PDF(Pubmed)
Abstract：
Maternal inactivation of genes encoding components of the subcortical maternal complex (SCMC) and its associated member, PADI6, generally results in early embryo lethality. In humans, SCMC gene variants were found in the healthy mothers of children affected by multilocus imprinting disturbances (MLID). However, how the SCMC controls the DNA methylation required to regulate imprinting remains poorly defined. We generated a mouse line carrying a Padi6 missense variant that was identified in a family with Beckwith-Wiedemann syndrome and MLID. If homozygous in female mice, this variant resulted in interruption of embryo development at the two-cell stage. Single-cell multiomic analyses demonstrated defective maturation of Padi6 mutant oocytes and incomplete DNA demethylation, down-regulation of zygotic genome activation (ZGA) genes, up-regulation of maternal decay genes, and developmental delay in two-cell embryos developing from Padi6 mutant oocytes but little effect on genomic imprinting. Western blotting and immunofluorescence analyses showed reduced levels of UHRF1 in oocytes and abnormal localization of DNMT1 and UHRF1 in both oocytes and zygotes. Treatment with 5-azacytidine reverted DNA hypermethylation but did not rescue the developmental arrest of mutant embryos. Taken together, this study demonstrates that PADI6 controls both nuclear and cytoplasmic oocyte processes that are necessary for preimplantation epigenetic reprogramming and ZGA.
摘要：
编码皮质下母体复合体（SCMC）及其相关成员成分的基因的母体失活，PADI6通常导致早期胚胎致死。在人类中,在受多基因座印记障碍（MLID）影响的儿童的健康母亲中发现了SCMC基因变异。然而,SCMC如何控制调节印迹所需的DNA甲基化仍不清楚。我们产生了一个携带Padi6错义变体的小鼠品系，该变体在一个患有Beckwith-Wiedemann综合征和MLID的家庭中被鉴定。如果雌性小鼠是纯合的，这种变异导致胚胎发育在两细胞阶段中断.单细胞多组分析显示Padi6突变卵母细胞的成熟缺陷和不完全的DNA去甲基化，合子基因组激活（ZGA）基因的下调，母体衰变基因的上调，从Padi6突变卵母细胞发育而来的两细胞胚胎的发育延迟，但对基因组印迹的影响很小。Western印迹和免疫荧光分析显示，卵母细胞中UHRF1的水平降低，卵母细胞和受精卵中DNMT1和UHRF1的异常定位。用5-氮杂胞苷处理恢复了DNA超甲基化，但不能挽救突变胚胎的发育停滞。一起来看,这项研究表明，PADI6控制着床前表观遗传重编程和ZGA所必需的核和细胞质卵母细胞过程。
