【目的】监测当前湖南省猪圆环病毒2型(Porcine circovirus type 2,PCV2)流行毒株及其衣壳蛋白(capsid protein,Cap)变异情况,并预测Cap蛋白细胞毒性T淋巴细胞(cytotoxic T lymphocyte,CTL)表位,为新型PCV2疫苗研制和病毒净化提供参考...【目的】监测当前湖南省猪圆环病毒2型(Porcine circovirus type 2,PCV2)流行毒株及其衣壳蛋白(capsid protein,Cap)变异情况,并预测Cap蛋白细胞毒性T淋巴细胞(cytotoxic T lymphocyte,CTL)表位,为新型PCV2疫苗研制和病毒净化提供参考依据。【方法】本研究对2019-2021年于湖南省6个地区收集的17份PCV2阳性组织样品进行PCV2全基因组序列扩增及测序分析,绘制系统进化树,利用生物信息学方法分析Cap蛋白氨基酸变异情况,并预测CTL表位。【结果】系统进化树显示,获得的17株PCV2全基因组序列中,1株PCV2a、7株PCV2b和9株PCV2d。Cap蛋白氨基酸序列比对分析发现,共有16个氨基酸残基突变位点位于病毒Cap蛋白表面,且有11个突变位点参与构象型表位的形成。此外,共预测出9个PCV2 Cap蛋白潜在的CTL表位,其中4个表位(16-24、28-36、136-144和179-187位氨基酸)在GenBank的1610株PCV2不同基因型毒株中高度保守。通过TCR-pMHC复合物3D结构对4个保守性表位进一步分析,结果显示,这4个肽段均能与MHCⅠ分子和TCR形成稳定的TCR-pMHC复合物。【结论】本研究结果表明,PCV2b和PCV2d为当前湖南省主要流行的基因型,且表现出高度变异;预测的CTL表位可作为候选抗原表位。展开更多
Protein-losing enteropathy(PLE) is characterized by loss of serum proteins into the gastrointestinal tract. It may lead to hypoproteinemia and clinically present as protein deficiency edema, ascites, pleural or perica...Protein-losing enteropathy(PLE) is characterized by loss of serum proteins into the gastrointestinal tract. It may lead to hypoproteinemia and clinically present as protein deficiency edema, ascites, pleural or pericardial effusion and/or malnutrition. In most cases the site of protein loss is the small intestine. Here we present an unusual case of severe PLE in a 55-year old female with a one-year history of recurrent diarrhea, crampy abdominal pain, and peripheral edema. Endoscopy and MRI showed a diffuse inflammatory thickening of the sigmoid colon and the rectum. Surgical resection of the involved colon was performed and the symptoms were significantly resolved. The final histologic evaluation confirmed a diagnosis of a pseudomembranous colitis with cap polyposis-like features. Such a cause of PLE has never been described before.展开更多
A Flp/FRT EMS mutagenesis screen was conducted in the eye of Drosophila melanogaster on chromosome 2R to identify negative regulators of cell growth and cell division. In addition to the EMS mutation in the mosaic eye...A Flp/FRT EMS mutagenesis screen was conducted in the eye of Drosophila melanogaster on chromosome 2R to identify negative regulators of cell growth and cell division. In addition to the EMS mutation in the mosaic eye, an ark loss of function allele (ark<sup>82</sup>) was utilized to block apoptosis in the homozygous mutant cells, setting up a screen for conditional regulators of cell growth and cell division. In the present study, we focus on the characterization and mapping of one mutant that resulted from this screen, Cruella (cru). A cross between flies with the flippase enzyme directed to the developing eye and flies with the mutations cru, ark<sup>82</sup>, revealed an unusual phenotype that resulted in the homozygous mutant tissue appearing black, in contrast to the expected red. To map the location of this mutation, complementation tests against the Bloomington deficiency kit were conducted. Cru failed to complement previously characterized alleles of capping protein α (cpa). Thus, cpa<sup>cru</sup> is a novel allele of cpa and displays phenotypes similar to previously characterized alleles such as cpa 107E, cpa 69E, and cpa<sup>scrd</sup> . The human homolog, Cap Z, is conserved in humans and serves a similar role in act in filament regulation.展开更多
Circoviridae represent a growing family of small animal viruses. Some of these viruses have veterinary and medical importance, although, a vast amount of these newly discovered viruses have unknown effects on their ho...Circoviridae represent a growing family of small animal viruses. Some of these viruses have veterinary and medical importance, although, a vast amount of these newly discovered viruses have unknown effects on their hosts. The capsid-associated protein (Cap) of circoviruses is of interest because of its role in viral structure, immune evasion, host cell entry, and nuclear shuttling of viral components. The structure of the porcine circovirus 2 (PCV2) Cap has been solved and offered insight to these functions. Based on the crystallographic PCV2 Cap structure, models from circoviruses isolated from avian, fish, and mammalian hosts have been constructed and analyzed to better understand the roles of these proteins in the virus family. A high degree of conservation is observed in the models, however, the surface antigens differ among viruses. This is likely a reflection of the small genome harbored by circoviruses, and therefore the requirement of their few proteins to carry out specific vital functions, while maintaining enough variation to successfully infect their hosts. Here we describe the putative structures of a range of Cap proteins from circoviruses based on the crystallographic determination of porcine Cap, identifying key regions for function and inhibition of crystal formation.展开更多
目的筛选双孢蘑菇采后开伞相关差异蛋白,探究双孢蘑菇采后开伞的分子机制。方法选用贮藏前(0d)和刚破膜开伞(6d)的双孢蘑菇子实体为实验材料,通过同位素标记的相对和绝对定量(isobaric tags for relative and absolute quantitation,iTR...目的筛选双孢蘑菇采后开伞相关差异蛋白,探究双孢蘑菇采后开伞的分子机制。方法选用贮藏前(0d)和刚破膜开伞(6d)的双孢蘑菇子实体为实验材料,通过同位素标记的相对和绝对定量(isobaric tags for relative and absolute quantitation,iTRAQ)蛋白质组学技术筛选与双孢蘑菇采后破膜开伞相关的差异表达蛋白,并通过GO分析、KEGG通路富集分析等生物信息学手段对差异表达蛋白进行分析鉴定。结果贮藏0 d和6 d的两组双孢蘑菇样品中共鉴定到差异表达蛋白808个,包括285个上调蛋白和523个下调蛋白。与基因组数据库比对发现,筛选到的差异蛋白仅有38个被注释,且注释蛋白主要与精氨酸代谢、核酸代谢、糖代谢和氧化反应等生物学过程密切相关。GO功能和KEGG通路富集显示开伞相关差异蛋白主要富集在质膜细胞结构中,参与氰基氨基酸代谢、苯丙烷生物合成、糖代谢、精氨酸与脯氨酸代谢等途径。结论差异蛋白涉及的信号途径和代谢过程,特别是精氨酸代谢过程,在双孢蘑菇采后开伞过程发挥重要的调控作用。展开更多
文摘【目的】监测当前湖南省猪圆环病毒2型(Porcine circovirus type 2,PCV2)流行毒株及其衣壳蛋白(capsid protein,Cap)变异情况,并预测Cap蛋白细胞毒性T淋巴细胞(cytotoxic T lymphocyte,CTL)表位,为新型PCV2疫苗研制和病毒净化提供参考依据。【方法】本研究对2019-2021年于湖南省6个地区收集的17份PCV2阳性组织样品进行PCV2全基因组序列扩增及测序分析,绘制系统进化树,利用生物信息学方法分析Cap蛋白氨基酸变异情况,并预测CTL表位。【结果】系统进化树显示,获得的17株PCV2全基因组序列中,1株PCV2a、7株PCV2b和9株PCV2d。Cap蛋白氨基酸序列比对分析发现,共有16个氨基酸残基突变位点位于病毒Cap蛋白表面,且有11个突变位点参与构象型表位的形成。此外,共预测出9个PCV2 Cap蛋白潜在的CTL表位,其中4个表位(16-24、28-36、136-144和179-187位氨基酸)在GenBank的1610株PCV2不同基因型毒株中高度保守。通过TCR-pMHC复合物3D结构对4个保守性表位进一步分析,结果显示,这4个肽段均能与MHCⅠ分子和TCR形成稳定的TCR-pMHC复合物。【结论】本研究结果表明,PCV2b和PCV2d为当前湖南省主要流行的基因型,且表现出高度变异;预测的CTL表位可作为候选抗原表位。
文摘Protein-losing enteropathy(PLE) is characterized by loss of serum proteins into the gastrointestinal tract. It may lead to hypoproteinemia and clinically present as protein deficiency edema, ascites, pleural or pericardial effusion and/or malnutrition. In most cases the site of protein loss is the small intestine. Here we present an unusual case of severe PLE in a 55-year old female with a one-year history of recurrent diarrhea, crampy abdominal pain, and peripheral edema. Endoscopy and MRI showed a diffuse inflammatory thickening of the sigmoid colon and the rectum. Surgical resection of the involved colon was performed and the symptoms were significantly resolved. The final histologic evaluation confirmed a diagnosis of a pseudomembranous colitis with cap polyposis-like features. Such a cause of PLE has never been described before.
文摘A Flp/FRT EMS mutagenesis screen was conducted in the eye of Drosophila melanogaster on chromosome 2R to identify negative regulators of cell growth and cell division. In addition to the EMS mutation in the mosaic eye, an ark loss of function allele (ark<sup>82</sup>) was utilized to block apoptosis in the homozygous mutant cells, setting up a screen for conditional regulators of cell growth and cell division. In the present study, we focus on the characterization and mapping of one mutant that resulted from this screen, Cruella (cru). A cross between flies with the flippase enzyme directed to the developing eye and flies with the mutations cru, ark<sup>82</sup>, revealed an unusual phenotype that resulted in the homozygous mutant tissue appearing black, in contrast to the expected red. To map the location of this mutation, complementation tests against the Bloomington deficiency kit were conducted. Cru failed to complement previously characterized alleles of capping protein α (cpa). Thus, cpa<sup>cru</sup> is a novel allele of cpa and displays phenotypes similar to previously characterized alleles such as cpa 107E, cpa 69E, and cpa<sup>scrd</sup> . The human homolog, Cap Z, is conserved in humans and serves a similar role in act in filament regulation.
文摘Circoviridae represent a growing family of small animal viruses. Some of these viruses have veterinary and medical importance, although, a vast amount of these newly discovered viruses have unknown effects on their hosts. The capsid-associated protein (Cap) of circoviruses is of interest because of its role in viral structure, immune evasion, host cell entry, and nuclear shuttling of viral components. The structure of the porcine circovirus 2 (PCV2) Cap has been solved and offered insight to these functions. Based on the crystallographic PCV2 Cap structure, models from circoviruses isolated from avian, fish, and mammalian hosts have been constructed and analyzed to better understand the roles of these proteins in the virus family. A high degree of conservation is observed in the models, however, the surface antigens differ among viruses. This is likely a reflection of the small genome harbored by circoviruses, and therefore the requirement of their few proteins to carry out specific vital functions, while maintaining enough variation to successfully infect their hosts. Here we describe the putative structures of a range of Cap proteins from circoviruses based on the crystallographic determination of porcine Cap, identifying key regions for function and inhibition of crystal formation.
文摘目的筛选双孢蘑菇采后开伞相关差异蛋白,探究双孢蘑菇采后开伞的分子机制。方法选用贮藏前(0d)和刚破膜开伞(6d)的双孢蘑菇子实体为实验材料,通过同位素标记的相对和绝对定量(isobaric tags for relative and absolute quantitation,iTRAQ)蛋白质组学技术筛选与双孢蘑菇采后破膜开伞相关的差异表达蛋白,并通过GO分析、KEGG通路富集分析等生物信息学手段对差异表达蛋白进行分析鉴定。结果贮藏0 d和6 d的两组双孢蘑菇样品中共鉴定到差异表达蛋白808个,包括285个上调蛋白和523个下调蛋白。与基因组数据库比对发现,筛选到的差异蛋白仅有38个被注释,且注释蛋白主要与精氨酸代谢、核酸代谢、糖代谢和氧化反应等生物学过程密切相关。GO功能和KEGG通路富集显示开伞相关差异蛋白主要富集在质膜细胞结构中,参与氰基氨基酸代谢、苯丙烷生物合成、糖代谢、精氨酸与脯氨酸代谢等途径。结论差异蛋白涉及的信号途径和代谢过程,特别是精氨酸代谢过程,在双孢蘑菇采后开伞过程发挥重要的调控作用。