Infectious bursal disease virus（IBDV）is responsible for the highly contagious infectious bursal disease of chickens.Further understanding the gene-function is necessary to design the tailored vaccine.The amino acid ...Infectious bursal disease virus（IBDV）is responsible for the highly contagious infectious bursal disease of chickens.Further understanding the gene-function is necessary to design the tailored vaccine.The amino acid residue 279,located on strand P_F of VP2,is one of the three residues that have been reported to be involved in cell-tropism but with some inconsistency.In this study,to further clarify the amino acids involved in the cell tropism of IBDV,a series of mutations about residue 279were introduced into the VP2 of vv IBDV Gx strain.With the reverse genetic system,we found single mutation of D279N,double mutations of D279N/A284T or Q253H/D279N were not enough to adapt IBDV to chicken embryo fibroblast（CEF）cell.To evaluate whether residue 279 could influence the replication and virulence of IBDV,the virus r Gx HT-279 with three mutations（Q253H/D279N/A284T）was rescued and evaluated.Results showed that the mutation of residue 279 in VP2had no efficient effects on both the replication efficiency in vitro and the virulence to SPF chickens of IBDV.In summary,the results demonstrated that residue 279 of VP2 did not contribute efficiently to cell tropism,replication efficiency,and virulence of IBDV at least in some strains.These findings provided further information for understanding the gene function of IBDV.展开更多
本文利用UMRAO(the University of Michigan Radio Observatory)射电天文台的观测数据,给出了3C 279射电4.8 GHz、8 GHz和14.5 GHz的历史光变曲线.利用离散相关函数方法(DCF)对其光变曲线进行相关性分析,发现在3C279在射电4.8 GHz、8 GH...本文利用UMRAO(the University of Michigan Radio Observatory)射电天文台的观测数据,给出了3C 279射电4.8 GHz、8 GHz和14.5 GHz的历史光变曲线.利用离散相关函数方法(DCF)对其光变曲线进行相关性分析,发现在3C279在射电4.8 GHz、8 GHz和14.5 GHz波段的辐射有显著的相关性,并存在时间延迟现象.展开更多
基金supported by a grant from National Natural Science Foundation of China(31430087)the Scientific and Technological Research Project of Harbin,China(2014AB3AN058)+2 种基金the Special Fund for Scientific and Technological Innovative Talents of Harbin,China(2014RFQYJ129)China-France Cai-Yuanpei Program(2011008007)the Modern Agro-industry Technology Research System of China(nycytx-42-G3-01)
文摘Infectious bursal disease virus（IBDV）is responsible for the highly contagious infectious bursal disease of chickens.Further understanding the gene-function is necessary to design the tailored vaccine.The amino acid residue 279,located on strand P_F of VP2,is one of the three residues that have been reported to be involved in cell-tropism but with some inconsistency.In this study,to further clarify the amino acids involved in the cell tropism of IBDV,a series of mutations about residue 279were introduced into the VP2 of vv IBDV Gx strain.With the reverse genetic system,we found single mutation of D279N,double mutations of D279N/A284T or Q253H/D279N were not enough to adapt IBDV to chicken embryo fibroblast（CEF）cell.To evaluate whether residue 279 could influence the replication and virulence of IBDV,the virus r Gx HT-279 with three mutations（Q253H/D279N/A284T）was rescued and evaluated.Results showed that the mutation of residue 279 in VP2had no efficient effects on both the replication efficiency in vitro and the virulence to SPF chickens of IBDV.In summary,the results demonstrated that residue 279 of VP2 did not contribute efficiently to cell tropism,replication efficiency,and virulence of IBDV at least in some strains.These findings provided further information for understanding the gene function of IBDV.
文摘本文利用UMRAO(the University of Michigan Radio Observatory)射电天文台的观测数据,给出了3C 279射电4.8 GHz、8 GHz和14.5 GHz的历史光变曲线.利用离散相关函数方法(DCF)对其光变曲线进行相关性分析,发现在3C279在射电4.8 GHz、8 GHz和14.5 GHz波段的辐射有显著的相关性,并存在时间延迟现象.
