#326 : Multi-Omics Analysis Reveals Translational Landscapes and Regulations in Mouse and Human Oocyte Aging
Jiana Huang, Haitao Zeng, Xiaoyan Liang, Chuanchuan Zhou- General Medicine
Background and Aims: Abnormal resumption of meiosis and decreased oocyte quality are hallmarks of maternal aging and ultimately lead to infertility. Transcriptional silencing makes translational control an urgent task during meiosis resumption in maternal aging. However, insights into aging-related translational characteristics and underlying mechanisms are limited.
Method: Here, using multi-omics analysis of oocytes, including single-cell proteomics, ultrasensitive translatomics and transcriptomics, we profiled the multi-omics landscapes of mouse and human oocyte aging. The role and mechanisms underlying oocyte aging were explored and verified using immunofluorescence staining, electroporation, RNA immunoprecipitation (RIP) sequencing, quantitative PCR (qPCR), methylated RIP, and dual-luciferase reporter assay etc.
Results: We found that translatomics during aging was related to changes in the proteome and revealed decreased translational efficiency with aging phenotypes in mouse oocytes. Notably, the translational efficiency decrease was associated with the N6-methyladenosine (m6A) modification of transcripts. We clarified that the expression of the m6A reader YTH N6-methyladenosine RNA-binding protein 3 (YTHDF3) was significantly decreased in aged oocytes and inhibited oocyte meiotic maturation. YTHDF3 intervention perturbed the translatome of oocytes and suppressed the translational efficiency. We further identified Hells as an aging-associated maternal factor whose translation was suppressed during oocyte aging in a YTHDF3-dependent manner. Moreover, we profiled the translational landscape in human oocyte aging, and observed the same translational changes of DNA methylation regulatory enzymes and different regulation of histone modifications between human and mice oocytes aging. Translation efficiency was not changed in human oocytes aging. Due to translational silence of YTHDF3 in human oocytes, translation activity was not associated with m6A modification, but was related to alternative splicing factors, such as SRSF6.
Conclusion: Together, our findings profiled the specific translational landscapes during oocyte aging in mice and human and uncovered non-conservative regulators on translation control in meiosis resumption and maternal aging.