The 5'-end segment-specific noncoding region of influenza A virus regulates both competitive multi-segment RNA transcription and selective genome packaging during infection.
Influenza A virus's 5'-end noncoding regions regulate both competitive RNA transcription and selective genome packaging - a dual regulatory role that's crucial for viral replication and infection.
This study investigated the role of the 5'-end segment-specific noncoding regions (ssNCRs) of influenza A virus (IAV) in regulating viral RNA transcription and genome packaging. The researchers found that truncation of the 5'-end H1-ssNCR reduced HA mRNA levels in a template-competitive manner and impaired HA vRNA incorporation into progeny virions. An adaptive mutation upstream of the truncation site restored HA mRNA expression and HA vRNA packaging, rescuing viral replication. The findings reveal a previously unknown dual regulatory function of the 5'-end ssNCRs in modulating multi-segmental RNA transcription and selective genome packaging during IAV infection. This provides new insights into the complex mechanisms governing IAV replication and could inform the development of antiviral strategies.