J Bacteriol Virol.  2012 Dec;42(4):368-371. 10.4167/jbv.2012.42.4.368.

A Novel PA-X Protein Translated from Influenza A Virus Segment 3

• Lee I
• Kim JI
• Park MS

• KMID: 2168675
• DOI: http://doi.org/10.4167/jbv.2012.42.4.368

Abstract

The pathogenicity of influenza A viruses is a multigenic trait, which is orchestrated by the global networks between eight viral genomic constituents and their cellular interacting partners. A recent report provided information on the finding of a new PA ribosomal frameshifting product, the PA-X protein, in the influenza A virus segment 3, and an endonuclease property was suggested for a possible role of the PA-X protein. In cultured cells, viral growth was not affected by the PA-X protein expression. However, the reduced pathogenicity of mice appeared to be closely associated with the PA-X protein expression. It was also revealed that the PA-X protein was able to modulate host gene expression. Considered together, the PA-X protein can be a cellular signaling modulator and subsequently control viral pathogenicity. By reviewing recent publications, we present new insights in the contribution of the PA-X protein to the cellular signaling network and the resultant viral pathogenicity.

Keyword

Influenza; Endonuclease activity; Pathogenicity; PA-X; Ribosomal frameshift

MeSH Terms

Animals
Cells, Cultured
Frameshifting, Ribosomal
Gene Expression
Influenza A virus
Influenza, Human
Mice

Figure

• 

  Figure 1 Multiple proteins are expressed from a single gene of influenza A virus. (A) The M2 and NS2 proteins are expressed by gene splicing. (B) The PB1-F2 protein is encoded from overlapped frame. (C) The PA-X protein is expressed by +1 ribosomal frameshifting. (D) 'UCC UUU CGU C' motif in PA gene is related with ribosomal frameshifting.

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