To confirm that low oxygen level positively regulates Angpt4 expression, Angpt4Cre/+; Rosa26mT/mG mice were exposed to low oxygen atmosphere (Figure 2E–G) and retinal ischemia (OIR model, Figure 2—figure supplement 1A–E) that both increased the number of Angpt4+ astrocytes. This evidence concerns the gene ANGPT4 and retinal ischemia.