SALL4 ensures oocytes maturation by modulating DNA methylation and histone modifications (RRBS)

Splat-like 4 (Sall4) plays important roles in maintaining pluripotency of embryonic stem cells and in various developmental processes. Here, we find that the SALL4 null oocytes fail to undergo maturation to form fully-grown oocytes (FGOs) and subsequent meiosis resumption. We further discover that the loss of maternal SALL4 causes failure in establishment of DNA methylation. Moreover, we demonstrate that SALL4 modulates H3K4me3 and H3K27me3 modifications by regulating the expression of Kdm5b, Kdm6a and Kdm6b. Taken together, SALL4 plays pivotal roles in oocyte epigenetic maturation. Overall design: In this study, we have 19 RNA-seq data and 18 RRBS data. As for RNA-seq, secondary follicle (SF) stage WT oocyte group have 2 replicates, and SF stage oocyte group have 3 replicates. Early antral follicle (EAF) stage Sall4 KO or WT oocyte group both have 3 replicates. In the microinjection experiments, the control group have 5 replicates, and the experimental group have 3 replicates. As for RRBS, SF WT group have 7 replicates, and SF Sall4 KO group have 5 replicates. EAF WT group have 4 replicates, and EAF Sall4 KO group have 2 replicates.