title: Defining the roles of the baculovirus regulatory proteins IE0 and IE1 in genome replication and early gene transactivation.
abstract: IE0 and IE1 of the baculovirus Autographa californica multiple nucleopolyhedrovirus are essential transregulatory proteins required for both viral DNA replication and transcriptional transactivation. IE0 is identical to IE1 except for 54 amino acids at the N-terminus but the functional differences between these two proteins remain unclear. The purpose of this study was to determine the separate roles of these critical proteins in the virus life cycle. Unlike prior studies, IE0 and IE1 were analyzed using viruses that expressed ie0 and ie1 from an identical promoter so that the timing and levels of expression were comparable. IE0 and IE1 were found to equally support viral DNA replication and budded virus (BV) production. However, specific viral promoters were selectively transactivated by IE0 relative to IE1 but only when expressed at low levels. These results indicate that IE0 preferentially transactivates specific viral genes at very early times post-infection enabling accelerated replication and BV production.
authors.affiliation: Department of Biology, University of British Columbia, Kelowna, British Columbia, Canada V1V 1V7.
authors.forename: Nadia
authors.initials: N
authors.lastname: Sokal
authors.affiliation: Pacific Agri-Food Research Centre, AAFC, Summerland, British Columbia, Canada V0H 1Z0.
authors.forename: Yingchao
authors.initials: Y
authors.lastname: Nie
authors.affiliation: Pacific Agri-Food Research Centre, AAFC, Summerland, British Columbia, Canada V0H 1Z0.
authors.forename: Leslie G
authors.initials: LG
authors.lastname: Willis
authors.affiliation: Boyce Thompson Institute at Cornell University, Ithaca, New York, 14853-1801 USA.
authors.forename: Junya
authors.initials: J
authors.lastname: Yamagishi
authors.affiliation: Boyce Thompson Institute at Cornell University, Ithaca, New York, 14853-1801 USA.
authors.forename: Gary W
authors.initials: GW
authors.lastname: Blissard
authors.affiliation: Department of Biology, University of British Columbia, Kelowna, British Columbia, Canada V1V 1V7.
authors.forename: Mark R
authors.initials: MR
authors.lastname: Rheault
authors.affiliation: Pacific Agri-Food Research Centre, AAFC, Summerland, British Columbia, Canada V0H 1Z0; Department of Biology, University of British Columbia, Kelowna, British Columbia, Canada V1V 1V7. Electronic address: david.theilmann@agr.gc.ca.
authors.forename: David A
authors.initials: DA
authors.lastname: Theilmann
mesh_terms: D000818:Animals; D016367:Baculoviridae / Q000378:metabolism*; D002460:Cell Line; D015967:Gene Expression Regulation, Viral / Q000502:physiology*; D017874:Immediate-Early Proteins / Q000235:genetics / Q000378:metabolism*; D009036:Moths / Q000166:cytology; D010957:Plasmids; D015534:Trans-Activators / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic; D015533:Transcriptional Activation; D014779:Virus Replication / Q000502:physiology*
chemical_list: D017874:Immediate-Early Proteins; D015534:Trans-Activators; C450080:ie0 protein, baculovirus
keywords: AcMNPV; Baculovirus; DNA replication; Gene expression; IE0; IE1; Transactivation; Transcription factor