Related Experiment Video
Updated: Aug 5, 2025
Microinjection of Medaka Embryos for use as a Model Genetic Organism
Published on: December 22, 2010
Mep50 is essential for embryonic development in medaka fish
Qiting Yao1, Shi Duan1, Qing Yang1
1Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan 430079, China.
Abstract:
Mep50 as a partner promotes the activity and substrate affinity of Prmt5. Prmt5 and Mep50 function together in multiple bioprocesses of the cells. Both Prmt5 and Mep50 are necessary for maintenance of the stem cells and are indispensable in the embryogenesis in the mammals. However, the role of Mep50 is rarely studied in fish. This study was to investigate the role of Mep50 in embryonic development of medaka. Medaka mep50 was mutated by genomic editing with CRISPR-Cas9 technology. Two mutants with a deletion of 22 and 46 bp separately in mep50 caused premature stopping of translation. The homozygotes of these mutant fish were obtained by self-crossing of the heterozygotes. These homozygotic mutants could reproduce embryos but the offspring were not viable. The apoptotic cells were significantly more in the mutant embryos than that in the wild type indicated by TUNEL assay. Quantitative RT-PCR showed that the expression of oct4 and sox2 were significantly decreased, but p53 was increased in the mutant embryos. These results suggest that disruption of mep50 severely interferes with embryogenesis and mep50 is necessary for embryonic development by maintaining stem cells and repression of apoptosis in medaka.
Insights
The study found that Mep50 is crucial for medaka embryonic development. Disrupting Mep50 leads to non-viable offspring, increased apoptosis, and altered stem cell gene expression, highlighting Mep50
Area of Science:
- Developmental Biology
- Genetics
- Molecular Biology
Background:
- Mep50 partners with Prmt5, enhancing its activity and substrate affinity.
- Both Prmt5 and Mep50 are essential for stem cell maintenance and mammalian embryogenesis.
- The specific role of Mep50 in fish embryonic development remains largely unexplored.
Purpose of the Study:
- To investigate the function of Mep50 during embryonic development in medaka.
- To elucidate the consequences of Mep50 disruption on medaka embryogenesis.
Main Methods:
- Medaka mep50 gene was mutated using CRISPR-Cas9 genome editing technology.
- Generated homozygous mutants with deletions in mep50, leading to premature translation termination.
- Assessed embryonic viability, apoptosis levels (TUNEL assay), and gene expression (Quantitative RT-PCR for oct4, sox2, p53).
Main Results:
- Homozygous mep50 mutants produced non-viable offspring.
- Mutant embryos exhibited significantly increased apoptosis compared to wild-type embryos.
- Downregulation of stem cell markers (oct4, sox2) and upregulation of p53 were observed in mutant embryos.
Conclusions:
- Mep50 is essential for successful medaka embryonic development.
- Disruption of Mep50 severely impairs embryogenesis, likely by affecting stem cell maintenance and apoptosis regulation.
- Mep50 plays a critical role in maintaining stem cells and repressing apoptosis during medaka development.
