Transgenerational adaptation to hypoxia

Area of Science:

• Epigenetics and transgenerational inheritance
• Stress response and adaptation in model organisms

Background:

• Epigenetic inheritance primes descendants for recurring environmental stresses.
• Organisms often face successive generational stresses, necessitating adaptive mechanisms.
• Previous studies showed parental hypoxia impacts longevity and fertility via small RNAs.

Purpose of the Study:

• To investigate transgenerational adaptation in *Caenorhabditis elegans* to repeated generational stresses.
• To determine the role of epigenetic modifications in adapting to successive environmental challenges.
• To identify molecular mechanisms underlying transgenerational adaptation to hypoxia and nutrient changes.

Main Methods:

• Exposing *Caenorhabditis elegans* to repeated generational hypoxia and altered glucose availability.
• Assessing lifespan, fertility, and lipid levels across generations.
• Investigating the involvement of the H3K27 trimethyltransferase PRC2 complex and identifying adapted genes.

Main Results:

• Repeated generational hypoxia exposures eliminated lifespan extension after two generations and fertility reduction after four generations.
• Transgenerational adaptation was also observed in response to changes in glucose availability.
• Hypoxia adaptation was dependent on the PRC2 complex, with specific genes identified as transgenerationally adapted.

Conclusions:

• Organisms, like *C. elegans*, can adapt to repeated generational stresses.
• H3K27 trimethylation (H3K27me3) is a critical epigenetic modification for adapting to successive environmental stresses.
• Transgenerational adaptation involves the regulation of gene expression through epigenetic mechanisms.