|
|
||||||||
1 Virology Group, Molecular Biology Sector, Biotechnology Research Institute, National Research Council of Canada, 6100 Royalmount Avenue, Montréal, Québec, Canada H4P 2R2
2 Department of Microbiology and Immunology, McGill University, 3775 University Street, Montréal, Québec, Canada H3A 2B4
and3 Forest Pest Management Institute, Forestry Canada, 1219 Queen St. East, Sault Ste. Marie, Ontario, Canada P6A 5M7
The entomopoxviruses (insect poxviruses) of eastern spruce budworm (Choristoneura fumiferana), two year cycle spruce budworm (C. biennis) and the Indian red army worm (Amsacta moorei) are being studied in our laboratory for their potential as biological insecticides and expression vectors. These viruses characteristically replicate in the cytoplasm of insect cells and produce occlusion bodies that serve to protect the virion from the environment. By analogy to mammalian pox-viruses, they should also contain a viral thymidine kinase (TK) that functions in viral DNA synthesis. The replication of the A. moorei entomopoxvirus was inhibited by bromodeoxyuridine whereas the baculovirus of Autographa californica was insensitive to this drug. This result was a biochemical indication that entomopoxviruses contained a kinase that phosphorylated this nucleoside analogue and thus viral DNA synthesis was inhibited. TK genes from the three different insect poxviruses were identified, cloned and sequenced. The sequences of the TK genes of the entomopoxviruses were closely related and exhibited 63.2% identity and 9.9% similarity at the protein level. However, there was only 36.7% identity and 13.6% similarity when these enzymes were compared to their mammalian poxvirus counterpart in vaccinia virus. Finally, one entomopoxvirus TK gene was expressed in Escherichia coli mutants lacking the enzyme. These bacteria were converted to a phenotype that could incorporate radioactive thymidine into their chromosomal DNA. The results presented in this paper provide impetus for the design of a recombinant entomopoxvirus expression system in which foreign genes could be introduced into the viral TK locus under selective pressure from bromodeoxyuridine.
Received 2 April 1992;
accepted 26 August 1992.
This article has been cited by other articles:
![]() |
C. L. Afonso, E. R. Tulman, Z. Lu, E. Oma, G. F. Kutish, and D. L. Rock The Genome of Melanoplus sanguinipes Entomopoxvirus J. Virol., January 1, 1999; 73(1): 533 - 552. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| INT J SYST EVOL MICROBIOL | MICROBIOLOGY | J GEN VIROL |
| J MED MICROBIOL | ALL SGM JOURNALS | |