Investigation of Deletion Variation and Methylation Patterns in the 5' LTR of Porcine Endogenous Retroviruses

  • Jung, K.C. (Division of Animal Science and Resources, Research Center for Transgenic Cloned Pigs Chungnam National University) ;
  • Simond, D.M. (Centre for Transplantation and Renal Research, Westmead Millennium Institute) ;
  • Moran, C. (Faculty of Veterinary Science, University of Sydney) ;
  • Hawthorne, W.J. (Centre for Transplantation and Renal Research, Westmead Millennium Institute) ;
  • Jeon, J.T. (Division of Applied Life Science, Gyeongsang National University) ;
  • Jin, D.I. (Division of Animal Science and Resources, Research Center for Transgenic Cloned Pigs Chungnam National University) ;
  • Lee, J.H. (Division of Animal Science and Resources, Research Center for Transgenic Cloned Pigs Chungnam National University)
  • Received : 2008.01.25
  • Accepted : 2008.07.09
  • Published : 2008.11.01


The xenotransplantation of pig organs and cells can be related with a risk of transmission of infectious diseases to human. Previous findings indicate that the regulatory region of PERV for retroviral transcription, replication and integration into the cellular DNA is located on the 5' Long Terminal Repeat (LTR). The objective of this study is the investigation of methylation and deletion status of the PERV 5' LTR region which can be used for regulating PERV expression. We compared the sequences of genomic DNA and bisulfite-treated genomic DNA from PK-15 cells expressing PERV to observe the methylation status of the 5' LTR. Our results showed that the CpG sites of U3 were methylated and methylation was inconsistent in the R and U5 regions. Also, variable numbers of 18 bp repeats and 21 bp repeats were detected on 5' LTR by sequencing analysis. The consistent U3 methylation might be indicative of host suppression of expression of the retroviruses.


Supported by : Rural Development Administration


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