FIG 7.

Venus-NS and deleted NS segments of Venus-H5N1-related reassortants. Viruses were passaged five times in MDCK cells, and the vRNAs from the fifth passages were extracted by using a QIAamp viral RNA minikit (Qiagen). The respective NS segments were then amplified by PCR with NS-specific primers and run on an agarose gel. Lane 1, WT+MA-NS; lane 2, WT+MA-M; lane 3, WT+MA-NA; lane 4, WT+MA-PA; lane 5, WT+MA-PB1; lane 6, WT+MA-PB2; lane 7, WT+MA-(PB2+PA); lane 8, WT-Venus-H5N1; lane 9, rgMA-Venus-H5N1; lane 10, PR8; lane 11, 1-kb DNA marker.