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Conserved Structural Motifs at the C-Terminus of Baculovirus Protein IE0 are Important for its Functions in Transactivation and Supporting hr5-mediated DNA Replication

By Neta Luria, Liqun Lu and Nor Chejanovsky

Abstract

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

Topics: Article
Publisher: MDPI
OAI identifier: oai:pubmedcentral.nih.gov:3386618
Provided by: PubMed Central
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    1. A Manual of Methods for Baculovirus Vectors and Insect CellCulture Procedures; Texas Agricultural Experiment Station Bulletin: College Station,
    2. (1978). Analysis of baculovirus genomes with restriction endonucleases. Virology
    3. (2007). Baculovirus late and very late gene regulation. Curr. Drug Targets
    4. (2002). Baculovirus transregulator IE1 requires a dimeric nuclear localization element for nuclear import and promoter
    5. (1999). Characterization of baculovirus repeated open reading frames (bro) in Bombyx mori nucleopolyhedrovirus.
    6. (2002). Characterization of the apoptosis suppressor protein P49 from the Spodoptera littoralis nucleopolyhedrovirus.
    7. (1999). Colocalization of baculovirus IE-1 and two DNA-binding proteins, DBP and LEF-3, to viral replication factories.
    8. (2006). Conserved molecular systems of the Baculoviridae. Virology
    9. (1995). Differential requirements for baculovirus late expression factor genes in two cell
    10. (1995). Differential transcription of baculovirus late and very late promoters: Fractionation of nuclear extracts by phosphocellulose chromatography.
    11. (1997). DNA-dependent transregulation by IE1 of Autographa californica nuclear polyhedrosis virus: IE1 domains required for transactivation and DNA
    12. (1995). Expression of the IE1 transactivator of Autographa californica nuclear polyhedrosis virus during viral infection. Virology
    13. (2005). Focal distribution of baculovirus IE1 triggered by its binding to the hr DNA
    14. (1994). Functional dissection of the Autographa californica nuclear polyhedrosis virus enhancer element hr5. Virology
    15. (1988). Functional mapping of an AcNPV immediately early gene which augments expression of the IE-1 trans-activated 39K gene. Virology
    16. (1994). Identification of genes involved in DNA replication of the Autographa californica baculovirus.
    17. (1991). Identification of spliced baculovirus RNAs expressed late in infection. Virology
    18. (1997). Identification of two independent transcriptional activation domains in the Autographa californica multicapsid nuclear polyhedrosis virus IE1
    19. (1986). Interspersed homologous DNA of Autographa californica nuclear polyhedrosis virus enhances delayed-early gene expression.
    20. (1988). Multiple early transcripts and splicing of the Autographa californica nuclear polyhedrosis virus IE-1
    21. (2006). New measures of insecticidal efficacy and safety obtained with the 39K promoter of a recombinant baculovirus. FEBS Lett.
    22. (1991). Novel regulatory properties of the IE1 and IE0 transactivators encoded by the baculovirus Autographa californica multicapsid nuclear polyhedrosis virus.
    23. (1987). Nucleotide sequence and temporal expression of a baculovirus regulatory
    24. (2001). Oligomerization mediated by a helix-loop-helix-like domain of baculovirus IE1 is required for early promoter transactivation.
    25. (2003). Reduced expression of the immediate-early protein IE0 enables efficient replication of Autographa californica multiple nucleopolyhedrovirus in poorly permissive Spodoptera littoralis cells.
    26. (1997). Regulation of baculovirus early gene expression.
    27. (1992). Regulation of delayed-early gene transcription by dual TATA boxes.
    28. (2006). Response of immunocompetent and immunosuppressed Spodoptera littoralis larvae to baculovirus infection.
    29. (2004). Role of AcMNPV IE0 in baculovirus very late gene activation. Virology
    30. (2002). The acidic activation domain of the baculovirus transactivator IE1 contains a virus specific domain essential for DNA-replication.
    31. (2004). The acidic activation domains of the baculovirus transactivators IE1 and IE0 are functional for transcriptional activation in both insect and mammalian
    32. (2005). The Autographa californica multiple nucleopolyhedrovirus ie0-ie1 gene complex is essential for wild-type virus replication, but either IE0 or IE1 can support virus
    33. (1995). The Autographa californica nuclear polyhedrosis virus homologous region 1a: Identical sequences are essential for DNA replication activity and transcriptional enhancer function. Virology
    34. (2001). The baculovirus transcriptional transactivator ie0 produces multiple products by internal initiation of translation. Virology
    35. (1998). The early baculovirus he65 promoter: On the mechanism of transcriptional activation by IE1. Virology
    36. (2003). The highly conserved basic domain I of baculovirus IE1 is required for hr enhancer DNA binding and hr-dependent
    37. (2005). The immediate-early protein IE0 of the Autographa californica nucleopolyhedrovirus is not essential for viral replication.
    38. (1995). The roles of eighteen baculovirus late expression factor genes in transcription and DNA
    39. (1993). Three baculovirus genes involved in late and very late gene expression: ie-1, ie-n, and lef-2.
    40. (2009). Transactivator IE1 is required for baculovirus early replication events that trigger apoptosis in permissive and nonpermissive
    41. (1995). Transcriptional enhancer activity of hr5 requires dual-palindrome half sites that mediate binding of a dimeric form of the baculovirus transregulator IE1.

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