Ebola virus （EBOV） is a key member of Filoviridae family and causes severe human infectious diseases with high morbidity and mortality. As a typical negative-sense single-stranded RNA （-ssRNA） viruses, EBOV posses...Ebola virus （EBOV） is a key member of Filoviridae family and causes severe human infectious diseases with high morbidity and mortality. As a typical negative-sense single-stranded RNA （-ssRNA） viruses, EBOV possess a nucleocapsid protein （NP） to facilitate genomic RNA encapsidation to form viral ribonucleoprotein complex （RNP） together with genome RNA and polymerase, which plays the most essential role in virus proliferation cycle. However, the mechanism of EBOV RNP formation remains unclear. In this work, we solved the high resolution structure of core domain of EBOV NP. The polypeptide of EBOV NP core domain （NPcore） pos- sesses an N-lobe and C-lobe to clamp a RNA binding groove, presenting similarities with the structures of the other reported viral NPs encoded by the members from Mononegavirales order. Most strikingly, a hydrophobic pocket at the surface of the C-lobe is occupied by an a- helix of EBOV NPcore itself, which is highly conserved among filoviridae family. Combined with other bio- chemical and biophysical evidences, our results provides great potential for understanding the mechanism underlying EBOV RNP formation via the mobility of EBOV NP element and enables the development of antiviral therapies targeting EBOV RNP formation.展开更多
A new substrate,aligned Ag nanowires decorated with silver nanoparticle composite structure(AgNWs@AgNPs),was fabricated to investigate metalenhanced fluorescence(MEF) and its mechanism.The new composite structure was ...A new substrate,aligned Ag nanowires decorated with silver nanoparticle composite structure(AgNWs@AgNPs),was fabricated to investigate metalenhanced fluorescence(MEF) and its mechanism.The new composite structure was fabricated via a three-phase interface assembly method followed by SnCl2 sensitization and AgNO3 reduction process.The size and distribution of the nanoparticles on silver nanowires increased with the sensitization and reduction cycles.The formation of AgNPs on the surfaces of AgNWs was confirmed by multiple characterization methods including scanning electron microscopy(SEM),transmission electron microscope(TEM),atomic force microscopy(AFM) and X-ray diffraction(XRD).The results show that the fluorescence intensity of the poly(3-hexylthiophene)(P3HT) on the composite structure was greatly enhanced compared with that on bare glass substrate,and the intensity increased with the increase in particle sizes and density.The mechanism was basedo n the increase in excitation rate and the radiation decay rate.The new type of substrate could serve as a good and efficient MEF substrate for high-performance fluorescence-based devices.展开更多
文摘Ebola virus （EBOV） is a key member of Filoviridae family and causes severe human infectious diseases with high morbidity and mortality. As a typical negative-sense single-stranded RNA （-ssRNA） viruses, EBOV possess a nucleocapsid protein （NP） to facilitate genomic RNA encapsidation to form viral ribonucleoprotein complex （RNP） together with genome RNA and polymerase, which plays the most essential role in virus proliferation cycle. However, the mechanism of EBOV RNP formation remains unclear. In this work, we solved the high resolution structure of core domain of EBOV NP. The polypeptide of EBOV NP core domain （NPcore） pos- sesses an N-lobe and C-lobe to clamp a RNA binding groove, presenting similarities with the structures of the other reported viral NPs encoded by the members from Mononegavirales order. Most strikingly, a hydrophobic pocket at the surface of the C-lobe is occupied by an a- helix of EBOV NPcore itself, which is highly conserved among filoviridae family. Combined with other bio- chemical and biophysical evidences, our results provides great potential for understanding the mechanism underlying EBOV RNP formation via the mobility of EBOV NP element and enables the development of antiviral therapies targeting EBOV RNP formation.
基金financially supported by the National Natural Science Foundation of China (No.51273048)Science and Technology Planning Project of Guangdong Province (No.2017B090915004)the Open Operation of Guangdong Provincial Key Laboratory of Advanced Coatings Research and Development (No.2017B030314105)
文摘A new substrate,aligned Ag nanowires decorated with silver nanoparticle composite structure(AgNWs@AgNPs),was fabricated to investigate metalenhanced fluorescence(MEF) and its mechanism.The new composite structure was fabricated via a three-phase interface assembly method followed by SnCl2 sensitization and AgNO3 reduction process.The size and distribution of the nanoparticles on silver nanowires increased with the sensitization and reduction cycles.The formation of AgNPs on the surfaces of AgNWs was confirmed by multiple characterization methods including scanning electron microscopy(SEM),transmission electron microscope(TEM),atomic force microscopy(AFM) and X-ray diffraction(XRD).The results show that the fluorescence intensity of the poly(3-hexylthiophene)(P3HT) on the composite structure was greatly enhanced compared with that on bare glass substrate,and the intensity increased with the increase in particle sizes and density.The mechanism was basedo n the increase in excitation rate and the radiation decay rate.The new type of substrate could serve as a good and efficient MEF substrate for high-performance fluorescence-based devices.
