Yao Huan, Zhang Danru, Jin Haixia, Guo Yanjie, Liu Yan, Wang Shengnan, Li Tong, Yuan Shenli, Lu Gang, Sun Yingpu
Center for Reproductive Medicine, Henan Key Laboratory of Reproduction and Genetics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.
CUHK-SDU Joint Laboratory On Reproductive Genetics, School of Biomedical Sciences, The Chinese University of Hong Kong, Ma Liu Shui, Hong Kong.
BMC Biol. 2025 May 28;23(1):147. doi: 10.1186/s12915-025-02250-7.
Omics technologies are widely applied in assisted reproductive technology (ART), such as embryo selection, investigation of infertility causes, and mechanisms underlying reproductive cell development. While RNAomics has shown great potential in investigating the physiology and pathology in female reproductive system, its applications are still not fully developed. More studies on epitranscriptomic regulation mechanisms and novel sequencing methods are needed to advance the field.
Here, we developed a method named Cap to Tail sequencing application (C2T-APP) and simultaneously characterized the mG cap, poly(A) tail structure, and gene expression level for the intact RNA molecules in single cells. C2T-APP distinguished the N6, 2'-O-dimethyladenosine modification (mA) from N-methyladenosine (mA) modification with our published single-cell mA sequencing (scmA-seq) data. During oocyte maturation, we found a positive correlation of mG and mA with translation efficiency and finely dissected the step-wised maternal RNA de-capping and de-tailing of different types of genes. Strikingly, we uncovered a subtle structural mechanism regulating poly(A) tails in oocytes: maternal RNA translation is temporarily suppressed by removing the poly(A) tails without complete degradation, while the poly(A)-tail regulators themselves depend strictly on translation initiated after meiotic resumption. Furthermore, we profiled single-cell RNA-multi-omic features of human oocytes with different qualities during in vitro culture maturation (IVM). Defects of epi-transcriptome features, including mA, mA, mG, and poly(A) structure of maternal RNA in the oocytes with poor quality, were detected.
Our results provided a valuable tool for RNAomics research and data resources provided novel insights into human oocyte maturation, which is helpful for IVM and oocyte selection for ART.
组学技术在辅助生殖技术（ART）中广泛应用，如胚胎选择、不孕原因调查以及生殖细胞发育的潜在机制研究。虽然RNA组学在研究女性生殖系统的生理和病理方面已显示出巨大潜力，但其应用仍未得到充分发展。需要更多关于表观转录组调控机制和新型测序方法的研究来推动该领域的发展。
在此，我们开发了一种名为Cap to Tail测序应用（C2T-APP）的方法，并同时对单细胞中完整RNA分子的mG帽、聚腺苷酸（poly(A)）尾结构和基因表达水平进行了表征。C2T-APP利用我们已发表的单细胞m⁶A测序（scm⁶A-seq）数据，区分了N⁶,2'-O-二甲基腺苷修饰（m⁶A）和N-甲基腺苷（m⁶A）修饰。在卵母细胞成熟过程中，我们发现mG和m⁶A与翻译效率呈正相关，并精细剖析了不同类型基因逐步进行的母源RNA脱帽和去尾过程。令人惊讶的是，我们揭示了一种调控卵母细胞中聚腺苷酸尾的微妙结构机制：通过去除聚腺苷酸尾而不完全降解来暂时抑制母源RNA翻译，而聚腺苷酸尾调节因子本身则严格依赖减数分裂恢复后启动的翻译。此外，我们分析了体外培养成熟（IVM）过程中不同质量人类卵母细胞的单细胞RNA多组学特征。检测到质量较差的卵母细胞中母源RNA的表观转录组特征缺陷，包括m⁶A、m⁶A、mG和聚腺苷酸结构。
我们的结果为RNA组学研究提供了有价值的工具，所提供的数据资源为人类卵母细胞成熟提供了新见解，这有助于IVM和ART中的卵母细胞选择。
