Lu, C.-Y.; Lai, P.-Y.; Huang, J.-M.; Chang, L.-Y.; Yen, T.-Y.; Tarn, W.-Y.; Huang, L.-M.

Respiratory syncytial virus (RSV) is a major cause of severe respiratory infections, yet effective treatments are lacking. We found that the molecular chaperon DNAJB6/MRJ plays an essential role in RSV replication. Depletion of the long isoform of MRJ (MRJ-L) suppresses RSV replication. Transcriptomic analysis revealed that MRJ-L depletion downregulates Wnt signaling pathways. A pharmacological inhibitor of Wnt signaling suppressed RSV propagation and unexpectedly reduced MRJ-L expression, suggesting a positive regulatory loop between Wnt signaling and MRJ-L expression. Notably, simultaneous inhibition of Wnt signaling and MRJ-L additively suppressed RSV replication, suggesting that the Wnt-MRJ-L axis may serve as a new therapeutic target. This study provides insights into host-RSV interactions and potential antiviral strategies.