The non-structural protein NS1 of influenza A virus exhibits two modes of RNA-binding activity. One is sequence-specific binding to minus-sense virus RNA with either a 5′- or 3′-terminal common sequence as reported previously. The other was identified as binding to dsRNA and this activity did not show sequence specificity. The affinity of binding to dsRNA was much higher than that to ssRNA. A short miniature virion RNA forming a panhandle structure by pairing between the 5′- and 3′-terminal common sequences bound NS1 with higher affinity and stability than did a dsRNA of similar sequence and length.
Alonso-CaplenF. V.,
NemeroffM. E.,
QiuY.,
KrugR. M.1992; Nucleocytoplasmic transport: the influenza virus NS1 protein regulates the transport of spliced NS2 mRNA and its precursor NS1 mRNA. Genes and Development 6:255–267
HatadaE.,
HasegawaM.,
ShimizuK.,
HatanakaM.,
FukudaR.1990; Analysis of influenza A virus temperature-sensitive mutants with mutations in RNA segment 8. Journal of General Virology 71:1283–1292
HatadaE.,
TakizawaT.,
FukudaR.1992; Specific binding of influenza A virus NS1 protein to the virus minus-sense RNA in vitro
. Journal of General Virology 13:17–25
HsuM. T.,
ParvinJ. D.,
GuptaS.,
KrystalM.,
PaleseP.1987; Genomic RNAs of influenza viruses are held in a circular conformation in virions and in infected cells by a terminal panhandle. Proceedings of the National Academy of Sciences, U.S.A. 84:8140–8144
InglisS. C.,
GethingM.-J.,
BrownC. M.1980; Relationship between the messenger RNAs transcribed from two overlapping genes of influenza virus. Nucleic Acids Research 8:3575–3589
LambR. A.,
LaiC.-J.1980; Sequence of interrupted and uninterrupted mRNAs and cloned DNA coding for the two overlapping nonstructural proteins of influenza virus. Cell21475–485