Characterization of a protein kinase activity associated with purified capsids of the granulosis virus infecting Plodia interpunctella

Wilson, Marijo E.; Consigli, Richard A.

doi:10.1016/0042-6822(85)90390-3

Cited by 58 publications

(30 citation statements)

References 26 publications

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“…A similar case also has been reported in another study on VP12, the P6.9 ortholog in Plodia interpunctella granulovirus (PiGV). In VP12, the phosphorylation of Arg residues could be detected by nuclear magnetic resonance but not by phosphoamino acid analysis, in which the protein was degraded in a low-pH solution (58).…”

Section: Discussionmentioning

confidence: 99%

Posttranslational Modifications of Baculovirus Protamine-Like Protein P6.9 and the Significance of Its Hyperphosphorylation for Viral Very Late Gene Hyperexpression

Zhao

Lai

et al. 2015

J Virol

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Many viruses utilize viral or cellular chromatin machinery for efficient infection. Baculoviruses encode a conserved protaminelike protein, P6.9. This protein plays essential roles in various viral physiological processes during infection. However, the mechanism by which P6.9 regulates transcription remains unknown. In this study, 7 phosphorylated species of P6.9 were resolved in Sf9 cells infected with the baculovirus type species Autographa californica multiple nucleopolyhedrovirus (AcMNPV). Mass spectrometry identified 22 phosphorylation and 10 methylation sites but no acetylation sites in P6.9. Immunofluorescence demonstrated that the P6.9 and virus-encoded serine/threonine kinase PK1 exhibited similar distribution patterns in infected cells, and coimmunoprecipitation confirmed the interaction between them. Upon pk1 deletion, nucleocapsid assembly and polyhedron formation were interrupted and the transcription of viral very late genes was downregulated. Interestingly, we found that the 3 most phosphorylated P6.9 species vanished from Sf9 cells transfected with the pk1 deletion mutant, suggesting that PK1 is involved in the hyperphosphorylation of P6.9. Mass spectrometry suggested that the phosphorylation of the 7 Ser/Thr and 5 Arg residues in P6.9 was PK1 dependent. Replacement of the 7 Ser/Thr residues with Ala resulted in a P6.9 phosphorylation pattern similar to that of the pk1 deletion mutant. Importantly, the decreases in the transcription level of viral very late genes and viral infectivity were consistent. Our findings reveal that P6.9 hyperphosphorylation is a precondition for the maximal hyperexpression of baculovirus very late genes and provide the first experimental insights into the function of the baculovirus protaminelike protein and the related protein kinase in epigenetics. IMPORTANCEDiverse posttranslational modifications (PTMs) of histones constitute a code that creates binding platforms that recruit transcription factors to regulate gene expression. Many viruses also utilize host-or virus-induced chromatin machinery to promote efficient infections. Baculoviruses encode a protamine-like protein, P6.9, which is required for a variety of processes in the infection cycle. Currently, P6.9's PTM sites and its regulating factors remain unknown. Here, we found that P6.9 could be categorized as unphosphorylated, hypophosphorylated, and hyperphosphorylated species and that a virusencoded serine/threonine kinase, PK1, was essential for P6.9 hyperphosphorylation. Abundant PTM sites on P6.9 were identified, among which 7 Ser/Thr phosphorylated sites were PK1 dependent. Mutation of these Ser/Thr sites reduced very late viral gene transcription and viral infectivity, indicating that the PK1-mediated P6.9 hyperphosphorylation contributes to viral proliferation. These data suggest that a code exists in the sophisticated PTM of viral protamine-like proteins and participates in viral gene transcription. In eukaryotic cells, genomic DNA is packaged into nucleosomes, the structural unit of chromatin, b...

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Section: Discussionmentioning

confidence: 99%

Posttranslational Modifications of Baculovirus Protamine-Like Protein P6.9 and the Significance of Its Hyperphosphorylation for Viral Very Late Gene Hyperexpression

Zhao

Lai

et al. 2015

J Virol

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“…Based on genome sequence analyses, the existence of a viral protein kinase in Anagrapha falcifera multinuclear polyhedrosis virus (AfMNPV) and Neodiprion lecontei nucleopolyhedrovirus (NeleNPV) was also predicted (64,113). Baculovirus kinase activity was first suggested to be essential for release of viral DNA from virions during entry (230,231). More recently, PK1 has been shown to regulate transcription from very late promoters, such as the polyhedrin (polh) and p10 promoters.…”

Section: Baculovirusesmentioning

confidence: 99%

Viral Serine/Threonine Protein Kinases

Jacob

Broeke

Favoreel

2011

J Virol

109

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Phosphorylation represents one the most abundant and important posttranslational modifications of proteins, including viral proteins. Virus-encoded serine/threonine protein kinases appear to be a feature that is unique to large DNA viruses. Although the importance of these kinases for virus replication in cell culture is variable, they invariably play important roles in virus virulence. The current review provides an overview of the different viral serine/threonine protein kinases of several large DNA viruses and discusses their function, importance, and potential as antiviral drug targets.

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“…However, almost all other studies in eukaryotes have focused on the phosphorylation of serine, threonine and tyrosine residues since partial acid hydrolysis, as used for conventional phosphoamino acid analysis, destroys the phosphoramidate bonds found in phosphohistidine, phospholysine or phosphoarginine [7]. Phosphoramidate bonds and protein kinases that phosphorylate arginine, histidine or lysine have been reported in eukaryotes [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25] and reviewed recently [26]. Saccharomyces cerevisiae contains a kinase that transfers phosphate from ATP to histidine-75 in the protein, histone H4, in vitro [27].…”

Section: Introductionmentioning

confidence: 99%

Protein histidine phosphatase activity in rat liver and spinach leaves

Matthews

MacKintosh

1995

FEBS Letters

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Whole cell extracts from rat liver or spinach leaves contain divalent ion-independent protein histidine phosphatase activity due to phosphatases of the PPIlPP2A family. In the rat liver extract, almost all the activity was found in the PP1, PP2A~ and PP2A2 peaks. In the spinach leaf extract, four phosphorylase phosphatase activity peaks were resolved --three containing PP1 and one containing PP2A --and all showed histidine phosphatase activity. Thus, protein histidine phosphatase activity is expressed in the cytosolic forms of protein phosphatases of the PPIlPP2A family in mammalian and plant cells.

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Characterization of a protein kinase activity associated with purified capsids of the granulosis virus infecting Plodia interpunctella

Cited by 58 publications

References 26 publications

Posttranslational Modifications of Baculovirus Protamine-Like Protein P6.9 and the Significance of Its Hyperphosphorylation for Viral Very Late Gene Hyperexpression

Posttranslational Modifications of Baculovirus Protamine-Like Protein P6.9 and the Significance of Its Hyperphosphorylation for Viral Very Late Gene Hyperexpression

Viral Serine/Threonine Protein Kinases

Protein histidine phosphatase activity in rat liver and spinach leaves

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