A Sex Chromosome piRNA Promotes Robust Dosage Compensation and Sex Determination in C. elegans

UMMS Affiliation

RNA Therapeutics Institute; Program in Bioinformatics and Integrative Biology

Publication Date


Document Type



Biochemistry, Biophysics, and Structural Biology | Bioinformatics | Computational Biology | Developmental Biology


In metazoans, Piwi-related Argonaute proteins engage piRNAs (Piwi-interacting small RNAs) to defend the genome against invasive nucleic acids, such as transposable elements. Yet many organisms-including worms and humans-express thousands of piRNAs that do not target transposons, suggesting that piRNA function extends beyond genome defense. Here, we show that the X chromosome-derived piRNA 21ux-1 downregulates XOL-1 (XO Lethal), a master regulator of X chromosome dosage compensation and sex determination in Caenorhabditis elegans. Mutations in 21ux-1 and several Piwi-pathway components sensitize hermaphrodites to dosage compensation and sex determination defects. We show that the piRNA pathway also targets xol-1 in C. briggsae, a nematode species related to C. elegans. Our findings reveal physiologically important piRNA-mRNA interactions, raising the possibility that piRNAs function broadly to ensure robust gene expression and germline development.


Caenorhabditis briggsae, Caenorhabditis elegans, dosage compensation, piRNAs, sex determination, small RNAs

DOI of Published Version



Dev Cell. 2018 Mar 26;44(6):762-770.e3. doi: 10.1016/j.devcel.2018.01.025. Epub 2018 2018 Feb 15. Link to article on publisher's site

Journal/Book/Conference Title

Developmental cell

Related Resources

Link to Article in PubMed

PubMed ID