The winter of 2009 witnessed the concurrent spread of 2009 pandemic H1N1 with 2009 seasonal H1N1. It is clinically important to develop knowledge of the key features of these two different viruses that make them uniqu...The winter of 2009 witnessed the concurrent spread of 2009 pandemic H1N1 with 2009 seasonal H1N1. It is clinically important to develop knowledge of the key features of these two different viruses that make them unique. A robust pattern recognition technique, Random Forests, was employed to uncover essential amino acid markers to differentiate the two viruses. Some of these markers were also part of the previously discovered genomic signature that separate avian or swine from human viruses. Much research to date in search of host markers in 2009 pandemic H1N1 has been primarily limited in the context of traditional markers of avian-human or swine-human host shifts. However, many of the molecular markers for adaptation to human hosts or to the emergence of a pandemic virus do not exist in 2009 pandemic H1N1, implying that other previously unrecognized molecular determinants are accountable for its capability to infect humans. The current study aimed to explore novel host markers in the proteins of 2009 pandemic H1N1 that were not present in those classical markers, thus providing fresh and unique insight into the adaptive genetic modifications that could lead to the generation of this new virus. Random Forests were used to find 18 such markers in HA, 15 in NA, 9 in PB2, 11 in PB1, 13 in PA, 10 in NS1, 1 in NS2, 11 in NP, 3 in M1, and 1 in M2. The amino acids at many of these novel sites in 2009 pandemic H1N1 were distinct from those in avian, human, and swine viruses that were identical at these positions, reflecting the uniqueness of these novel sites.展开更多
In the efforts to understand the molecular characteristics responsible for the ability of influenza viruses to cross species, various amino acid host markers in influenza viruses were uncovered. Our previous study ide...In the efforts to understand the molecular characteristics responsible for the ability of influenza viruses to cross species, various amino acid host markers in influenza viruses were uncovered. Our previous study identified a collection of novel amino acid host markers in ten proteins of 2009 pandemic H1N1. As an extension of our prior work, the objective of the current study was to employ Random Forests, a robust pattern recognition technique, to discover nucleotide host makers in the ten corresponding genes of 2009 pandemic H1N1, along with those in the genes of avian and swine viruses. Although different, there was an association between the amino acid markers in proteins and the nucleotide markers in the related genes due to codon translations. Moreover, nucleotide host markers have the capability to indicate important positions within a codon for host switches as well as the significance of synonymous mutations on host shifts, all of which amino acid markers could not provide. Our findings highlighted that two or even three nucleotide markers could coexist within a single codon, and the different importance values of these markers could further discri- minate the multiple markers within a codon. The nucleotide markers found in this study rendered a comprehensive genomic view of the complex and systemic nature of host adaptation. They verified and enriched the known amino acid markers and offered a larger set of finer host markers for further experimental confirmation.展开更多
[目的]探明柞蚕微粒子虫能否侵染非天然性宿主菜青虫。[方法]通过对纯化的柞蚕微粒子虫进行添食菜青虫,分析了不同浓度下柞蚕微孢子虫对菜青虫的侵染力差异,并采用SYBR Green I染液对菜青虫体液内的柞蚕微孢子虫进行染色,观察其形态。[...[目的]探明柞蚕微粒子虫能否侵染非天然性宿主菜青虫。[方法]通过对纯化的柞蚕微粒子虫进行添食菜青虫,分析了不同浓度下柞蚕微孢子虫对菜青虫的侵染力差异,并采用SYBR Green I染液对菜青虫体液内的柞蚕微孢子虫进行染色,观察其形态。[结果]柞蚕微粒子虫在转宿主情况下能够感染菜青虫,并且在特定浓度下能够在菜青虫体内大量增殖。[结论]为进一步开展柞蚕微粒子虫的非天然性寄生宿主范围以及转宿主后的分子机制研究奠定了基础。展开更多
文摘The winter of 2009 witnessed the concurrent spread of 2009 pandemic H1N1 with 2009 seasonal H1N1. It is clinically important to develop knowledge of the key features of these two different viruses that make them unique. A robust pattern recognition technique, Random Forests, was employed to uncover essential amino acid markers to differentiate the two viruses. Some of these markers were also part of the previously discovered genomic signature that separate avian or swine from human viruses. Much research to date in search of host markers in 2009 pandemic H1N1 has been primarily limited in the context of traditional markers of avian-human or swine-human host shifts. However, many of the molecular markers for adaptation to human hosts or to the emergence of a pandemic virus do not exist in 2009 pandemic H1N1, implying that other previously unrecognized molecular determinants are accountable for its capability to infect humans. The current study aimed to explore novel host markers in the proteins of 2009 pandemic H1N1 that were not present in those classical markers, thus providing fresh and unique insight into the adaptive genetic modifications that could lead to the generation of this new virus. Random Forests were used to find 18 such markers in HA, 15 in NA, 9 in PB2, 11 in PB1, 13 in PA, 10 in NS1, 1 in NS2, 11 in NP, 3 in M1, and 1 in M2. The amino acids at many of these novel sites in 2009 pandemic H1N1 were distinct from those in avian, human, and swine viruses that were identical at these positions, reflecting the uniqueness of these novel sites.
文摘In the efforts to understand the molecular characteristics responsible for the ability of influenza viruses to cross species, various amino acid host markers in influenza viruses were uncovered. Our previous study identified a collection of novel amino acid host markers in ten proteins of 2009 pandemic H1N1. As an extension of our prior work, the objective of the current study was to employ Random Forests, a robust pattern recognition technique, to discover nucleotide host makers in the ten corresponding genes of 2009 pandemic H1N1, along with those in the genes of avian and swine viruses. Although different, there was an association between the amino acid markers in proteins and the nucleotide markers in the related genes due to codon translations. Moreover, nucleotide host markers have the capability to indicate important positions within a codon for host switches as well as the significance of synonymous mutations on host shifts, all of which amino acid markers could not provide. Our findings highlighted that two or even three nucleotide markers could coexist within a single codon, and the different importance values of these markers could further discri- minate the multiple markers within a codon. The nucleotide markers found in this study rendered a comprehensive genomic view of the complex and systemic nature of host adaptation. They verified and enriched the known amino acid markers and offered a larger set of finer host markers for further experimental confirmation.
文摘[目的]探明柞蚕微粒子虫能否侵染非天然性宿主菜青虫。[方法]通过对纯化的柞蚕微粒子虫进行添食菜青虫,分析了不同浓度下柞蚕微孢子虫对菜青虫的侵染力差异,并采用SYBR Green I染液对菜青虫体液内的柞蚕微孢子虫进行染色,观察其形态。[结果]柞蚕微粒子虫在转宿主情况下能够感染菜青虫,并且在特定浓度下能够在菜青虫体内大量增殖。[结论]为进一步开展柞蚕微粒子虫的非天然性寄生宿主范围以及转宿主后的分子机制研究奠定了基础。
