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bioRxiv · 10.1101/2023.05.14.540679

ADBP-1 regulates ADR-2 nuclear localization to control editing substrate selection

Eliad, B.·Schneider, N.·Ben-Naim Zgayer, O.·Amichan, Y.·Erdmann, E. A.·Hundley, H. A.·Lamm, A.
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Abstract

Adenosine-to-inosine (A-to-I) RNA editing, catalyzed by ADAR enzymes, is a prevalent and conserved RNA modification. While A-to-I RNA editing is essential in mammals, in Caenorhabditis elegans, it is not, making them invaluable for RNA editing research. In C. elegans, ADR-2 is the sole catalytic A-to-I editing enzyme, and ADR-1 is an RNA editing regulator. ADAR localization is well-studied in humans but not well-established in C. elegans. In this study, we examine the cellular and tissue-specific localization of ADR-2. We show that while ADR-2 is present in most cells in the embryo, at later developmental stages, its expression is both tissue- and cell-type-specific. Additionally, both ADARs are mainly in the nucleus. ADR-2 is adjacent to the chromosomes during the cell cycle. We show that the nuclear localization of endogenous ADR-2 depends on ADBP-1, not ADR-1. In adbp-1 mutant worms, ADR-2 is mislocalized, while ADR-1 is not, leading to decreased editing levels and de-novo editing, mostly in exons, suggesting that ADR-2 is also functional in the cytoplasm. Besides, mutated ADBP-1 affects gene expression. Furthermore, we show that ADR-2 targets adenosines with different surrounding nucleotides in exons and introns. Our findings indicate that ADR-2 cellular localization is highly regulated and affects its function.

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Eliad, B., Schneider, N., Ben-Naim Zgayer, O., Amichan, Y., Erdmann, E. A., Hundley, H. A., Lamm, A.. 2023-05-14. ADBP-1 regulates ADR-2 nuclear localization to control editing substrate selection. https://doi.org/10.1101/2023.05.14.540679

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