Modulation of influenza virus replication by alteration of sodium ion transport and protein kinase C activity

Hoffmann, Hans-Heinrich; Palese, Peter; Shaw, Megan L.

doi:10.1016/j.antiviral.2008.05.008

Cited by 87 publications

(80 citation statements)

References 47 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…A similar approach was described very recently by Hoffmann et al (2008). The assay system allowed us to quantify on the one hand the replication efficiency of influenza A virus and on the other hand the intracellular activity of a reconstituted viral RNA polymerase complex.…”

mentioning

confidence: 99%

Influenza A virus proteins PB1 and NS1 are subject to functionally important phosphorylation by protein kinase C

Mahmoudian

Auerochs

Gröne

et al. 2009

Journal of General Virology

View full text Add to dashboard Cite

The virulence of influenza A viruses depends on the activity of the viral RNA polymerase complex and viral regulatory phosphoproteins. We identified that the protein kinase C (PKC) inhibitor Gö 6976 had a post-entry anti-influenza viral effect, by using a polymerase activity-based reporter assay. This inhibitory effect was observed for influenza virus-infected cells as well as for cells transiently transfected with constructs for the RNA polymerase complex. Importantly, the in vitro analysis of viral protein phosphorylation identified PKCa as a kinase phosphorylating PB1 and NS1, but not PB2, PA or NP. Gö 6976 was able to block PKC-specific phosphorylation in vitro. Thus, our data suggest that PKC contributes to the phosphorylation of influenza PB1 and NS1 proteins which appears to be functionally relevant for both viral RNA polymerase activity and efficient viral replication.Influenza A viruses are pathogens that cause significant morbidity and mortality in humans and a variety of animal species (Palese & Shaw, 2007;Wright et al., 2007). Influenza viruses possess a segmented negative-sense RNA genome which is replicated in the nucleus of infected cells. The virulence of individual virus strains is based on a complex co-action of determinants, including the viral haemagglutinin (HA), the RNA-dependent RNA polymerase (subunits PB1, PB2 and PA) and the nonstructural protein (NS1) (Geiss et al., 2002;Tumpey et al., 2005Tumpey et al., , 2007. The RNA-dependent RNA polymerase complex is responsible for both transcription and genomic replication (Torreira et al., 2007;Palese & Shaw, 2007). PB1 represents the central catalytic subunit of the polymerase complex (Honda & Ishihama, 1997;Poch et al., 1989;Torreira et al., 2007), PB2 is responsible for recognition and binding of the cap structures of host mRNAs which are used for priming viral transcription (Fechter & Brownlee, 2005;Guilligay et al., 2008), while PA combines essential activities required for genome replication and protein processing (Fodor & Smith, 2004;Maier et al., 2008;Palese & Shaw, 2007). The viral nucleoprotein (NP) strictly associates with the RNA polymerase complex to form viral ribonucleoproteins (RNPs) (Noda et al., 2006;Portela & Digard, 2002), it stimulates RNA polymerase activity and mediates nuclear RNP translocation (Neumann et al., 1997;Bui et al., 2002;Portela & Digard, 2002). The viral regulatory protein NS1 provides a number of functions required for efficient replication and gene expression (Hale et al., 2008a). An interaction between NS1 and the viral transcription-replication complex was reported (Marion et al., 1997) but awaits a confirmation in functional aspects. NS1 and the RNP components including NP are phosphoproteins in various types and strains of influenza viruses (Sanz-Ezquerro et al., 1998;Bui et al., 2002;Arrese & Portela, 1996;Skorko et al., 1991;Marschall et al., 1999;Neumann et al., 1997;Privalsky & Penhoet, 1978, 1981. Several cellular protein kinases, including protein kinase C (PKC), casein kinase II, cyclin-dependen...

show abstract

mentioning

confidence: 99%

Influenza A virus proteins PB1 and NS1 are subject to functionally important phosphorylation by protein kinase C

Mahmoudian

Auerochs

Gröne

et al. 2009

Journal of General Virology

View full text Add to dashboard Cite

show abstract

“…Here we report that the small-molecular-weight compound A3, which was identified in a previously reported influenza virus high-throughput screen (27), possesses broad-spectrum activity against RNA-, DNA-, and retroviruses and acts by targeting pyrimidine metabolism.…”

mentioning

confidence: 99%

“…A549 cells were transfected with expression plasmids for the influenza virus polymerase proteins (PB1, PB2, and PA), the nucleoprotein (NP), and the previously described influenza virus-specific firefly luciferase reporter (27). To normalize for transfection efficiency, a Renilla luciferase plasmid was cotransfected.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Broad-spectrum antiviral that interferes with de novo pyrimidine biosynthesis

Hoffmann

Kunz

Simon

et al. 2011

Proc. Natl. Acad. Sci. U.S.A.

226

207

View full text Add to dashboard Cite

Compound A3 was identified in a high-throughput screen for inhibitors of influenza virus replication. It displays broad-spectrum antiviral activity, and at noncytotoxic concentrations it is shown to inhibit the replication of negative-sense RNA viruses (influenza viruses A and B, Newcastle disease virus, and vesicular stomatitis virus), positive-sense RNA viruses (Sindbis virus, hepatitis C virus, West Nile virus, and dengue virus), DNA viruses (vaccinia virus and human adenovirus), and retroviruses (HIV). In contrast to mammalian cells, inhibition of viral replication by A3 is absent in chicken cells, which suggests species-specific activity of A3. Correspondingly, the antiviral activity of A3 can be linked to a cellular protein, dihydroorotate dehydrogenase (DHODH), which is an enzyme in the de novo pyrimidine biosynthesis pathway. Viral replication of both RNA and DNA viruses can be restored in the presence of excess uracil, which promotes pyrimidine salvage, or excess orotic acid, which is the product of DHODH in the de novo pyrimidine biosynthesis pathway. Based on these findings, it is proposed that A3 acts by depleting pyrimidine pools, which are crucial for efficient virus replication.

show abstract

“…The cell could be attempting to contain the viral infection through various means that inadvertently result in untoward effects, such as pulmonary edema. It is possible that mechanisms developed to purposefully increase intracellular sodium concentrations, which have been found to inhibit viral replication (18). However, AMPK also attenuates ENaC function and may counterbalance the effects on Na,K-ATPase to minimize the changes to intracellular sodium concentrations (19).…”

Section: Discussionmentioning

confidence: 99%