本文对蒺藜苜蓿叶绿体基因组全序列密码子进行分析，筛选出50条CDS（coding DNA sequence）利用Codo-nW软件进行分析其密码子使用模式。结果显示，蒺藜苜蓿叶绿体基因组密码子第3位碱基GC含量为26．9％，即第3位密码子富含A和U，ENC值...本文对蒺藜苜蓿叶绿体基因组全序列密码子进行分析，筛选出50条CDS（coding DNA sequence）利用Codo-nW软件进行分析其密码子使用模式。结果显示，蒺藜苜蓿叶绿体基因组密码子第3位碱基GC含量为26．9％，即第3位密码子富含A和U，ENC值在37．11～51．91之间密码子偏好性较弱。相对同义密码子使用度分析显示RSCU值大于1的密码子有23个，其中以A和U为结尾20个。中性绘图分析显示GC12与GC3的相关系数为0．341，相关性不显著，回归系数为0．4843；单基因ENC比值多分布在-0．05～0．05，即大部分基因ENC值离ENC期望值较近；对应性分析，第一轴显示了12．50％的差异为主要影响因素，第一轴与ENC和GC。的相关系数分别为0．091和-0．092，均相关不显著。综合这几项分析发现蒺藜苜蓿叶绿体基因组密码子偏好性主要受到突变的影响，但是并不是唯一的影响因素，其他因素对密码子偏好性也可能有一定的影响。最终通过高表达优越密码子方法确定得出UUA、UUG、CCU等23个密码子为最优密码子，为之后对外源基因进行改造，提高其在叶绿体中的表达效率奠定了基础。展开更多
植物叶绿体psbA基因的启动子是叶绿体基因工程中常用的启动子,研究该基因的编码特点对完善叶绿体基因工程的研究设计、提高外源基因在受体物种中高效、稳定的表达具有重要作用。本研究综合运用了多种分析软件,对11种植物的叶绿体psbA基...植物叶绿体psbA基因的启动子是叶绿体基因工程中常用的启动子,研究该基因的编码特点对完善叶绿体基因工程的研究设计、提高外源基因在受体物种中高效、稳定的表达具有重要作用。本研究综合运用了多种分析软件,对11种植物的叶绿体psbA基因进行了分析。结果表明,11种植物psbA基因的ENC(Effective Number of Codons)值都小于40,显示出了明显的密码子偏好性,即在碱基组成上偏爱以C结尾的密码子。RSCU(Relative Synonymous Codon Usage)值表明共有20个密码子在编码使用上具有偏好性,其中有8个表现出较强的偏好性;另有12个密码子在psbA中出现率极低或没有出现。在聚类分析中,基于密码子偏好性参数RSCU的聚类不能正确反映物种间的进化关系,而基于基因序列的聚类更适合作为系统发育分析的参考。展开更多
AIM:To analyze the hepatitis B virus(HBV) characters in China,as well as the correlation between several HBV mutation and hepatitis symptoms.METHODS:A total of 1148 HBV genome sequences from patients throughout China ...AIM:To analyze the hepatitis B virus(HBV) characters in China,as well as the correlation between several HBV mutation and hepatitis symptoms.METHODS:A total of 1148 HBV genome sequences from patients throughout China were collected via the National Center For Biotechnology Information database(information including:genotype,territory and clinical status).HBV genotypes were classified by a direct reference from the Genbank sequence annotation,phylogenetic tree and online software analysis(http://www.ncbi.nlm.nih.gov/projects/genotyping/formpage.cgi).The phylogenetic tree was constructed based on the neighbor-joining method by MEGA5.0 software.HBV sequences were grouped based on phylogenetic tree and the distance between the groups was calculated by using the computer between group mean distance methods.Seven hundred and twelve HBV sequences with clear annotation of clinical symptoms were selected to analyses the correlation of mutation and clinical symptoms.Characteristics of sequences were analyzed by using DNAStar and BioEdit software packages.The codon usage bias and RNA secondary structures analysis were performed by RNAdraw software.Recombination analysis was performed by using Simplot software.RESULTS:In China,HBV genotype C was the predominant in Northeastern,genotype B was predominant in Central Southern areas,genotype B and C were both dominant in Southwestern areas,and the recombinant genotype C/D was predominant in Northwestern areas.C2 and B2 were identified as the two major sub-genotypes,FJ386674 might be a putative sub-genotype as B10.The basal core promoter double mutation and pre-C mutation showed various significant differences between hepatitis symptoms.In addition to ATG,many other HBV initiation codons also exist.HBV has codon usage bias;the termination codon of X,C and P open reading frames(ORF) were TAA,TAG,and TGA,respectively.The major stop codons of S-ORF were TAA(96.45%) and TGA(83.60%) in B2 and C2 subtype,respectively.CONCLUSION:This study recapitulated the epidemiology of HBV in China,展开更多
为了解降香黄檀叶绿体基因组密码子使用模式,该文利用Codon W 1.4.2和在线软件CUSP对降香黄檀叶绿体基因组中的52条基因编码序列密码子进行中性绘图、ENC-plot和PR2-plot分析。结果表明:降香黄檀叶绿体基因组密码子的3个位置上GC含量依...为了解降香黄檀叶绿体基因组密码子使用模式,该文利用Codon W 1.4.2和在线软件CUSP对降香黄檀叶绿体基因组中的52条基因编码序列密码子进行中性绘图、ENC-plot和PR2-plot分析。结果表明:降香黄檀叶绿体基因组密码子的3个位置上GC含量依次为GC1(46.01%)>GC2(38.98%)>GC3(27.80%)。有效密码子数(ENC)范围为37.66~54.43,及ENC值>45的有37个;RSCU>1的密码子有29个,其中16个以U结尾、12个以A结尾。这些说明其偏好以A和U结尾,且偏性较弱。中性绘图分析显示GC12与GC3的相关系数为0.250,相关性不显著,回归系数为0.394;ENC-plot分析显示ENC比值位于-0.05~0.05区间外的基因有38个;PR2-plot分析说明在碱基的使用频率方面,U>A、G>C,说明降香黄檀叶绿体基因组密码子偏好性主要受选择的影响;19个密码子被确定为最优密码子。该研究为降香黄檀叶绿体基因工程、遗传多样性分析等研究提供了科学参考依据。展开更多
以云南蓝果树叶绿体基因组为研究对象,采用Codon W 1.4.2等软件,通过分析云南蓝果树叶绿体基因组52个基因密码子的偏好性,探究影响密码子使用偏性形成的主要因素。结果表明:1)Codon W和CUSP软件分析显示密码子第3位碱基GC含量为28.40%,...以云南蓝果树叶绿体基因组为研究对象,采用Codon W 1.4.2等软件,通过分析云南蓝果树叶绿体基因组52个基因密码子的偏好性,探究影响密码子使用偏性形成的主要因素。结果表明:1)Codon W和CUSP软件分析显示密码子第3位碱基GC含量为28.40%,ENC值>45的基因有39个,说明密码子偏好以AT结尾,且存在较弱偏性。2)中性绘图分析显示,GC12与GC3的相关系数为0.1612,相关性不显著,说明密码子第1、第2位与第3位碱基组成存在显著差异。3)ENC绘图结合ENC比值频率表显示,大部分基因距离标准曲线较远,说明密码子偏好性主要受选择的影响。4)PR2-plot分析显示密码子第3位碱基使用频率方面,T>A,G>C,说明密码子偏好性受多重因素影响。5)确定UUG、UCA、GCU、AAU、GAU和GGA为最优密码子。综上所述,云南蓝果树叶绿体基因组密码子的使用主要受选择的影响,受其他如突变等因素的影响较弱。展开更多
文摘本文对蒺藜苜蓿叶绿体基因组全序列密码子进行分析，筛选出50条CDS（coding DNA sequence）利用Codo-nW软件进行分析其密码子使用模式。结果显示，蒺藜苜蓿叶绿体基因组密码子第3位碱基GC含量为26．9％，即第3位密码子富含A和U，ENC值在37．11～51．91之间密码子偏好性较弱。相对同义密码子使用度分析显示RSCU值大于1的密码子有23个，其中以A和U为结尾20个。中性绘图分析显示GC12与GC3的相关系数为0．341，相关性不显著，回归系数为0．4843；单基因ENC比值多分布在-0．05～0．05，即大部分基因ENC值离ENC期望值较近；对应性分析，第一轴显示了12．50％的差异为主要影响因素，第一轴与ENC和GC。的相关系数分别为0．091和-0．092，均相关不显著。综合这几项分析发现蒺藜苜蓿叶绿体基因组密码子偏好性主要受到突变的影响，但是并不是唯一的影响因素，其他因素对密码子偏好性也可能有一定的影响。最终通过高表达优越密码子方法确定得出UUA、UUG、CCU等23个密码子为最优密码子，为之后对外源基因进行改造，提高其在叶绿体中的表达效率奠定了基础。
文摘植物叶绿体psbA基因的启动子是叶绿体基因工程中常用的启动子,研究该基因的编码特点对完善叶绿体基因工程的研究设计、提高外源基因在受体物种中高效、稳定的表达具有重要作用。本研究综合运用了多种分析软件,对11种植物的叶绿体psbA基因进行了分析。结果表明,11种植物psbA基因的ENC(Effective Number of Codons)值都小于40,显示出了明显的密码子偏好性,即在碱基组成上偏爱以C结尾的密码子。RSCU(Relative Synonymous Codon Usage)值表明共有20个密码子在编码使用上具有偏好性,其中有8个表现出较强的偏好性;另有12个密码子在psbA中出现率极低或没有出现。在聚类分析中,基于密码子偏好性参数RSCU的聚类不能正确反映物种间的进化关系,而基于基因序列的聚类更适合作为系统发育分析的参考。
基金Supported by National Natural Science Foundation of China,No.81160352grants from the Education Department Foundation of Yunnan Province,No.2012J091+1 种基金Health Bureau of Yunnan Province,No.D-201203(partly)Science and Technology Department of Yunnan Province,No.2013HB084(partly)
文摘AIM:To analyze the hepatitis B virus(HBV) characters in China,as well as the correlation between several HBV mutation and hepatitis symptoms.METHODS:A total of 1148 HBV genome sequences from patients throughout China were collected via the National Center For Biotechnology Information database(information including:genotype,territory and clinical status).HBV genotypes were classified by a direct reference from the Genbank sequence annotation,phylogenetic tree and online software analysis(http://www.ncbi.nlm.nih.gov/projects/genotyping/formpage.cgi).The phylogenetic tree was constructed based on the neighbor-joining method by MEGA5.0 software.HBV sequences were grouped based on phylogenetic tree and the distance between the groups was calculated by using the computer between group mean distance methods.Seven hundred and twelve HBV sequences with clear annotation of clinical symptoms were selected to analyses the correlation of mutation and clinical symptoms.Characteristics of sequences were analyzed by using DNAStar and BioEdit software packages.The codon usage bias and RNA secondary structures analysis were performed by RNAdraw software.Recombination analysis was performed by using Simplot software.RESULTS:In China,HBV genotype C was the predominant in Northeastern,genotype B was predominant in Central Southern areas,genotype B and C were both dominant in Southwestern areas,and the recombinant genotype C/D was predominant in Northwestern areas.C2 and B2 were identified as the two major sub-genotypes,FJ386674 might be a putative sub-genotype as B10.The basal core promoter double mutation and pre-C mutation showed various significant differences between hepatitis symptoms.In addition to ATG,many other HBV initiation codons also exist.HBV has codon usage bias;the termination codon of X,C and P open reading frames(ORF) were TAA,TAG,and TGA,respectively.The major stop codons of S-ORF were TAA(96.45%) and TGA(83.60%) in B2 and C2 subtype,respectively.CONCLUSION:This study recapitulated the epidemiology of HBV in China,
文摘为了解降香黄檀叶绿体基因组密码子使用模式,该文利用Codon W 1.4.2和在线软件CUSP对降香黄檀叶绿体基因组中的52条基因编码序列密码子进行中性绘图、ENC-plot和PR2-plot分析。结果表明:降香黄檀叶绿体基因组密码子的3个位置上GC含量依次为GC1(46.01%)>GC2(38.98%)>GC3(27.80%)。有效密码子数(ENC)范围为37.66~54.43,及ENC值>45的有37个;RSCU>1的密码子有29个,其中16个以U结尾、12个以A结尾。这些说明其偏好以A和U结尾,且偏性较弱。中性绘图分析显示GC12与GC3的相关系数为0.250,相关性不显著,回归系数为0.394;ENC-plot分析显示ENC比值位于-0.05~0.05区间外的基因有38个;PR2-plot分析说明在碱基的使用频率方面,U>A、G>C,说明降香黄檀叶绿体基因组密码子偏好性主要受选择的影响;19个密码子被确定为最优密码子。该研究为降香黄檀叶绿体基因工程、遗传多样性分析等研究提供了科学参考依据。
文摘以云南蓝果树叶绿体基因组为研究对象,采用Codon W 1.4.2等软件,通过分析云南蓝果树叶绿体基因组52个基因密码子的偏好性,探究影响密码子使用偏性形成的主要因素。结果表明:1)Codon W和CUSP软件分析显示密码子第3位碱基GC含量为28.40%,ENC值>45的基因有39个,说明密码子偏好以AT结尾,且存在较弱偏性。2)中性绘图分析显示,GC12与GC3的相关系数为0.1612,相关性不显著,说明密码子第1、第2位与第3位碱基组成存在显著差异。3)ENC绘图结合ENC比值频率表显示,大部分基因距离标准曲线较远,说明密码子偏好性主要受选择的影响。4)PR2-plot分析显示密码子第3位碱基使用频率方面,T>A,G>C,说明密码子偏好性受多重因素影响。5)确定UUG、UCA、GCU、AAU、GAU和GGA为最优密码子。综上所述,云南蓝果树叶绿体基因组密码子的使用主要受选择的影响,受其他如突变等因素的影响较弱。
