A Novel Spliced Transcript of Influenza A/WSN/33 Virus

It has been shown that influenza A virus M1 mRNA has two alternative 5′ splice sites: a distal 5′ splice site producing M3 mRNA that has the coding potential for 9 amino acids and a proximal 5′ splice site producing M2 mRNA that encodes the essential M2 ion-channel protein. In this study, we demonstrated that the laboratory widely used strain A/WSN/33, but not A/Udorn/72 possessed another novel 5′ splice site producing a transcript with the coding potential for 54 amino acids. We nominated this novel transcript as M4 mRNA. M4 mRNA was detected in A/WSN/33-infected cells derived from different species. Sequence comparison of M1 mRNA in both A/WSN/33 and Udorn/72 at position 143 to 151 reveals that this novel 5′ splice site generated in WSN was due to one nucleotide difference at position 147. Several strains of influenza A viruses other than WSN also possess the potential M4 5′ splice site by sequence analysis from the files of GenBank.

[1]  R. Krug,et al.  Novel exploitation of a nuclear function by influenza virus: the cellular SF2/ASF splicing factor controls the amount of the essential viral M2 ion channel protein in infected cells. , 1996, The EMBO journal.

[2]  O. Fletcher,et al.  Comparative pathology of chickens experimentally inoculated with avian influenza viruses of low and high pathogenicity. , 1997, Avian diseases.

[3]  F. Sanger,et al.  DNA sequencing with chain-terminating inhibitors. , 1977, Proceedings of the National Academy of Sciences of the United States of America.

[4]  R. Lamb,et al.  Sequences of mRNAs derived from genome RNA segment 7 of influenza virus: colinear and interrupted mRNAs code for overlapping proteins. , 1981, Proceedings of the National Academy of Sciences of the United States of America.

[5]  P. Sharp,et al.  Splicing of messenger RNA precursors. , 1987, Cold Spring Harbor symposia on quantitative biology.

[6]  R. Lamb,et al.  Conservation of the influenza virus membrane protein (M1) amino acid sequence and an open reading frame of RNA segment 7 encoding a second protein (M2) in H1N1 and H3N2 strains. , 1981, Virology.

[7]  R. Lamb.  Genes and Proteins of the Influenza Viruses , 1989 .

[8]  M. Gething,et al.  Influenza virus RNA segment 7 has the coding capacity for two polypeptides. , 1980, Virology.

[9]  R. Lamb,et al.  Influenza A virus M2 protein: monoclonal antibody restriction of virus growth and detection of M2 in virions , 1988, Journal of virology.

[10]  R. Lamb,et al.  Effects of antibody to the influenza A virus M2 protein on M2 surface expression and virus assembly. , 1995, Virology.

[11]  S. Fields,et al.  Cloning of influenza cDNA ino M13: the sequence of the RNA segment encoding the A/PR/8/34 matrix protein. , 1980, Nucleic acids research.

[12]  R. Krug,et al.  The choice of alternative 5' splice sites in influenza virus M1 mRNA is regulated by the viral polymerase complex. , 1995, Proceedings of the National Academy of Sciences of the United States of America.

[13]  P. Reading,et al.  Changes in the hemagglutinin molecule of influenza type A (H3N2) virus associated with increased virulence for mice , 1997, Archives of Virology.

[14]  J. Valcárcel,et al.  Splicing of influenza virus matrix protein mRNA expressed from a simian virus 40 recombinant. , 1993, The Journal of general virology.

[15]  R. Lamb,et al.  Spliced and unspliced messenger RNAs synthesized from cloned influenza virus M DNA in an SV40 vector: expression of the influenza virus membrane protein (M1). , 1982, Virology.

[16]  R. Lamb,et al.  Influenza virus M2 protein is an integral membrane protein expressed on the infected-cell surface , 1985, Cell.

[17]  Lawrence H. Pinto,et al.  Influenza virus M2 protein has ion channel activity , 1992, Cell.