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bioRxiv · 10.1101/2024.03.22.586318

Activity of zebrafish THAP9 transposase and zebrafish P element-like transposons

Kutnowski, N.·Ghanim, G. E.·Lee, Y.·Rio, D.
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Abstract

Transposable elements are mobile DNA segments that are found ubiquitously across the three domains of life. One family of transposons, called P elements, were discovered in the fruit fly Drosophila melanogaster. Since their discovery, P element transposase-homologous genes (called THAP-domain containing 9 or THAP9) have been discovered in other animal genomes. Here, we show that the zebrafish (Danio rerio) genome contains both an active THAP9 transposase (zfTHAP9) and mobile P-like transposable elements (called Pdre). zfTHAP9 transposase can excise one of its own elements (Pdre2) and Drosophila P elements. Drosophila P element transposase (DmTNP) is also able to excise the zebrafish Pdre2 element, even though its distinct from the Drosophila P element. However, zfTHAP9 cannot transpose Pdre2 or Drosophila P elements, indicating partial transposase activity. Characterization of the N-terminal THAP DNA binding domain of zfTHAP9 shows distinct DNA binding site preferences from DmTNP and mutation of the zfTHAP9, based on known mutations in DmTNP, generated a hyperactive protein. These results define an active vertebrate THAP9 transposase that can act on the endogenous zebrafish Pdre and Drosophila P elements.

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Kutnowski, N., Ghanim, G. E., Lee, Y., Rio, D.. 2024-03-22. Activity of zebrafish THAP9 transposase and zebrafish P element-like transposons. https://doi.org/10.1101/2024.03.22.586318

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