Autophagy regulates early embryonic development in mice via affecting H3K4me3 modification

Hu Jing; Zhu Ling; Xie Juan; Kong Deying; Liu Doudou

doi:10.12307/2026.022

Abstract：BACKGROUND:Autophagy,as a key regulatory mechanism of cell development,plays an important role in different stages of embryonic development.The mechanism of how autophagy regulates embryonic development through histone modifications is currently unclear. OBJECTIVE:To investigate the effect of autophagy on trimethylation of lysine 4 on histone H3(H3K4me3)modification in embryos and its effect on embryonic development. METHODS:Mouse fertilized eggs were divided into control and autophagy inhibitor-treated groups(chloroquine phosphate-treated group and 3-methyladenine-treated group),and cultured in vitro to different periods of time,and were then classified as early 2-cell embryos,middle 2-cell embryos,late 2-cell embryos,4-cell embryos,8-cell embryos,morula stage,and blastocyst stage.Levels of reactive oxygen species,autophagy marker proteins LC3B and P62,DNA loss marker γH2AX,and H3K4me3 were analyzed by immunofluorescence assay in late 2-cell embryos of each group.Changes in H3K4me3 modification in late 2-cell embryos of each group were detected by CUT&Tag. RESULTS AND CONCLUSION:(1)Autophagy inhibition caused embryo development arrest.(2)There was no significant difference in reactive oxygen species and γH2AX between the autophagy inhibitor-treated groups and control group.(3)H3K4me3 levels were significantly elevated in the autophagy inhibitor-treated group compared with the control group.(4)CUT&Tag results showed a significantly increased H3K4me3 peaks on the proximal promoter region of the genes after autophagy inhibition and an increase of H3K4me3-specific modification genes.These findings suggest that autophagy may affect embryonic development by regulating the level of H3K4me3 modification.