Guanylate-binding protein 1 restricts avian coronavirus infectious bronchitis virus-infected HD11 cells

The Infectious Bronchitis Virus (IBV), a coronavirus, is a key avian pathogen that causes acute and highly infectious viral respiratory diseases. IBV is an enveloped, positive-sense RNA virus, and the host factors that restrict infection and replication of the virus remain poorly understood. Guanylate-binding protein 1 (GBP1), an interferon-gamma (IFN-g)-inducible guanosine triphosphatase (GTPase), is a major player in host immunity and provides defense against viral replication. However, the role of chicken GBP1 (chGBP1) in the IBV-life cycle is not well understood. Therefore, this study aimed to reveal the potential role of IFN-g-induced chGBP1 in mediating host anti-IBV infection responses. We identified the host restriction factor, chGBP1, in IBV-infected chicken macrophages HD11 cell lines. We showed that chGBP1 was upregulated by treatment with both IFN-g and IBV in HD11 cells. chGBP1 inhibited IBV repli-cation in a dose-dependent manner and enhanced IFN-g anti-IBV activity. Importantly, the GTPase domain of chGBP1 played a pivotal role in its anti-IBV activ-ity. Furthermore, chGBP1 interacts with IBV Nucleo-capsids protein to degrade IBV-N protein through the autophagy pathway. Taken together, our results dem-onstrate a critical role of chGBP1 in anti-IBV in mac-rophages HD11 cells.

Automated summary

This study reveals the critical role of chicken GBP1 (chGBP1) in combating Infectious Bronchitis Virus (IBV) infection by inhibiting viral replication and enhancing the anti-viral activity of IFN-g. chGBP1 interacts with IBV Nucleocapsid protein to degrade the IBV-N protein through the autophagy pathway.