The translational oscillation in oocyte and early embryo development

Area of Science:

• Molecular and Cellular Biology
• Developmental Biology
• Genetics and Genomics

Background:

• Transcription is silenced in oocytes and early embryos, making translation critical for development.
• Understanding translational control is key to deciphering early developmental processes.
• The oocyte-to-embryo transition involves complex gene expression regulation.

Purpose of the Study:

• To investigate genome-wide translational changes during oocyte meiosis and the first two embryonic mitoses.
• To elucidate the regulatory mechanisms governing translation during early development.
• To uncover the role of translational reprogramming in oocyte and embryo developmental competence.

Main Methods:

• Genome-wide translatome analysis was performed on oocytes and early embryos.
• Analysis focused on translational initiation and elongation factors.
• Investigated the involvement of the mTORC1/4E-BP/eEF2 axis in translational regulation.

Main Results:

• Significant and uniform activation of translational initiation and elongation axes during M-phases was observed.
• Despite decreased global protein synthesis, translation activity showed uniform fluctuations via the mTORC1/4E-BP/eEF2 pathway.
• A dynamic, oscillatory pattern of translational reprogramming was identified, impacting mRNA-specific translation.

Conclusions:

• Temporal translation regulation is dynamically controlled and oscillatory during early development.
• These findings provide new insights into gene expression regulation from oocyte meiosis to embryonic genome activation.
• This study lays the groundwork for comprehensive analysis of translation-related networks in early development.