What allows the viral genome RNA to spread to other cells ?
Segment 6 encodes an RNA polymerase ( PA ) ; an alternate form of this polymerase can sometimes be made with a change to the reading frame Segment 7 encodes another RNA polymerase ( PB1 ) and the PB1 - F2 protein , which induces cell death , by using different reading frames from the same RNA segment Segment 8 encodes a third RNA polymerase ( PB2 ) .