Transgenerational adaptation to hypoxia

TL;DR

The study shows that worms can adapt across generations to repeated stress, like low oxygen, and this adaptation depends on specific genetic mechanisms.

Contribution

The study reveals transgenerational adaptation to repeated hypoxia and identifies the role of H3K27me3 in this process.

Findings

Repeated hypoxia exposure across generations eliminates lifespan extension and fertility reduction in worms.

Transgenerational adaptation occurs in response to glucose availability changes.

The PRC2 complex and H3K27me3 are critical for transgenerational adaptation to hypoxia.

Abstract

Epigenetic inheritance alerts naïve descendants to prepare for stresses that could still be present, whereas distant descendants return to a basal state after several generations without stress. However, organisms are frequently exposed to stresses successively across generations. We found that parental hypoxia exposure increased P0 longevity, caused intergenerational lipid reduction, and elicited transgenerational fertility reduction that was dependent on generationally transmitted small RNAs. Here, we find that Caenorhabditis elegans adapt to repeated generational stresses. We show that, upon two repeated generational hypoxia exposures, the life-span extension is eliminated, and after four repeated generational hypoxia exposures, the reduced fertility is eliminated. Transgenerational adaptation also occurred in response to changes in glucose availability. Transgenerational hypoxia adaptation is dependent on the H3K27 trimethyltransferase PRC2 complex, and we identified transgenerationally adapted genes. Our findings reveal that transgenerational adaptation occurs and suggest that H3K27me3 is a critical modification for adapting to repeated generational stresses.

Demonstration of adaptation on a multigenerational scale to repeated stresses.

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