GENETIC AND BIOLOGICAL DETERMINANTS OF AVIAN TUMOR VIRUS PATHOGENICITY, TRANSMISSION, AND EVOLUTION
Location: Avian Disease and Oncology Laboratory
Title: Marek’s disease virus encoded ribonucleotide reductase large subunit is essential for in vivo replication and plays a critical role in viral pathogenesis.
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: June 24, 2012
Publication Date: June 24, 2012
Citation: Sun, A., Lee, L.F., Heidari, M., Zhang, H., Lupiani, B., Reddy, S.M. 2012. Marek’s disease virus encoded ribonucleotide reductase large subunit is essential for in vivo replication and plays a critical role in viral pathogenesis [abstract]. 9th International Symposium on Marek's Disease and Avian Herpesviruses, June 24-28, 2012, Freie Universitat Berlin. p. 60.
Marek’s disease virus encodes a ribonucleotide reductase (RR) that consists of two subunits namely RR1 and RR2, both of which associate to form an active holoenzyme and both subunits are necessary for enzyme activity. It is an essential enzyme for the conversion of ribonucleotides to deoxyribonucleotides in prokaryotic and eukaryotic cells. MDV RR is abundantly expressed in the cytoplasm of MDV infected duck embryo fibroblasts as well as in chickens infected with MDV as determined using a monoclonal antibody specific for RR. We have generated a recombinant MDV in which RR1 was deleted (rMd5BAC'rr) and a revertant rMd5BAC'rrR. The RR deletion mutant grew significantly slower than the parent rMd5BAC whereas the revertant virus grew similar to the parental virus in vitro. Pathogenesis studies showed that the revertant virus functions similarly to that of parental virus whereas RR deletion virus did not replicate in vivo thus did not induced tumor in chickens. Our results show that RR is essential for MDV replication in vivo, and plays a critical role in viral pathogenesis.