Severe fever with thrombocytopenia syndrome virus(SFTSV),a member of the Phlebovirus genus from the Bunyaviridae family endemic to China,is the causative agent of life-threatening severe fever with thrombocyto-penia s...Severe fever with thrombocytopenia syndrome virus(SFTSV),a member of the Phlebovirus genus from the Bunyaviridae family endemic to China,is the causative agent of life-threatening severe fever with thrombocyto-penia syndrome(SFTS),which features high fever and hemorrhage.Similar to other negative-sense RNA viruses,SFTSV encodes a nucleocapsid protein(NP)that is essen-tial for viral replication.NP facilitates viral RNA encapsida-tion and is responsible for the formation of ribonucleopro-tein complex.However,recent studies have indicated that NP from Phlebovirus members behaves in inhomogene-ous oligomerization states.In the present study,we report the crystal structure of SFTSV NP at 2.8Åresolution and demonstrate the mechanism by which it processes a ring-shaped hexameric form to accomplish RNA encapsida-tion.Key residues essential for oligomerization are identi-fi ed through mutational analysis and identifi ed to have a signifi cant impact on RNA binding,which suggests that correct formation of highly ordered oligomers is a criti-cal step in RNA encapsidation.The fi ndings of this work provide new insights into the discovery of new antiviral reagents for Phlebovirus infection.展开更多
基金the National Basic Research Program(973 Program)(No.2013CB911103)the National Natural Science Foundation of China(Grant Nos.31170678,31170158,31000332,and 81102374)the Key Projects in the Tianjin Science and Technology Pillar Program(Grant Nos.11ZCKF-SY06900 and 11ZCKFSY06300).
文摘Severe fever with thrombocytopenia syndrome virus(SFTSV),a member of the Phlebovirus genus from the Bunyaviridae family endemic to China,is the causative agent of life-threatening severe fever with thrombocyto-penia syndrome(SFTS),which features high fever and hemorrhage.Similar to other negative-sense RNA viruses,SFTSV encodes a nucleocapsid protein(NP)that is essen-tial for viral replication.NP facilitates viral RNA encapsida-tion and is responsible for the formation of ribonucleopro-tein complex.However,recent studies have indicated that NP from Phlebovirus members behaves in inhomogene-ous oligomerization states.In the present study,we report the crystal structure of SFTSV NP at 2.8Åresolution and demonstrate the mechanism by which it processes a ring-shaped hexameric form to accomplish RNA encapsida-tion.Key residues essential for oligomerization are identi-fi ed through mutational analysis and identifi ed to have a signifi cant impact on RNA binding,which suggests that correct formation of highly ordered oligomers is a criti-cal step in RNA encapsidation.The fi ndings of this work provide new insights into the discovery of new antiviral reagents for Phlebovirus infection.
