A polycistronic locus encodes both a tumor-suppressive microRNA, and a long non-coding RNA regulating testis morphology in Drosophila

Using the testes of Drosophila melanogaster as a proven model for investigating these processes, we identified a polycistronic locus from which two non-coding transcripts, miR-317 and the long non-coding RNA (lncRNA) Peony, are produced, with alternative polyadenylation implicated in regulation of their differential expression levels.

We report here that each transcript has a distinct role in Drosophila testes; the absence of miR-317 leads to the emergence of germ-cell tumors in developing flies, and the increased expression of Peony results in the disruption of the muscle sheath covering the testis. We also show that miR-317 deficiency increases Notch signaling activity in somatic cyst cells, upregulates multiple predicted targets of miR-317, and drives germline tumorigenesis.