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bioRxiv · 10.1101/123703

A Role For The F-Box Protein HAWAIIAN SKIRT In Plant miRNA Function

Lang, P.·Christie, M.·Dogan, E.·Schwab, R.·Hagmann, J.·Van de Weyer, A.-L.·Weigel, D.
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Abstract

As regulators of gene expression in multicellular organisms, microRNAs (miRNAs) are crucial for growth and development. While a plethora of factors involved in their biogenesis and action in Arabidopsis thaliana have been described, these processes and their fine-tuning are not fully understood in plants. Here, we used plants expressing an artificial miRNA target mimic (MIM) to screen for negative regulators of miR156 activity. We identified a new mutant allele of the F-box protein HAWAIIAN SKIRT (HWS; At3G61590), hws-5, as a suppressor of the MIM156-induced developmental and molecular phenotypes. In hws plants, levels of endogenous miRNAs are increased and their mRNA targets decreased. Plants constitutively expressing full-length HWS - but not a truncated version lacking the F-box domain - display morphological and molecular phenotypes resembling those of mutants defective in miRNA biogenesis and activity. In combination with such mutants, hws loses its delayed floral organ abscission ( skirt) phenotype, suggesting epistasis. Also, the overall hws transcriptome profile partially resembles well-known miRNA mutants hyl1-2 and se-3, indicating action in a common pathway. We thus propose HWS as a novel, F-box dependent regulator of miRNA biogenesis.\n\nSummary statementHAWAIIAN SKIRT is a regulator of Arabidopsis thaliana microRNA biogenesis and acts in an F-box-dependent manner.

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Lang, P., Christie, M., Dogan, E., Schwab, R., Hagmann, J., Van de Weyer, A.-L., Weigel, D.. 2017-04-03. A Role For The F-Box Protein HAWAIIAN SKIRT In Plant miRNA Function. https://doi.org/10.1101/123703

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