Interferon-induced human MxA GTPase blocks nuclear import of Thogoto virusnucleocapsids

Interferon-induced human MxA protein belongs to the dynamin superfamily of large GTPases. It exhibits antiviral activity against a variety of RNA viru ses, including Thogoto virus, an influenza virus-like orthomyxovirus transm itted by ticks. Here, we report that MxA blocks the transport of Thogoto vi rus nucleocapsids into the nucleus, thereby preventing transcription of the viral genome. This interaction can be abolished by a mAb that neutralizes the antiviral activity of MxA. Our results reveal an antiviral mechanism wh ereby an interferon-induced protein traps the incoming virus and interferes with proper transport of the viral genome to its ultimate target compartme nt within the infected cell.