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

G-四链体（G-quadruplex，G4）结构的功能及其对卵母细胞与早期胚胎发育的影响目前仍不明确。本研究发现，G-四链体解旋酶DHX36对卵母细胞生长及母源-合子转换（MZT）至关重要。对DHX36进行条件性基因敲除会导致小鼠卵母细胞内DNA G4聚集，降低染色质可及性并抑制RNA转录，最终破坏卵母细胞生长及MZT过程中的转录组稳态。实验设计概述：我们对野生型（WT）与DHX36条件性基因敲除（CKO）雌性小鼠的样本开展Smart-seq2测序，样本包括生长中卵母细胞（2周龄）、完全成熟卵母细胞（3周龄及4周龄）、第二次减数分裂中期卵母细胞（3周龄）以及合子（3周龄）。