fis对伤寒沙门菌基因表达的系统调节作用

《fis对伤寒沙门菌基因表达的系统调节作用》由会员上传分享，免费在线阅读，更多相关内容在学术论文-天天文库。

1、Fis对伤寒沙门菌基因表达的系统调节作用作者：李安平，谢新民　茅凌翔，杜鸿，王敏，罗哲，黄新祥【摘要】目的：探讨伤寒沙门菌调节因子fis对基因表达的系统调节作用。方法：用自杀质粒介导的同源重组方法制备伤寒沙门菌fis基因缺陷变异株，用脉冲场凝胶电泳分析fis缺陷变异株的基因组结构。利用伤寒沙门菌全基因组DNA芯片分析技术，比较伤寒沙门菌野生株和fis基因缺陷变异株的基因表达谱差异。用重组载体pBADfis回补fis缺陷变异株，选择部分差异表达基因进行qRTPCR验证，用半固体平板培养观察野生株、fis缺陷变异株和回补株

2、的动力。结果：fis基因缺陷变异株含有二相鞭毛素编码基因的线性质粒缺失，且动力消失;基因表达谱比较分析结果表明，伤寒沙门菌fis基因缺陷变异株在对数生长期94个基因出现表达差异;qRTPCR分析所选基因表达的结果与芯片分析结果相符;fis缺陷变异株在回补fis基因后，动力及差异表达基因都获得明显恢复。结论：Fis在伤寒沙门菌中对动力、侵袭及多种代谢相关基因的表达发挥重要调节作用。【关键词】伤寒沙门菌;Fis;基因芯片;脉冲场凝胶电泳;基因表达调节　　[Abstract]Objective:Toexplorethesys

3、temicregulationoffactorforinversionstimulation(fis)ongene16expressioninSalmonellaentericaserovarTyphi.Methods：ThefisdeletedmutantofS.entericaserovarTyphiwaspreparedbyhomologousrecombinationmediatedbysuicideplasmid;Pulsefieldgelelectrophoresiswasperformedtoinvest

4、igatethegenomestructureofthefismutantstrain.ThegeneexpressionprofilesofwildtypeandfisdeletedmutantofS.entericaserovarTyphiincubatedatlogphasewereinvestigatedbyS.entericaserovarTyphigenomicDNAmicroarrayanalysis.Arecombinantplasmid,pBADfis,containingthefisgenewith

5、itsownpromoterwasconstructed.qRTPCRwasperformedtovalidatetheresultsofmicroarrayinsomeselectedgenes.TheeffectofFisonthemotilityphenotypewasestablishedbytestsonsemisolidagarplates.Results：Inthefisdeletedmutant,thelinearplasmidcontainingphase2flagellingenefljBAwas

6、absentandthemotilitywasalsolost;geneexpressionprofilesanalysisrevealedthatexpressionof94geneswereinducedordecreasedinthefismutantatlogphase;expressionoftheselectedgenesinvestigatedbyqRTPCRwassimilartotheresultofmicroarrayassay;aftercomplementingfisgeneinthefisde

7、letedmutant,themotilityandexpressionofselectedgeneswereobviouslyrestored.Conclusion：Fismayplaythecentralroleincoordinatingtheexpressionofgenesinvolvedinmotile,andin16invasionorsubstancemetabolisminS.entericaserovarTyphi.　　[Keywords]S.entericaserovarTyphi;factorfo

8、rinversionstimulation;microarray;PFGE;geneexpressionregulation　　沙门菌和大肠埃希菌含有丰富的小型结合蛋白，这些结合蛋白统称为核相关蛋白(nucleoidassociatedproteins，NAPs)。核相关蛋白可与DNA结合，从而引起细菌核酸的结构变