Furthermore, after 36 h of infection with two shRNA lentivirus targeting SETDB1 respectively, the cell morphology was changed, which is similar to that after deletion of TRIM28 (Additional file 4: Fig. S4A), and deletion of SETDB1 also decreased the level of C-circle in U2OS cells (Additional file 4: Fig. S4B). The gene discussed is TRIM28; the disease is infection.