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Isolation and Characterization of Mouse Antral Oocytes Based on Nucleolar Chromatin Organization
Published on: January 7, 2016
Developmental arrest and mouse antral not-surrounded nucleolus oocytes
Manuela Monti1, Mario Zanoni, Alberto Calligaro
1Scientific Department, Research Center for Regenerative Medicine, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy. m.monti@smatteo.pv.it
Biology of Reproduction
|November 9, 2012
Summary
Oocyte development is hindered in mammals due to a lack of cytoplasmic lattices, impacting embryo progression. Reduced MATER expression and ribosomal proteins in not-surrounded nucleolus (NSN) oocytes cause this developmental arrest.
Area of Science:
- Reproductive Biology
- Developmental Biology
- Oocyte Biology
Background:
- Antral oocytes comprise two populations: surrounded nucleolus (SN) and not-surrounded nucleolus (NSN).
- SN oocytes develop to blastocyst stage, while NSN oocytes arrest at the two-cell stage.
- The molecular basis for NSN oocyte arrest remains unclear.
Purpose of the Study:
- To investigate the molecular mechanisms underlying NSN oocyte developmental arrest.
- To determine the role of MATER and cytoplasmic lattices in oocyte development.
Main Methods:
- Transcriptomic, proteomic, and morphological profiling of antral oocytes.
- Isolation and analysis of oocytes from Mater(tm/tm) mice.
Main Results:
- NSN oocyte arrest is linked to absent cytoplasmic lattices and reduced expression of MATER and ribosomal proteins.
- MATER is essential for cytoplasmic lattice formation.
- Oocytes from Mater(tm/tm) mice predominantly exhibit the NSN phenotype (84%).
Conclusions:
- This study provides the first molecular evidence explaining the inability of NSN-derived embryos to progress beyond the two-cell stage.
- Findings may offer insights into naturally occurring preimplantation embryo demise in mammals.
- MATER deficiency disrupts cytoplasmic lattice formation, leading to oocyte developmental arrest.
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