Inhibition of protein kinase C promotes dengue virus replication

Noppakunmongkolchai, Warobon; Poyomtip, Teera; Jittawuttipoka, Thichakorn; Luplertlop, Natthanej; Sakuntabhai, Anavaj; Chimnaronk, Sarin; Jirawatnotai, Siwanon; Tohtong, Rutaiwan

doi:10.1186/s12985-016-0494-6

Cited by 26 publications

(17 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In addition to MAPKs, curcumin has been demonstrated to modulate the activity of various protein kinases [ 39 , 40 ]. In addition to maintaining physiological homeostasis, PKC has been implicated in the replication of dengue virus [ 41 , 42 ]. Furthermore, PKCδ affects HIV replication via modulation of the post-entry step [ 43 ].…”

Section: Discussionmentioning

confidence: 99%

Inhibition of EV71 by curcumin in intestinal epithelial cells

2018

View full text Add to dashboard Cite

EV71 is a positive-sense single-stranded RNA virus that belongs to the Picornaviridae family. EV71 infection may cause various symptoms ranging from hand-foot-and-mouth disease to neurological pathological conditions such as aseptic meningitis, ataxia, and acute transverse myelitis. There is currently no effective treatment or vaccine available. Various compounds have been examined for their ability to restrict EV71 replication. However, most experiments have been performed in rhabdomyosarcoma or Vero cells. Since the gastrointestinal tract is the entry site for this pathogen, we anticipated that orally ingested agents may exert beneficial effects by decreasing virus replication in intestinal epithelial cells. In this study, curcumin (diferuloylmethane, C21H20O6), an active ingredient of turmeric (Curcuma longa Linn) with anti-cancer properties, was investigated for its anti-enterovirus activity. We demonstrate that curcumin treatment inhibits viral translation and increases host cell viability. Curcumin does not exert its anti-EV71 effects by modulating virus attachment or virus internal ribosome entry site (IRES) activity. Furthermore, curcumin-mediated regulation of mitogen-activated protein kinase (MAPK) signaling pathways is not involved. We found that protein kinase C delta (PKCδ) plays a role in virus translation in EV71-infected intestinal epithelial cells and that curcumin treatment decreases the phosphorylation of this enzyme. In addition, we show evidence that curcumin also limits viral translation in differentiated human intestinal epithelial cells. In summary, our data demonstrate the anti-EV71 properties of curcumin, suggesting that ingestion of this phytochemical may protect against enteroviral infections.

show abstract

Section: Discussionmentioning

confidence: 99%

Inhibition of EV71 by curcumin in intestinal epithelial cells

2018

View full text Add to dashboard Cite

show abstract

“…PKC phosphorylation of the C viral protein has been described as the key regulator of apoptosis induction during infection [ 25 ], and inhibition of all PKC isoforms affected WNV entry into mosquito cells [ 26 ]. Conversely, DENV replication was enhanced after in vitro inhibition with bisindlolylmaleinmide I (Bis I), a specific chemical inhibitor of classical and novel PKCs [ 17 ]. In our study, both calphostin C and chelerythrine decreased the amount of RNA released to the culture medium and of dsRNA intermediates formation, even though the observed reduction was significantly higher when chelerythrine was used.…”

Section: Discussionmentioning

confidence: 99%

“…Apart from this role of PKCs in the control of cell biology, both in silico and in vitro analyses performed with DENV indicated that the flaviviral RNA-dependent RNA polymerase (NS5) contains four potential phosphorylation sites for PKC that are involved in the modulation of the viral replication. Three out of these four sites (Thr302, Ser796, and Ser885, according to DENV2 strain, Genbank AHG23127) are present in WNV, two of them (Thr302 and Ser796) being conserved in all vector-borne flaviviruses [ 17 ]. Phosphorylation of flavivirus NS5 has been widely reported [ 18 , 19 , 20 , 21 , 22 ].…”

Section: Introductionmentioning

confidence: 99%

“…Moreover, certain lipids required for the activation of atypical PKCs [ 23 ], such as ceramides, are increased in WNV-infected cells [ 24 ], pointing to a role of PKCs during WNV infection. However, previous studies with WNV and other flaviviruses reported conflicting results and did not evaluate the specific role of PKCs [ 17 , 25 , 26 ].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Pharmacological Inhibition of Protein Kinase C Reduces West Nile Virus Replication

Blázquez¹,

Vázquez-Calvo²,

Martín-Acebes³

et al. 2018

Viruses

View full text Add to dashboard Cite

Flaviviruses are relevant animal and human pathogens that include West Nile virus (WNV), Japanese encephalitis virus, dengue virus, or Zika virus, among others. Currently, no licensed therapy is available to fight flaviviral infections. Protein kinases C (PKCs) constitute a family of multifunctional lipid-dependent isoenzymes that regulate a wide variety of cellular processes (apoptosis, differentiation, proliferation, cellular transformation, motility, adhesion, etc.) being currently considered at the front line of drug development for the treatment of diverse human disorders. PKCs have also been implicated in different steps during viral replication; however, nowadays, results regarding their role in flavivirus replication are controversial. Here we demonstrate that calphostin C and chelerythrine, two broad-PKC inhibitors that target conventional, novel and atypical PKCs, significantly inhibit WNV multiplication in cell culture without affecting cell viability. A reduction of viral yields was observed in treated cells when compared with mock-treated cells. Likewise, immunofluorescence detection of viral enveloped E protein was reduced in treated cells, as was the amount of viral RNA released to the supernatant, mainly in those treated with chelerythrine. On the other hand, two PKC inhibitors specific for conventional and novel isoforms (staurosporine and enzastaurine) did not show any significant effect in WNV multiplication. These results suggested that PKCs, more probably atypical PKCs, are likely involved in WNV multiplication, although both broad-spectrum tested drugs seem to act through different mechanisms, and point to them as potential antiviral candidates for WNV, as well as for other related flaviviruses.

show abstract

“…The role of phosphorylation of viral proteins in the viral live cycle has been increasingly recognized, as demonstrated for multiple viruses, including influenza A virus (39), Newcastle disease virus (40), hepatitis C virus (41), dengue virus (42), and Rift valley virus (43), among others. While phosphatases are involved in multiple normal physiological reactions of cells, targeting of their noncatalytic sites, which prevents their interaction with only certain substrates, including viral proteins, may be a viable approach to develop broadly specific antivirals.…”

Section: Discussionmentioning

confidence: 99%

Phosphorylated VP30 of Marburg Virus Is a Repressor of Transcription

Tigabu

Ramanathan

Ivanov

et al. 2018

J Virol

View full text Add to dashboard Cite

The filoviruses Marburg (MARV) and Ebola (EBOV) cause hemorrhagic fever in humans and non-human primates with case high fatality rates. MARV VP30 is known to be phosphorylated and to interact with nucleoprotein (NP), but its role in regulation of viral transcription is disputed. Here we analyzed phosphorylation of VP30 by mass spectrometry, which resulted in identification of multiple phosphorylated amino acids. Modeling full-length three-dimensional structure of VP30 and mapping the identified phosphorylation sites showed that all sites lie in disordered regions mostly in the N-terminal domain of the protein. Minigenome analysis of the identified phosphorylation sites demonstrated that phosphorylation at amino acid residues 46-53 inhibits transcription. To test the effect of VP30 phosphorylation on its interaction with other MARV proteins, co-immunoprecipitation analyses were performed. They demonstrated the involvement of VP30 phosphorylation in interaction with two other proteins of the MARV ribonucleoprotein complex, NP and VP35. To identify the role of protein phosphatase 1 (PP1) in the identified effects, a small molecule 1E7-03 targeting a non-catalytic site of the enzyme, which previously showed to increase EBOV VP30 phosphorylation, was used. Treatment of cells with 1E7-03 increased phosphorylation of VP30 at the cluster of phosphorylated amino acids Ser-46-Thr-53, reduced transcription of MARV minigenome, enhanced binding to NP and VP35 and dramatically reduced replication of infectious MARV particles. Thus MARV VP30 phosphorylation can be targeted for development of future antivirals such as PP1-targeting compounds. The largest outbreak of MARV occurred in Angola in 2004-2005 and caused 90% case fatality rate. There are no approved treatments available for MARV. Development of antivirals as therapeutics requires fundamental understanding of the viral life cycle. Because of the close similarity of MARV to another member of family, EBOV, it was assumed that the two viruses have similar mechanisms of regulation of transcription and replication. Here, characterization of the role of VP30 and its phosphorylation sites in transcription of MARV genome demonstrated differences compared to EBOV. The identified phosphorylation sites appeared to inhibit transcription, and appeared to be involved in interaction with both NP and VP35 ribonucleoproteins. A small molecule targeting PP1 inhibited transcription of MARV genome, effectively suppressing replication of the viral particles. These data demonstrate the possibility of development of antivirals based on compounds targeting PP1.

show abstract

Inhibition of protein kinase C promotes dengue virus replication

Cited by 26 publications

References 33 publications

Inhibition of EV71 by curcumin in intestinal epithelial cells

Inhibition of EV71 by curcumin in intestinal epithelial cells

Pharmacological Inhibition of Protein Kinase C Reduces West Nile Virus Replication

Phosphorylated VP30 of Marburg Virus Is a Repressor of Transcription

Contact Info

Product

Resources

About