SUMO2 and infection: To investigate whether the host SUMO system is impaired during SARS-CoV-2 infection, we examined the intracellular distribution of SUMO1 and SUMO2/3 in A549-hACE2 cells (a human non-small cell lung cancer cell line engineered to express human ACE2) with infection of the original strain of SARS-CoV-2 (SH01).