Inefficient splicing of segment 7 and 8 mRNAs is an inherent property of influenza virus A/Brevig Mission/1918/1 (H1N1) that causes elevated expression of NS1 protein.
Influenza A virus encodes two segments (7 and 8) that produce mRNAs that can be spliced. We have investigated if naturally occurring sequence polymorphisms in the influenza A virus family affects splicing of these viral mRNAs, as that could potentially alter the NS1/NS2- and/or M1/M2-protein ratios. We compared splicing efficiency of segment 7 and 8 mRNAs of A/Brevig Mission/1918/1 (H1N1) and A/Ne
