Expression and DNA binding of budgerigar fledgling disease virus large T antigen

J Gen Virol. 1994 Jun;75 ( Pt 6):1267-80. doi: 10.1099/0022-1317-75-6-1267.


Budgerigar fledgling disease virus (BFDV) represents the first non-mammalian member of the polyomavirus genus and possesses uncommon structural and biological properties. Recombinant baculoviruses were constructed to express BFDV small t antigen, large T antigens, as well as a large T deletion mutant Td and beta-galactosidase-Td fusion proteins to high levels in infected insect cells. A recombinant virus containing a genomic copy of the BFDV early region was used for small t antigen expression, and corresponding intron-deleted cDNAs for production of large T antigen derivatives. Recombinant T as well as authentic T antigen proteins from infected chicken embryo fibroblasts were purified using both immunoaffinity and DNA affinity column chromatography. We present evidence that the large T antigen interacts specifically with DNA sequences present in the non-coding region of BFDV; by indirect DNA immunoprecipitation mapping and DNase I footprinting, four regions including 12 DNA-binding sites have been determined that cover most of the BFDV non-coding region. The T antigen binding pattern observed suggests a protein-DNA interaction system considerably different from those of simian virus 40 and other polyomaviruses.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antigens, Polyomavirus Transforming / genetics*
  • Base Sequence
  • Binding Sites
  • Birds / microbiology
  • Cell Compartmentation
  • DNA-Binding Proteins / metabolism
  • Gene Expression Regulation, Viral*
  • Molecular Sequence Data
  • Molecular Weight
  • Moths
  • Nucleopolyhedroviruses / genetics
  • Polyomavirus / genetics*
  • Recombinant Proteins
  • Regulatory Sequences, Nucleic Acid
  • Restriction Mapping
  • Sequence Alignment
  • Sequence Homology, Nucleic Acid


  • Antigens, Polyomavirus Transforming
  • DNA-Binding Proteins
  • Recombinant Proteins