Homodimerization of Marek's disease virus-encoded Meq protein is not sufficient for transformation of lymphocytes in chickens.
Marek's disease virus (MDV), the etiologic agent of Marek's disease, is a potent oncogenic herpesvirus. MDV is highly contagious and elicits a rapid onset of malignant T-cell lymphomas in chickens within several weeks after infection. MDV genome codes an oncoprotein, Meq, which shares resemblance with the Jun/Fos family of bZIP transcription factors. Similar to Jun, the leucine zipper region of Meq allows the formation of homo- and heterodimers. Meq homo- and heterodimers have different DNA binding affinities and transcriptional activity; therefore, they may differentially regulate transcription of viral and cellular genes. In this study we investigated the role of Meq homodimers in the pathogenicity of MDV by generating a chimeric meq gene, which contains the leucine zipper region of the yeast transcription factor GCN4 (meqGCN). A recombinant virus (rMd5-MeqGCN) containing the chimeric meqGCN gene in place of parental meq was generated with overlapping cosmid clones of Md5, a very virulent MDV strain. The rMd5-MeqGCN virus replicated in vitro and in vivo but was unable to transform T cells in infected chickens. These data provide the first in vivo evidence that Meq homodimers are not sufficient for MDV-induced transformation.
Suchodolski
Paulette F
PF
Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas 77843, USA.
Izumiya
Yoshihiro
Y
Lupiani
Blanca
B
Ajithdoss
Dharani K
DK
Gilad
Oren
O
Lee
Lucy F
LF
Kung
Hsing-Jien
HJ
Reddy
Sanjay M
SM
D000818:Animals; D002472:Cell Transformation, Viral; D002645:Chickens; D004372:Ducks; D005347:Fibroblasts / Q000821:virology; D008214:Lymphocytes / Q000821:virology*; D025922:Mardivirus / Q000472:pathogenicity*; D008380:Marek Disease / Q000821:virology*; D015513:Oncogene Proteins / Q000378:metabolism; D011201:Poultry Diseases / Q000821:virology*; D055503:Protein Multimerization; D014764:Viral Proteins / Q000378:metabolism*; D037521:Virulence Factors / Q000378:metabolism*
D015513:Oncogene Proteins; D014764:Viral Proteins; D037521:Virulence Factors