DHX36-mediated G-quadruplexes unwinding is essential for oocyte and early embryo development in mice

The role of G-quadruplex (G4) structures and their effects on oocyte and early embryo development remain unclear. We discovered that the G4 helicase DHX36 is essential for oocyte growth and the maternal-to-zygotic transition (MZT). Conditional knockout of DHX36 resulted in DNA G4 accumulation in mouse oocytes, reducing chromatin accessibility, and inhibiting RNA transcription, ultimately disrupting transcriptome homeostasis during oocyte growth and MZT. Overall design: We performed Smart-seq2 on samples from wild-type (WT) and DHX36 conditional knockout (CKO) female mice, including growing oocytes (2-week-old), fully-grown oocytes (3-week-old and 4-week-old), metaphase II oocytes (3-week-old), and zygotes (3-week-old).