白相连受体 信号通道 转移因子 EGR-3
  • 简介:目的:探讨UCP2-866G/A和ADIPOQ+45T/G基因多态性的交互作用与2型糖尿病合并冠心病发病风险的关系。方法:随机选取2014年10月至2015年5月在佳木斯大学附属第一医院就诊的130例单纯2型糖尿病患者和128例2型糖尿病合并冠心病患者进行病例对照研究。分别采用聚合酶链反应-限制性片段长度多态性(PCR-RFLP)方法和聚合酶链反应-高分辨率溶解曲线(PCR-HRM)方法检测UCP2-866G/A和ADIPOQ+45T/G的基因多态性,并用非条件Logistic回归分析两基因间的交互作用。结果:在两组间分别进行UCP2-866G/A和ADIPOQ+45T/G基因多态性的单独关联分析,两变异位点的基因型和等位基因的频率在两组间的分布及遗传模型关联分析均无统计学差异(P〉0.05)。两变异位点联合分析发现,UCP2-866G/A的GG、GA分别和ADIPOQ+45T/G的TG在2型糖尿病合并冠心病中存在正向交互作用(P=0.000,ORI=OR(AB)/(ORA×ORB)=30.533/(0.549×0.116)〉1;P=0.007,ORI=OR(AB)/(ORA×ORB)=13.914/(0.525×0.116)〉1。结论:该研究显示:UCP2-866G/A和ADIPOQ+45T/G单一基因的多态性与2型糖尿病合并冠心病患病风险无关,而两者之间的交互作用可能增加2型糖尿病合并冠心病的发病风险。

  • 标签: UCP2 ADIPOQ 基因多态性 2型糖尿病 冠心病
  • 简介:Thenon-classicalHLAclassIantigenHLA-GisanimmunemodulatorwhichinhibitsthefunctionsofTcells,NKcells,andtheDendriticcells(DC).Asaresult,HLA-Gexpressioninmalignantcellsmayprovidethemwithamechanismtoescapetheimmunesurveillance.Inmelanoma,HLA-Gantigenexpressionhasbeenfoundin30%ofsurgicallyremovedlesionsbutinlessthan1%ofestablishedcelllines.OnepossiblemechanismunderlyingthedifferentialHLAGexpressioninvivoandinvitroisthattheHLA-Ggeneisepigeneticallyrepressedinmelanomacellsinvitro.Totestthishypothesis,wetreatedtheHLA-GnegativemelanomacelllineOCM-1AwiththeDNAmethyltransferaseinhibitor5-aza-2'-deoxycytidine(5-AC)andanalyzedwhetherHLA-Gexpressioncanberestored.OurdatastronglysuggestthatHLA-GissilencedasaresultofCpGhypermethylationwithina5'regulatoryregionencompassing220bpupstreamofthestartcodon.Aftertreatment,HLA-GmRNAexpressionwasdramaticallyincreased.WesternblotandflowcytometryshowedthatHLA-Gproteinwasinduced.Interestingly,HLA-Gcellsurfaceexpressiononthe5-ACtreatedOCM-1AcellsismuchlessthanthatontheHLA-GpositiveJEG-3cellswhileasimilaramountoftotalHLA-Gwasobserved.Possiblemechanismsforthedifferencewereanalyzedinthestudysuchascellcold-treatment,peptideloadingandantigenprocessingmachinerycomponents(APM)aswellasβ2microglobulin(β2-m)expression.DatarevealedthattheAPMcomponentcalreticulinmightbeinvolvedinthelowerHLA-GsurfaceexpressiononOCM-1Acells.Takentogether,ourresultsindicatedthatDNAmethylationisanimportantepigeneticmechanismbywhichHLA-Gantigenexpressionismodulatedinmelanomacellsinvitro.Furthermore,tothefirsttime,wehypothesizedthatthedeficiencyofcalreticulinmightbeinvolvedinthelowHLA-Gsurfaceexpressiononthe5-ACtreatedOCM-lAcells.

  • 标签: 感应现象 HLA-G 基因表达 黑色素瘤 肿瘤细胞 OCM-1A
  • 简介:目的探讨C57BL/6与ICR小鼠在博来霉素(BLM)致肺纤维化过程中的种属差异。方法8周龄雌性C57BL/6小鼠19只,ICR小鼠16只,分别经尾静脉一次性注射BLM150mg/kg,观察每组小鼠体重、生存率及肺组织病理改变。结果①C57BL/6与ICR小鼠最低体重分别发生在静脉注射处置后的7d和5d,最低体重分别为注射前的65.46%和73.21%,两组间无显著的统计学差异。②C57BL/6与ICR小鼠的生存率分别为36.84%和56.25%,两组间存在显著的统计学差异。③C57BL/6小鼠BLM注射后28d,在胸膜下及血管周围形成广泛、稳定的间质纤维化病理改变,而ICR小鼠肺组织未见明显纤维化形成。C57BL/6小鼠肺纤维化病理评分明显高于ICR小鼠(P〈0.001)。结论BLM诱导的肺纤维化作用在C57BL/6与ICR小鼠间存在着明显的种属差异。C57BL/6小鼠较ICR小鼠更适于复制博来霉素诱导的肺纤维化动物模型。

  • 标签: 小鼠 近交C57BL/6 近交ICR 博来霉素 肺纤维化
  • 简介:目的:观察Kozak序列(+4G)对稳定转染的人淀粉样前体蛋白(hAPP751)-EGFP融合真核表达载体在CHO细胞中表达的影响,为APP的水解代谢研究提供细胞模型。方法:分别将含Kozak序列(+4G)和不含Kozak序列的hAPP751全长基因片段亚克隆入pEGFP-N1表达载体,得到pEGFP-hAPP751(+4G)和pEGFP-hAPP751重组质粒,转染CHO细胞,通过G418筛选稳定转染细胞株,再用倒置荧光显微镜挑取绿色荧光强的细胞进行亚克隆,并观察融合蛋白的表达强度和细胞定位,最后用EGFP抗体通过Western印迹检测融合蛋白。结果:PCR、酶切和测序证明将含Kozak序列(+4G)和不含Kozak序列的hAPP751全长基因片段分别连入了真核表达载体pEGFP-N1中;荧光显微镜下观察pEGFP-hAPP751(+4G)稳定转染细胞的细胞膜和细胞质产生较强的绿色荧光,其中在细胞质中成不均匀颗粒状分布,Western印迹检测到相对分子质量约156000的融合表达蛋白,与预期相符;pEGFP-hAPP751转染细胞,其绿色荧光十分微弱且在整个细胞均匀分布,Western印迹检测到相对分子质量约26000的EGFP,但检测不到预期的hAPP751-EGFP融合表达蛋白。结论:Kozak序列(+4G)可以明显促进hAPP751的表达,获得稳定转染且高水平融合表达hAPP751-EGFP的细胞株。

  • 标签: Kozak序列(+4G) 人淀粉样前体蛋白751 增强型绿色荧光蛋白 阿尔茨海默病 真核表达