PARP12 regulates mouse oocyte meiotic maturation

Area of Science:

• Cell Biology
• Molecular Biology
• Reproductive Biology

Background:

• Poly(ADP-ribosyl)ation (PARylation) is a critical post-translational modification involved in numerous cellular processes.
• While PARylation's role in oocyte maturation is recognized, the specific contribution of Mono(ADP-ribosyl)ation (MARylation) remains largely unexplored.

Purpose of the Study:

• To investigate the role of Parp12, a MARylating enzyme, in mouse oocyte meiotic maturation.
• To elucidate the molecular mechanisms by which Parp12 influences oocyte development.

Main Methods:

• Quantitative analysis of Parp12 expression and localization during oocyte maturation.
• Functional studies involving Parp12 depletion (knockdown) in mouse oocytes.
• Assessment of spindle organization, chromosome alignment, and aneuploidy.
• Analysis of spindle assembly checkpoint activation and F-actin dynamics.
• Transcriptomic analysis to evaluate global gene expression changes.

Main Results:

• Parp12 is highly expressed throughout oocyte maturation and exhibits dynamic localization, including aggregation near spindle poles.
• Parp12 depletion leads to abnormal spindle organization, chromosome misalignment, and increased aneuploidy.
• Parp12 knockdown activates the spindle assembly checkpoint and reduces F-actin levels.
• Transcriptomic analysis reveals that Parp12 depletion disrupts overall transcriptome homeostasis.

Conclusions:

• Maternally expressed Parp12 is essential for maintaining genomic stability and proper progression of mouse oocyte meiosis.
• Parp12 plays a crucial role in regulating spindle organization, chromosome segregation, and potentially asymmetric division during oocyte maturation.