A single female-specific PIWI-interacting RNA (piRNA) determines sex in the WZ sex determination system of the silkworm Bombyx mori, in which males have two Z sex chromosomes and females have one Z and one W sex chromosome. This W-chromosome-encoded piRNA is produced from a precursor termed Fem. In female embryos, the inhibition of signalling by Fem-derived piRNA induced the production of male-specific splice variants of Bmdsx, the RNA products of which act further downstream in silkworm sex development. The researchers identified a target gene of Fem-derived piRNA on the Z chromosome, which they called Masc. Silencing of Masc is needed for the production of female-specific isoforms of Bmdsx in female embryos, whereas in male embryos the Masc protein regulates dosage compensation and masculinization.
References
Kiuchi, T. et al. A single female-specific piRNA is the primary determiner of sex in the silkworm. Nature 509, 633–636 (2014).
Rights and permissions
About this article
Cite this article
Koch, L. Small RNA determines silkworm sex. Nat Rev Genet 15, 441 (2014). https://doi.org/10.1038/nrg3769
Published:
Issue Date:
DOI: https://doi.org/10.1038/nrg3769