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Updated: Jul 25, 2025
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Affinity Purification of Influenza Virus Ribonucleoprotein Complexes from the Chromatin of Infected Cells
Published on: June 3, 2012
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Local changes in viral RNA sequence drive global changes in influenza nucleoprotein binding
Valerie Le Sage1, Jack P Kanarek1, Seema S Lakdawala2
1Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.
Journal of Medical Virology
|June 30, 2023
Summary
Influenza A virus RNA binding by nucleoprotein (NP) is not solely determined by the primary sequence. Nucleotide changes reveal that NP binding is influenced by a complex network across multiple viral RNA segments.
Area of Science:
- Virology
- Molecular Biology
- Genomics
Background:
- Influenza A virus (IAV) genome comprises eight negative-sense RNA segments coated by viral nucleoprotein (NP).
- Previous models assumed uniform NP binding to viral genomic RNA (vRNA), but recent studies show preferential binding to specific regions.
- Distinct NP-binding profiles exist even among highly similar IAV strains, leaving the specificity mechanism unclear.
Purpose of the Study:
- To investigate whether the primary nucleotide sequence of vRNA influences NP binding specificity.
- To understand the regulatory mechanisms governing NP deposition on the IAV genome.
Main Methods:
- Introduction of specific nucleotide changes into vRNA segments.
- Genome-wide analysis of NP binding profiles before and after mutagenesis.
- Assessment of local and distal effects of nucleotide alterations on NP binding.
Main Results:
- Nucleotide alterations in vRNA significantly affect NP binding, causing loss or appearance of NP-binding sites.
- Mutations impact NP binding both locally at the mutation site and at distant, unmodified vRNA regions.
- Evidence suggests NP binding is not solely dependent on the immediate nucleotide sequence.
Conclusions:
- IAV nucleoprotein (NP) binding to viral RNA (vRNA) is regulated by a complex interplay, not just the primary sequence.
- A network involving multiple viral RNA segments likely governs NP deposition onto the genome.
- These findings revise the understanding of viral RNA-genome organization and regulation in influenza A viruses.
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