HDAC6 and infection: In the later phase of infection, PCV2 appears to induce the formation of autophagic flux, and simultaneously catalyzes the K48-linked poly-ubiquitination of cGAS at K389 and activates the deacetylase activity of histone deacetylase 6 (HDAC6), which recruits K48-ubiquitinated-cGAS through its ubiquitin-binding domain and transports ubiquitinated-cGAS from the cytosol to autolysosome depending on its deacetylase activity, ultimately resulting in cGAS degradation in PCV2-infected cells.