Yu-Ai  Yang, Yong-Ke  Sun, Xiao-Min  Zhang, Min  Du, Yu-Xin  Li, Ling-Fu  Kong, Hong-Bin  Pan, Yu-Lin  Yan, 
    Construction of a Chimeric Virus Expressing Mutation Sequences of Classical Swine Fever Virus Yunnan Strain,
    Journal of Animal and Veterinary Advances,
    Volume 13,Issue 7,
    2014,
    Pages 470-476,
    ISSN 1680-5593,
    javaa.2014.470.476,
    (https://makhillpublications.co/view-article.php?doi=javaa.2014.470.476)
    Abstract: Infectious cDNA clones are a prerequisite for directed genetic 
  manipulation of RNA viruses. To explore the role of mutations in Classical Swine 
  Fever Virus (CSFV) Yunnan strain which caused the atypical clinical signs in 
  pigs, a new pSM derived from CSFV Shiman strain has been constructed and subsequently 
  replaced by the mutation sequences of CSFV YN strain isolated by the laboratory 
  at the positions 1510-1532, 2471-2658, 3152-3176 and 11785-11816 using the targeted 
  recombination strategy to enable rescue of chimeric CSFV. The results showed 
  that chimeric CSFV (vSM-YN) was successfully rescued from PK-15 cells by transfection 
  of the chimeric CSFV RNA transcripts and identified by whole genome sequence 
  analysis, immunofluorescence antibody assay and ELISA detection. Sequencing 
  of the pAC-SM-YN revealed a high genetic stability and the complete genome sequences 
  of rescued viruses vSM-YN after extensive passages in PK-15 cells showed that 
  modifications in pSM were stably maintained. The results indicate that targeted 
  recombination-mediated mutagenesis provides a powerful tool for expediting the 
  construction of novel RNA genomes and should facilitate further study of the 
  pathogenic mechanism of CSFV leading to atypical CSF.
    Keywords: RNA;CSFV;chimeric virus;construction;genetic stability;infectious molecular clone