Do Dang Vinh, Strauss Bernhard, Cukuroglu Engin, Macaulay Iain, Wee Keng Boon, Hu Tim Xiaoming, Igor Ruiz De Los Mozos, Lee Caroline, Harrison Andrew, Butler Richard, Dietmann Sabine, Jernej Ule, Marioni John, Smith Christopher W J, Göke Jonathan, Surani M Azim
1Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QN UK.
2Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge, CB2 3DY UK.
Cell Discov. 2018 Jun 19;4:33. doi: 10.1038/s41421-018-0032-3. eCollection 2018.
The RNA-binding protein SRSF3 (also known as SRp20) has critical roles in the regulation of pre-mRNA splicing. Zygotic knockout of results in embryo arrest at the blastocyst stage. However, SRSF3 is also present in oocytes, suggesting that it might be critical as a maternally inherited factor. Here we identify SRSF3 as an essential regulator of alternative splicing and of transposable elements to maintain transcriptome integrity in mouse oocyte. Using 3D time-lapse confocal live imaging, we show that conditional deletion of in fully grown germinal vesicle oocytes substantially compromises the capacity of germinal vesicle breakdown (GVBD), and consequently entry into meiosis. By combining single cell RNA-seq, and oocyte micromanipulation with steric blocking antisense oligonucleotides and RNAse-H inducing gapmers, we found that the GVBD defect in mutant oocytes is due to both aberrant alternative splicing and derepression of B2 SINE transposable elements. Together, our study highlights how control of transcriptional identity of the maternal transcriptome by the RNA-binding protein SRSF3 is essential to the development of fertilized-competent oocytes.
RNA 结合蛋白 SRSF3（也称为 SRp20）在 pre-mRNA 剪接调控中起关键作用。合子敲除 SRSF3 会导致胚胎在囊胚阶段停滞。然而，SRSF3 也存在于卵母细胞中，这表明它作为母系遗传因子可能至关重要。在这里，我们确定 SRSF3 是维持小鼠卵母细胞转录组完整性的可变剪接和转座元件的重要调节因子。使用 3D 延时共聚焦实时成像，我们表明在完全生长的生发泡卵母细胞中条件性删除 SRSF3 会严重损害生发泡破裂（GVBD）的能力，从而导致进入减数分裂。通过将单细胞 RNA 测序以及卵母细胞显微操作与空间位阻反义寡核苷酸和 RNA 酶 H 诱导性 Gapmer 相结合，我们发现突变卵母细胞中的 GVBD 缺陷是由于异常的可变剪接和 B2 SINE 转座元件的去抑制所致。总之，我们的研究强调了 RNA 结合蛋白 SRSF3 对母系转录组转录身份的控制对于有受精能力的卵母细胞发育至关重要。
