Preliminary Study On The Adaptability Of Pest Des Petits Ruminants Virus To Host In Genetic Evolution And Innate Immunity

Peste des petits ruminants virus is the pathogen of peste des petits ruminants,a fatal infectious disease of livestock.PPRV infection can make small ruminants suffer from pneumonia,erosive fatal stomatitis and enteritis.It is the First Class notifiable contagion in China.At present,the research on prevention and control methods belongs to the hotspot at the prevention of animal infectious diseases,but there are few studies on host adaptability of PPRV in genetic evolution and innate immune response.In this study,the adaptability of nucleotide,dinucleotide,synonymous codons and amino acids usage patterns of PPRV gene to host in genetic evolution and the IFN signaling pathway activated in 293 T cells by PPRV infection,which laid a foundation for further understanding of the relationship between PPRV and host in genetic evolution and innate immune system,and developments new method for the prevention and control of PPRV.The results are as follows:(1)The nucleotides,dinucleotides,synonymous codons and amino acids usage patterns of PPRV and RPV have been analyzed by multivariate statistical methods,such as relative synonymous codon usage,the relative dinucleotides abundance and the ‘effective number of codons'.The result showed there were significant differences in the usage of nucleotides,codons and amino acids between PPRV and RPV genes.The preference between PPRV and RPV was caused by the use of nucleotide and dinucleotide at the third codon position.The genetic evolution of dinucleotide,synonymous codon and amino acid usage preference of L genes of the two viruses had little difference in the host,but other genes differed greatly in the genetic evolution of the host.This preference may be related to the genetic evolution of the virus in the process of adapting to the host.(2)PPRV could proliferate in 293 T cells.At the transcriptional level,it could activate the antiviral pathway of interferon,stimulate the production of IFN-?,IFN-?2 and IFN-?3,and induce the expression of interferon-stimulating genes.However,IFN produced by PPRV-activated cells was not enough to play an antiviral role.Exogenous interferons IFN-?-2b,IFN-? and IFN-?3 could effectively inhibit the proliferation of PPRV,which was attenuted by JAK-inhibitor I,the inhibitor of JAKSTAT.In this research,in order to find out the adaptability of PPRV to host in genetic evolution,the nucleotides,dinucleotides,synonymous codons and amino acids of PPRV gene were analyzed,and the IFN signaling pathway of PPRV in 293 T cells were studied.These results provided a theoretical basis for the studing of the self-evolution of PPRV in antagonizing host immune defense to evade host immunity and develop new methods for PPRV revention and control.