The cellular protein TIAR mediates rapid initiation of West Nile virus genome RNA synthesis.

TIAR protein facilitates rapid initiation of West Nile virus genome RNA synthesis by binding cooperatively to the 3'(-) stem-loop RNA in infected cells.

• Why it matters: Understanding how WNV efficiently replicates its genome is crucial for developing antiviral strategies, as early transcription is initially inefficient but then accelerates exponentially.
• What they did: Researchers used colocalization assays, RNA binding tests, immunoprecipitation, and overexpression experiments in A549 cells to investigate TIAR's role, focusing on its interaction with WNV RNA and its effect on viral RNA ratios.
• The result: Overexpression of TIAR increased the intracellular ratio of viral plus-strand to minus-strand RNA in a dose-dependent manner, and multiple TIAR molecules cooperatively bind to the WNV 3'(-) stem-loop, supporting TIAR's role in promoting rapid genome RNA synthesis.