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bioRxiv · 10.1101/2022.12.15.520629

A pan-cnidarian microRNA is an ancient biogenesis regulator of stinging cells

Fridrich, A.·Salinas-Saavedra, M.·Kozlovski, I.·Surm, J. M.·Chrysostomou, E.·Tripathi, A. M.·Frank, U.·Moran, Y.
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Abstract

An ancient evolutionary innovation of a novel cell-type, the stinging cell (cnidocyte), appeared >600 million years ago in the phylum Cnidaria (sea anemones, corals, hydroids, and jellyfish). A complex bursting nano-injector of venom, the cnidocyst, is embedded in cnidocytes and enables cnidarians paralyzing prey and predators, contributing to this phylums evolutionary success. In this work, we show that post-transcriptional regulation by a pan-cnidarian microRNA, miR-2022, is essential for biogenesis of these cells. By manipulation of miR-2022 levels in a transgenic reporter line of cnidocytes in the sea anemone Nematostella vectensis, followed by transcriptomics, single-cell data analysis, prey paralysis assays, and cell sorting of transgenic cnidocytes, we reveal that miR-2022 enables cnidocyte biogenesis, while exhibiting a conserved expression domain with its targets in cnidocytes of other cnidarian species. Thus, here we reveal one of natures most ancient microRNA-regulated processes by studying the functional basis for its conservation.

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Fridrich, A., Salinas-Saavedra, M., Kozlovski, I., Surm, J. M., Chrysostomou, E., Tripathi, A. M., Frank, U., Moran, Y.. 2022-12-19. A pan-cnidarian microRNA is an ancient biogenesis regulator of stinging cells. https://doi.org/10.1101/2022.12.15.520629

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