Conserved structural motifs at the C-terminus of baculovirus protein IE0 are important for its functions in transactivation and supporting hr5-mediated DNA replication

IE0 and IE1 are transactivator proteins of the most studied baculovirus, the Autographa californica multiple nucleopolyhedrovirus (AcMNPV). IE0 is a 72.6 kDa protein identical to IE1 with the exception of its 54 N-terminal amino acid residues. To gain some insight about important structural motifs o...

Full description

Saved in:
Bibliographic Details
Published in:Viruses 2012-05, Vol.4 (5), p.761-776
Main Authors: Luria, Neta, Lu, Liqun, Chejanovsky, Nor
Format: Article
Language:English
Subjects:
Ablation
Animals
Baculoviridae - physiology
baculovirus
Cell Line
Conserved Sequence
DNA Replication
Drosophila
functions
Gene Expression
Genes
Genomes
IE0 transactivator
Immediate-Early Proteins - genetics
Immediate-Early Proteins - metabolism
Infections
Insects
mutagenesis
Plasmids
Proteins
Recombinant Proteins - genetics
Recombinant Proteins - metabolism
Replication Origin
RNA polymerase
Trans-Activators - genetics
Trans-Activators - metabolism
Transcriptional Activation
Virus Replication
Viruses
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:IE0 and IE1 are transactivator proteins of the most studied baculovirus, the Autographa californica multiple nucleopolyhedrovirus (AcMNPV). IE0 is a 72.6 kDa protein identical to IE1 with the exception of its 54 N-terminal amino acid residues. To gain some insight about important structural motifs of IE0, we expressed the protein and C‑terminal mutants of it under the control of the Drosophila heat shock promoter and studied the transactivation and replication functions of the transiently expressed proteins. IE0 was able to promote replication of a plasmid bearing the hr5 origin of replication of AcMNPV in transient transfections with a battery of eight plasmids expressing the AcMNPV genes dnapol, helicase, lef-1, lef-2, lef-3, p35, ie-2 and lef-7. IE0 transactivated expression of the baculovirus 39K promoter. Both functions of replication and transactivation were lost after introduction of selected mutations at the basic domain II and helix-loop-helix conserved structural motifs in the C-terminus of the protein. These IE0 mutants were unable to translocate to the cell nucleus. Our results point out the important role of some structural conserved motifs to the proper functioning of IE0.
ISSN:1999-4915
1999-4915
DOI:10.3390/v4050761