儿童与成人慢性乙型肝炎患者的临床特征差异明显。乙型肝炎病毒(Hepatitis B virus,HBV)病毒准种特征与其致病特性紧密相连,HBV病毒Core基因区富含免疫表位,该区域的准种特征直接反映病毒变异与病毒应对宿主免疫压力间的动态过程。文章...儿童与成人慢性乙型肝炎患者的临床特征差异明显。乙型肝炎病毒(Hepatitis B virus,HBV)病毒准种特征与其致病特性紧密相连,HBV病毒Core基因区富含免疫表位,该区域的准种特征直接反映病毒变异与病毒应对宿主免疫压力间的动态过程。文章通过扩增170名儿童慢性乙型肝炎患者及121名成人慢性乙型肝炎患者病毒Core基因区,按照病毒基因型以及病毒e抗原(Hepatitis B virus e antigen,HBe Ag)状态进行分组,使用序列复杂度、多样性、非同义突变率(Non-synonymous substitution ratio,d N)、同义突变率(Synonymous substitution ratios,d S)等指标衡量不同组别之间的病毒准种特征;使用不同模型计算不同组别中受到正选择压力的位点,进一步结合HBV Core基因区免疫表位信息,进行正选择位点的定位分析。结果发现,儿童乙型肝炎病毒患者体内病毒Core基因区序列复杂性和多样性低于成人患者,且前者Core基因区正选择位点个数显著低于后者,这说明儿童慢性乙型肝炎患者体内病毒受到的选择压力低于成人患者。在儿童及成人慢性感染病人组中,HBe Ag阳性病人体内病毒受到的选择压力低于HBe Ag阴性病人。儿童及成人慢性感染患者体内病毒存在13个正选择位点,大多数正选择位点位于已知的抗原表位上。本研究从分子进化角度揭示了儿童与成人慢性乙型肝炎病例体内病毒Core基因区序列准种差异,为两类病人显著不同的临床表征提供了群体遗传学的解释。展开更多
目的构建丙肝病毒核心基因克隆载体pGEM-HCV/core,为进一步研究外部引导序列(external guide sequence,EGS)引导核糖核酸酶P在RNA水平阻断丙肝病毒核心基因的表达做好前期基础。方法将含HCV全长基因的pBRTM/HCV1-301l质粒于大肠杆菌JMl0...目的构建丙肝病毒核心基因克隆载体pGEM-HCV/core,为进一步研究外部引导序列(external guide sequence,EGS)引导核糖核酸酶P在RNA水平阻断丙肝病毒核心基因的表达做好前期基础。方法将含HCV全长基因的pBRTM/HCV1-301l质粒于大肠杆菌JMl09内扩增;提取pBRTM/HCV1-301l质粒;从pBRTM/HCV1-301l质粒中PCR扩增出HCV核心基因片段并将其插入pGEM-3Z克隆载体;以得到重组的pGEM-HCV/core克隆载体;最后EcoR I and Hind III双酶切鉴定HCV核心基因克隆载体。结果pGEM-HCV/core克隆载体经双酶切、凝胶电泳证明插入片段与HCV核心基因片段大小相符;经测序证明其插入序列与HCV core基因序列一致。结论成功构建了HCV核心基因的克隆载体pGEM-HCV/core。展开更多
The gene encoding the core and NS3 proteins of hepatitis C virus was amplified by PCR, respectirely. Two genes were fused and formed the recombinant plamid pHCV CN (Core+NS3) and pHCV NC (NS3+Core). The fused plasmid ...The gene encoding the core and NS3 proteins of hepatitis C virus was amplified by PCR, respectirely. Two genes were fused and formed the recombinant plamid pHCV CN (Core+NS3) and pHCV NC (NS3+Core). The fused plasmid were expressed in E.coli 06. The pHC CN plasmid expressed fussion protein was shown by a major band with a expected molecular weight about 68 kD on SDS PAGE. However, the pHCV NC plasmid expressed fussion protein was 66 kD in molecular weight. The results indicate that the pHCV NC fussion protein differs from the pHCV CN fussion protein in mulecular weight. It suggests that the fusion way is important for the structure of recombinant proteins.展开更多
文摘目的构建丙肝病毒核心基因克隆载体pGEM-HCV/core,为进一步研究外部引导序列(external guide sequence,EGS)引导核糖核酸酶P在RNA水平阻断丙肝病毒核心基因的表达做好前期基础。方法将含HCV全长基因的pBRTM/HCV1-301l质粒于大肠杆菌JMl09内扩增;提取pBRTM/HCV1-301l质粒;从pBRTM/HCV1-301l质粒中PCR扩增出HCV核心基因片段并将其插入pGEM-3Z克隆载体;以得到重组的pGEM-HCV/core克隆载体;最后EcoR I and Hind III双酶切鉴定HCV核心基因克隆载体。结果pGEM-HCV/core克隆载体经双酶切、凝胶电泳证明插入片段与HCV核心基因片段大小相符;经测序证明其插入序列与HCV core基因序列一致。结论成功构建了HCV核心基因的克隆载体pGEM-HCV/core。
文摘The gene encoding the core and NS3 proteins of hepatitis C virus was amplified by PCR, respectirely. Two genes were fused and formed the recombinant plamid pHCV CN (Core+NS3) and pHCV NC (NS3+Core). The fused plasmid were expressed in E.coli 06. The pHC CN plasmid expressed fussion protein was shown by a major band with a expected molecular weight about 68 kD on SDS PAGE. However, the pHCV NC plasmid expressed fussion protein was 66 kD in molecular weight. The results indicate that the pHCV NC fussion protein differs from the pHCV CN fussion protein in mulecular weight. It suggests that the fusion way is important for the structure of recombinant proteins.