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Updated: Jul 19, 2026
07:21
Generation of Naïve Blastoderm Explants from Zebrafish Embryos
Published on: July 30, 2021
Nuclear receptor NR5A2 is required for proper primitive streak morphogenesis.
Cassandre Labelle-Dumais1, Mariève Jacob-Wagner, Jean-Francois Paré
1Division of Experimental Medicine, Department of Obstetrics and Gynecology, McGill University, RVH, Montreal, Canada.
Summary
Nuclear Receptor NR5A2 is crucial for early mouse development, regulating primitive streak formation and mesoderm generation. Its absence causes embryonic lethality due to impaired gastrulation.
Area of Science:
- Developmental Biology
- Molecular Biology
- Genetics
Background:
- NR5A2 (also known as LRH-1/FTF) is an orphan nuclear receptor vital for adult cholesterol metabolism and steroidogenesis.
- NR5A2 is expressed early in mouse embryogenesis, suggesting a role in embryonic development.
Purpose of the Study:
- To investigate the embryonic phenotype and developmental role of NR5A2 loss of function.
- To understand NR5A2's contribution to gastrulation and mesoderm formation.
Main Methods:
- Morphological and marker gene analyses of NR5A2 knockout (NR5A2-/-) mouse embryos.
- Aggregation experiments using NR5A2 mutant epiblast cells and wild-type tetraploid cells.
Main Results:
- NR5A2-/- embryos exhibit growth retardation, epiblast disorganization, and impaired primitive streak formation.
- Absence of NR5A2 prevents embryonic and extraembryonic mesoderm generation, despite initial anterior-posterior axis specification.
- Visceral endoderm shows reduced HNF4 and GATA4 expression; aggregation experiments show NR5A2 mutant cells can gastrulate in a wild-type environment.
Conclusions:
- NR5A2 is essential for proper primitive streak morphogenesis and mesoderm development during early embryogenesis.
- The study identifies a novel role for NR5A2 in extraembryonic tissues, critical for embryonic development.
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