RIKEN Omics Science Center, Yokohama, Kanagawa, Japan.
PLoS One. 2012;7(9):e44542. doi: 10.1371/journal.pone.0044542. Epub 2012 Sep 12.
The recent discovery of a significant amount of RNA in spermatozoa contradicted the previously held belief that paternal contribution was limited to one copy of the genome. Furthermore, detection of RNA in sperm raised the intriguing question of its possible role in embryonic development. The possibility that RNAs may serve as epigenetic determinants was supported by experiments showing inheritance of epigenetic traits in mice mediated by RNA. We used high-throughput, large-scale sequencing technology to analyze sperm RNA. The RNA sequences generated were diverse in terms of length and included mRNAs, rRNAs, piRNAs, and miRNAs. We studied two small noncoding RNAs enriched in mature sperm, designated sperm RNAs (spR) -12 and -13. They are both encoded in a piRNA locus on chromosome 17, but neither their length (20-21 nt), nor their sequences correspond to known piRNAs or miRNAs. They are resistant to periodate-oxidation-mediated reaction, implying that they undergo terminal post-transcriptional modification. Both were detected in sperm and ovulated unfertilized oocytes, present in one-cell embryos and maintained in preimplantation stages, but not at later differentiation stages. These findings offer a new perspective regarding a possibly important role for gamete-specific small RNAs in early embryogenesis.
最近在精子中发现了大量的 RNA，这与之前认为父系贡献仅限于基因组的一份拷贝的观点相矛盾。此外，在精子中检测到 RNA 引发了一个有趣的问题，即它在胚胎发育中可能发挥作用。实验表明，RNA 可以作为表观遗传决定因素，这支持了 RNA 可能在介导小鼠中表观遗传特征遗传中的作用的观点。我们使用高通量、大规模测序技术来分析精子 RNA。生成的 RNA 序列在长度上具有多样性，包括 mRNA、rRNA、piRNA 和 miRNA。我们研究了两种在成熟精子中富集的小非编码 RNA，分别命名为精子 RNA (spR) -12 和 -13。它们都编码在 17 号染色体上的一个 piRNA 基因座上，但它们的长度（20-21nt）和序列都不对应已知的 piRNA 或 miRNA。它们对过碘酸钠介导的反应具有抗性，这意味着它们经历了末端转录后修饰。这两种 RNA 都在精子和排出的未受精卵母细胞中被检测到，存在于单细胞胚胎中，并在植入前阶段维持，但不在后期分化阶段存在。这些发现为配子特异性小 RNA 在早期胚胎发生中可能发挥重要作用提供了新的视角。
