Extensive apoptosis and abnormal morphogenesis in pro-caspase-3 transgenic zebrafish during development

Area of Science:

• Developmental Biology
• Molecular Biology
• Genetics

Background:

• Caspase-3 is crucial for apoptosis (programmed cell death) in vertebrates.
• Its specific role in embryonic development and morphogenesis is not fully understood.

Purpose of the Study:

• To investigate the function of caspase-3 in vertebrate development and stress tolerance using transgenic zebrafish.
• To determine the impact of enhanced caspase-3 activity on embryonic morphogenesis.

Main Methods:

• Generation of transgenic zebrafish overexpressing full-length pro-caspase-3.
• Analysis of morphological abnormalities and apoptosis levels in transgenic embryos.
• Assessment of stress tolerance (UV irradiation) in transgenic and morpholino-injected zebrafish.

Main Results:

• Overexpression of pro-caspase-3 led to high caspase activity, extensive apoptosis, and significant morphological defects in zebrafish embryos (eyes, notochord, heart, yolk sac).
• Transgenic fish showed reduced eye size, retinal degeneration, heart failure, and increased sensitivity to UV stress.
• Caspase-3 deficiency via morpholino injection repressed apoptosis and improved stress tolerance.

Conclusions:

• Enhanced pro-caspase-3 processing significantly impacts zebrafish embryogenesis, affecting morphogenesis and stress tolerance.
• The caspase-3-mediated apoptotic pathway is critical for regulating apoptosis and stress response during zebrafish development.
• Caspase-3 plays a vital role in normal embryonic development and stress adaptation.