ULK1 and hydrops fetalis: To validate HF-induced autophagy through ULK1, the highly selective inhibitor SBI-0206965 was used to reduce HF-induced autophagy, indicating that HF regulates autophagy, at least partially, through ULK1 signaling (Figure 1d).12 Notably, not only the nutrient-sensing mTORC1, but also AMPK regulates phosphorylation of ULK1 at different sites for autophagic modulation.17, 18 In this regard, we further investigated AMPK-mediated phosphorylation at Ser317/Ser777 of ULK1 upon HF treatment under nutrient-poor condition.