Discovery of Oogenesis Biomarkers from Mouse Oocytes Using a Single-Cell Proteomics Approach

We established an efficient and simplified single-cell proteomics (ES-SCP) workflow to realize proteomics profiling at the single-oocyte level. With the ES-SCP workflow, we constructed a deep coverage proteome library during oocyte maturation, which contained more than 6000 protein groups, and identified and quantified more than 4000 protein groups from a pool of only 15 oocytes at germinal vesicle (GV), GV breakdown (GVBD), and metaphase II (MII) stages. More than 1500 protein groups can be identified from single oocytes. We found that marker proteins including maternal factors and mRNA regulators, such as ZAR1, TLE6, and BTG4, showed significant variations in abundance during oocyte maturation, and it was discovered that maternal mRNA degradation was indispensable during oocyte maturation. Proteomics analysis from single oocytes revealed that changes in antioxidant factors, maternal factors, mRNA stabilization, and energy metabolism were the factors that affect the oocyte quality during ovary aging. Our data laid the foundation for future innovations in assisted reproduction.

Automated summary

We developed an efficient and simplified workflow for single-cell proteomics analysis, allowing us to profile the proteome at the individual oocyte level. By using this workflow, we constructed a comprehensive proteome library during oocyte maturation, identifying and quantifying more than 4000 protein groups from only 15 oocytes. Our analysis revealed significant variations in abundance for marker proteins and highlighted the importance of maternal mRNA degradation during oocyte maturation. Furthermore, our findings shed light on the factors affecting oocyte quality during ovary aging, including changes in antioxidant factors, maternal factors, mRNA stabilization, and energy metabolism. This study lays the foundation for future advancements in assisted reproduction techniques.