Mutations that confer genetic stability to additional genes in influenza viruses

A plurality of influenza A virus vectors for preparing a reassortant influenza virus comprising:

• a) a vector for influenza A virus vRNA production comprising a promoter operably linked to an influenza A virus PA DNA linked to a transcription termination sequence, a vector for influenza A virus vRNA production comprising a promoter operably linked to an influenza A virus PB1 DNA linked to a transcription termination sequence, a vector for influenza A virus vRNA production comprising a promoter operably linked to an influenza A virus PB2 DNA linked to a transcription termination sequence, a vector for influenza A virus vRNA production comprising a promoter operably linked to an influenza A virus HA DNA linked to a transcription termination sequence, a vector for influenza A virus vRNA production comprising a promoter operably linked to an influenza A virus NP DNA linked to a transcription termination sequence, a vector for influenza A virus vRNA production comprising a promoter operably linked to an influenza A virus NA DNA linked to a transcription termination sequence, a vector for influenza A virus vRNA production comprising a promoter operably linked to an influenza A virus M DNA linked to a transcription termination sequence, and a vector for influenza A virus vRNA production comprising a promoter operably linked to an influenza A virus NS cDNA linked to a transcription termination sequence, wherein the PB1, PB2, PA, NP, NS, and M DNAs in the vectors for vRNA production encode at least one of:
• PA with a residue at position 443 that is not arginine, PB1 with a residue at position 737 that is not lysine, PB2 with a residue at position 25 that is not valine or a residue at position 712 that is not glutamic acid, NS1 with a residue at position 167 that is not proline, or HA with a residue at position 380 that is not threonine, wherein the position 443 in the PA corresponds to position 443 in a PA encoded by SEQ ID NO:1, wherein the position 737 in the PB1 corresponds to position 737 in a PB1 encoded by SEQ ID NO:2, wherein the position 25 or 712 in the PB2 corresponds to position 25 or 712 in a PB2 encoded by SEQ ID NO:3, or wherein the position 167 in the NS1 corresponds to position 167 in a NS1 encoded by SEQ ID NO:6, and wherein the HA DNA and NA DNA are from a different influenza A virus isolate relative to a virus having SEQ ID Nos. 1-6;
• and optionally
• b) a vector for mRNA production comprising a promoter operably linked to a DNA segment encoding influenza A virus PA, a vector for mRNA production comprising a promoter operably linked to a DNA segment encoding influenza A virus PB1, a vector for mRNA production comprising a promoter operably linked to a DNA segment encoding influenza A virus PB2, and a vector for mRNA production comprising a promoter operably linked to a DNA segment encoding influenza A virus NP, and optionally a vector for mRNA production comprising a promoter operably linked to a DNA segment encoding influenza A virus HA, a vector for mRNA production comprising a promoter operably linked to a DNA segment encoding influenza A virus NA, a vector for mRNA production comprising a promoter operably linked to a DNA segment encoding influenza virus M1, a vector for mRNA production comprising a promoter operably linked to a DNA segment encoding influenza virus M2, or a vector for mRNA production comprising a promoter operably linked to a DNA segment encoding influenza virus NS2.