目的探讨关于中东呼吸综合征-冠状病毒(middle east respiratory syndrome-coronavirus,MERS-CoV)调控非小细胞肺癌细胞A549补体系统抑制因子补体成分4结合蛋白Alpha(complement component 4 binding protein alpha,C4BPA)的机制。方法...目的探讨关于中东呼吸综合征-冠状病毒(middle east respiratory syndrome-coronavirus,MERS-CoV)调控非小细胞肺癌细胞A549补体系统抑制因子补体成分4结合蛋白Alpha(complement component 4 binding protein alpha,C4BPA)的机制。方法以是否MERS-CoV感染非小细胞肺癌细胞A549分为感染组和对照组,通过酶联免疫吸附试验(ELISA)、免疫印迹和实时荧光定量PCR(qPCR)分别检测2组细胞C4BPA的蛋白和mRNA表达情况。TargetScanHuman预测与C4BPA结合的miRNA,实时荧光定量PCR和荧光素酶报告试验确定靶向C4BPA的miRNA。在MERS-CoV感染的情况下,过表达或敲低靶向C4BPA的miRNA,ELISA或qPCR检测C4BPA的表达和分泌情况。同时分析人肺成纤维细胞和小鼠感染MERS-CoV后,C4BPA和miR-451b的表达情况。结果非小细胞肺癌细胞A549感染MERS-CoV后,其分泌的C4BPA增加(P<0.05)。通过TargetScanHuman在线分析和qPCR发现MERS-CoV抑制非小细胞肺癌细胞A549 miR-451b的表达(P<0.05),并且miR-451b靶向C4BPA的3‘UTR(P<0.05)。过表达miR-451b后,C4BPA的表达和分泌受到抑制(P<0.05)。敲低miR-451b后,C4BPA的表达和分泌受到促进(P<0.05)。同时,MERS-CoV感染人肺成纤维细胞和小鼠后,miR-451b的表达受到抑制(P<0.05),C4BPA的表达增强。并且,MERSCoV感染引起的C4BPA增多能够抑制补体经典系统的溶血活性。结论MERS-CoV通过下调miR-451b促进C4BPA的分泌。展开更多
[Objective] This study aimed to clone C4B gene in Siji goose and detect its expression level in different tissues. [Method] cDNA sequence of C4B gene was cloned with RACE-PCR method. Amino acid sequences in multiple s...[Objective] This study aimed to clone C4B gene in Siji goose and detect its expression level in different tissues. [Method] cDNA sequence of C4B gene was cloned with RACE-PCR method. Amino acid sequences in multiple species were aligned in GenBank, and a phylogenetic tree was constructed for homology analysis. [Result] C4B gene in Siji goose shared relatively high homology with chicken and quail; Siji goose C4B gene was expressed highly in liver and lung of adult geese and expressed lowly in epididymis, seminiferous duct, brain, kidney, testis, heart, oviduct and smal intestine. [Conclusion] In the present study, mRNA expression lev-el of C4B gene in different tissues and organs of Siji goose was determined by flu-orescence quantitative PCR, which provided basis for rapid diagnosis of specific an-imal diseases.展开更多
文摘目的探讨关于中东呼吸综合征-冠状病毒(middle east respiratory syndrome-coronavirus,MERS-CoV)调控非小细胞肺癌细胞A549补体系统抑制因子补体成分4结合蛋白Alpha(complement component 4 binding protein alpha,C4BPA)的机制。方法以是否MERS-CoV感染非小细胞肺癌细胞A549分为感染组和对照组,通过酶联免疫吸附试验(ELISA)、免疫印迹和实时荧光定量PCR(qPCR)分别检测2组细胞C4BPA的蛋白和mRNA表达情况。TargetScanHuman预测与C4BPA结合的miRNA,实时荧光定量PCR和荧光素酶报告试验确定靶向C4BPA的miRNA。在MERS-CoV感染的情况下,过表达或敲低靶向C4BPA的miRNA,ELISA或qPCR检测C4BPA的表达和分泌情况。同时分析人肺成纤维细胞和小鼠感染MERS-CoV后,C4BPA和miR-451b的表达情况。结果非小细胞肺癌细胞A549感染MERS-CoV后,其分泌的C4BPA增加(P<0.05)。通过TargetScanHuman在线分析和qPCR发现MERS-CoV抑制非小细胞肺癌细胞A549 miR-451b的表达(P<0.05),并且miR-451b靶向C4BPA的3‘UTR(P<0.05)。过表达miR-451b后,C4BPA的表达和分泌受到抑制(P<0.05)。敲低miR-451b后,C4BPA的表达和分泌受到促进(P<0.05)。同时,MERS-CoV感染人肺成纤维细胞和小鼠后,miR-451b的表达受到抑制(P<0.05),C4BPA的表达增强。并且,MERSCoV感染引起的C4BPA增多能够抑制补体经典系统的溶血活性。结论MERS-CoV通过下调miR-451b促进C4BPA的分泌。
文摘泛素连接酶E4B通过U-box基序可将经泛素活化酶(Ubiquitin-activating enzyme, E1)和泛素结合酶(Ubiquitin-conjugating enzyme, E2)传递的泛素(Ubiquitin, UB)标记至底物蛋白质。探究3个蛋白质:金属蛋白酶M20家族蛋白质2(Peptidase M20 domain-containing protein 2,PM20D2)、多腺苷酸结合蛋白质1(Polyadenylate-binding protein 1,PABPC1)、细胞色素C氧化酶Ⅰ翻译激活剂(Translational activator of cytochrome C oxidase Ⅰ,TACO1)是否可被E4B介导泛素化。从HEK293细胞中提取总RNA,反转录为cDNA,以其为模板调取底物基因并构建重组质粒,利用大肠杆菌表达系统表达并纯化泛素化过程所需的各个相关蛋白质,通过蛋白质体外泛素化实验,对3个蛋白质进行泛素化验证。结果表明3个蛋白质均可以在蛋白质水平被E4B泛素化,证明3个蛋白质都是E4B的底物,为进一步在细胞中研究其泛素化的机理奠定基础。
基金Supported by Agricultural Independent Innovation Fund of Jiangsu Province[CX(09)638]~~
文摘[Objective] This study aimed to clone C4B gene in Siji goose and detect its expression level in different tissues. [Method] cDNA sequence of C4B gene was cloned with RACE-PCR method. Amino acid sequences in multiple species were aligned in GenBank, and a phylogenetic tree was constructed for homology analysis. [Result] C4B gene in Siji goose shared relatively high homology with chicken and quail; Siji goose C4B gene was expressed highly in liver and lung of adult geese and expressed lowly in epididymis, seminiferous duct, brain, kidney, testis, heart, oviduct and smal intestine. [Conclusion] In the present study, mRNA expression lev-el of C4B gene in different tissues and organs of Siji goose was determined by flu-orescence quantitative PCR, which provided basis for rapid diagnosis of specific an-imal diseases.