The evolution of an RNA-based memory of self in the face of genomic conflict

Pliota, P.; Marvanova, H.; Koreshova, A.; Kaufman, Y.; Tikanova, P.; Krogull, D.; Hagmueller, A.; Widen, S. A.; Handler, D.; Gokcezade, J.; Duchek, P.; Brennecke, J.; Ben-David, E.; Burga, A.

doi:10.1101/2022.06.17.496645

bioRxiv · 10.1101/2022.06.17.496645

The evolution of an RNA-based memory of self in the face of genomic conflict

Pliota, P.·Marvanova, H.·Koreshova, A.·Kaufman, Y.·Tikanova, P.·Krogull, D.·Hagmueller, A.·Widen, S. A.·Handler, D.·Gokcezade, J.·Duchek, P.·Brennecke, J.·Ben-David, E.·Burga, A.

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Abstract

Distinguishing endogenous genes from selfish ones is essential for germline integrity. In animals, small regulatory RNAs play a central role in this process; however, the underlying principles are largely unknown. To fill this gap, we studied how selfish toxin-antidote elements (TAs) evade silencing in the nematode Caenorhabditis tropicalis. We found that the slow-1/grow-1 TA is active only when maternally inherited. Surprisingly, this parent-of-origin effect stems from a regulatory role of the toxins mRNA: maternal slow-1 mRNA--but not SLOW-1 protein--licenses slow-1 expression in the zygote by counteracting piRNAs. Our results indicate that epigenetic licensing-- known to play a role in C. elegans sex-determination--is likely a common mechanism that hinders the spread of selfish genes in wild populations while ensuring a lasting memory of self in the germline.

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Pliota, P., Marvanova, H., Koreshova, A., Kaufman, Y., Tikanova, P., Krogull, D., Hagmueller, A., Widen, S. A., Handler, D., Gokcezade, J., Duchek, P., Brennecke, J., Ben-David, E., Burga, A.. 2022-06-20. The evolution of an RNA-based memory of self in the face of genomic conflict. https://doi.org/10.1101/2022.06.17.496645

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