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11:48
Detection of Alternative Splicing During Epithelial-Mesenchymal Transition
Published on: October 9, 2014
Developmental consequences of alternative Bcl-x splicing during preimplantation embryo development
Alagammal Perumalsamy1, Roxanne Fernandes, Ingrid Lai
1Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, ON, Canada.
The FEBS Journal
|February 9, 2010
Summary
Elevated cell death in early human embryos, linked to Bcl-xS splicing, compromises pregnancy rates. In vitro culture conditions can exacerbate this, impacting embryo development.
Area of Science:
- Reproductive Biology
- Developmental Biology
- Molecular Biology
Background:
- Elevated cell death in human preimplantation embryos reduces pregnancy success in assisted reproductive technology.
- Understanding molecular pathways regulating embryo cell death is crucial for improving fertility treatments.
Purpose of the Study:
- To investigate molecular pathways governing cell death in human blastocysts.
- To characterize the role of Bcl-x splicing in embryo development and cell death.
Main Methods:
- Gene expression analysis in human and mouse blastocysts.
- Antisense experiments to alter Bcl-x isoform ratios in mouse embryos.
- Assessment of reactive oxygen species and mitochondrial DNA content.
Main Results:
- A positive correlation was found between cell death index and Bcl-x transcript expression.
- Cell death activation in human blastocysts involved splicing changes favoring Bcl-xS.
- Upregulation of Bcl-xS in mouse embryos compromised development and increased reactive oxygen species.
- Culture in HTF medium or excess glucose altered Bcl-x splicing, impairing embryo development.
Conclusions:
- Inappropriate in vitro culture conditions can dysregulate Bcl-x isoform expression.
- Altered Bcl-x splicing, favoring Bcl-xS, contributes to compromised preimplantation embryo development.
- Targeting Bcl-x splicing may offer strategies to improve embryo viability in assisted reproduction.
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