To determine downstream genes and pathways that are affected by the loss of endothelial Atf3 during lung regeneration, we isolated pulmonary ECs from Atf3EC-WT and Atf3EC-KO mice using FACS for tdTomato+ cells at 14 days post influenza infection and performed population RNA sequencing to determine gene expression differences in Atf3-KO ECs during this key phase of injury repair (Figure 4A). Here, ATF3 is linked to influenza.