GNL2 plays a critical role in avian reovirus p17-mediated host cellular autophagy and promotes viral proliferation.

Avian reovirus (ARV) is a major pathogen causing viral arthritis, tenosynovitis, malabsorption syndrome, and immunosuppression in chickens, leading to severe economic losses in the global poultry industry. The nonstructural protein p17 is vital for ARV replication and modulates diverse host signaling pathways by interacting with multiple host factors. In our previous work, nucleolar GTP‑binding protein 2 (GNL2), a conserved nucleolar GTPase governing 60S ribosomal subunit maturation and nucleocytoplasmic transport, was screened as a potential binding partner of ARV p17 using yeast two‑hybrid assay. In the present study, the physical interaction between p17 and GNL2 was validated by coimmunoprecipitation (Co‑IP), glutathione S‑transferase (GST) pull‑down, and laser confocal microscopy. Mechanistically, the central region of p17 (amino acids 19-61) directly binds to the GTPase domain of GNL2. Notably, ARV infection or ectopic expression of p17 significantly upregulates GNL2 expression. Functional assays revealed that GNL2 overexpression markedly promotes ARV replication at both RNA and protein levels, whereas GNL2 knockdown remarkably restricts viral proliferation. Furthermore, GNL2 enhances p17‑mediated cellular autophagosome formation, thereby constructing a favorable intracellular milieu for efficient ARV propagation. Collectively, these findings demonstrate that GNL2 serves as a key host dependency factor hijacked by ARV p17 to remodel host cellular functions. This study provides new insights into the molecular pathogenesis of ARV and offers potential targets for developing antiviral strategies against ARV infection.