口蹄疫病毒基因组密码子使用偏好性及其进化摘要:分析了FMDV基因编码起始区与终止区的密码子使用偏好性。实验主要选择了FMDV中最具代表性以及感染率最高的O型与A型进行密码子偏好性的分析以及进化方向的讨论。通过实验的数据可以得到初步的结论:在O血清型与A血清型的基因群落当中,并不存在固定同义密码子的使用模式。同时,即使这几个同义密码子属于同一种氨基酸,他们的使用频率也是不相同的,也从一方面说明了,基因组中存在着“优势密码子”和“稀有密码子”的现象。FMDV各血清型中的稀有密码子倾向出现于编码起始区,而终止区附近稀有密码子出现的倾向较弱。关于进化学方面的研究,本实验也采用了生物信息学软件SPSS,将FMDV基因组密码子参考序列的同源性进行了分析与对比,构建了A血清型的VP1基因的进化树,同时也可以通过对O型、A型绘制的进化谱图得到:目前已知的A型口蹄疫毒株与其它毒株序列差异较大。口蹄疫病毒的每种血清型都集中在一个家族中。通过本次研究对FMDV基因组密码子的分析,可以更加清晰的认识到FMDV的遗传多样性,在基因序列上相差也是比较大的。同时也从一方面证实了加强口蹄疫病理学的分析与调查,对FMDV的变异与进化进行实时的监测对于防控FMD起着非常重要的作用。关键词:口蹄疫病毒(FMDV);密码子偏好性;密码子相对使用概率;方差分析;进化FOOT-AND-MOUTHDISEASEVIRUSGENOMECODONUSAGEPREFERENCEANDITSEVOLUTIONAbstract:ThecodonusagepreferenceoftheFMDVgenecodinginitiationregionandterminationregionwasanalyzed.TheexperimentmainlyselectedthemostrepresentativeoftheFMDVandthehighestinfectionrateofO-typeandA-typeforcodonpreferenceanalysisandthediscussionofevolutionarydirection.Theuseofallsynonymouscodonsinthegenepoolsofthesetwoserotypeswasfoundtovaryrandomly.Moreover,thefrequencyofuseofseveraldifferentsynonymouscodesbelongingtothesameaminoacidisdifferent,amongwhichthereare"dominantcodons"(RSCU>1)and"rarecodons"(RSCU<1).RarecodonsineachserotypeofFMDVtendtooccurinthecodinginitiationregion,whilethetendencyofrarecodonsneartheterminationregionisweak.Regardingtheresearchonchemicalchemistry,thebioinformaticssoftwareSPSSwasusedtocomparethehomologyofthereferencesequence,andthephylogenetictreeoftheVP1geneofAserotypewasconstructed,andtheevolutionaryspectrumofO-typeandA-typecanalsobedrawn.ThefigureshowsthatthesequenceofthecurrentlyknowntypeAfoot-and-mouthdiseasestraindiffersgreatlyfromotherstrains.Eachserotypeoffoot-and-mouthdiseasevirusisconcentratedinonefamily.ThroughtheanalysisoftheFMDVgenomecodonsinthisstudy,thegeneticdiversityofFMDVcanbemoreclearlyrecognized,andthedifferenceingenesequenceisalsorelativelylarge.Atthesametime,italsoconfirmedtheanalysisandinvestigationofthepathologyoffoot-and-mouthdisease.Thereal-timemonitoringofthevariationandevolutionofFMDVplaysanimportantroleinthepreventionandcontrolofFMD.Keywords:footandmouthdiseasevirus(FMDV);codonpreference;relativesynonymouscodonusage;varianceanalysis;evolution目录第1章文献综述.............................................................................................................................11.1研究背景............................................................................................................................11.2口蹄疫病毒研究概况........................................................................................................11.2.1口蹄疫病毒的流行病学的概述.............................................................................11.2.2口蹄疫病毒基因组结构.........................................................................................21.2.3FMDVRNA二级结构....