Polycomb-mediated silencing of miR-8 is required for maintenance of intestinal stemness in Drosophila melanogaster

• Published in: Nature communications Vol. 15; no. 1; p. 1924
• Main Authors: Veneti, Zoe, Fasoulaki, Virginia, Kalavros, Nikolaos, Vlachos, Ioannis S, Delidakis, Christos, Eliopoulos, Aristides G
• Format: Journal Article
• Language: English
• Published: England Nature Publishing Group 02.03.2024; Nature Portfolio
• Subjects: Ablation; Animals; Cell differentiation; Cell self-renewal; Differentiation; Drosophila melanogaster; Drosophila melanogaster - genetics; Drosophila Proteins - genetics; Enterocytes; Epigenetics; Female; Fruit flies; Histone H3; Histones; Homeostasis; Insects; Intestine; Intestines; Maintenance; Methylation; MicroRNAs - genetics; miRNA; Polycomb group proteins; Polycomb Repressive Complex 2 - genetics; Ribonucleic acid; RNA; RNA-mediated interference; Stem cells
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-024-46119-9

Balancing maintenance of self-renewal and differentiation is a key property of adult stem cells. The epigenetic mechanisms controlling this balance remain largely unknown. Herein, we report that the Polycomb Repressive Complex 2 (PRC2) is required for maintenance of the intestinal stem cell (ISC) pool in the adult female Drosophila melanogaster. We show that loss of PRC2 activity in ISCs by RNAi-mediated knockdown or genetic ablation of the enzymatic subunit Enhancer of zeste, E(z), results in loss of stemness and precocious differentiation of enteroblasts to enterocytes. Mechanistically, we have identified the microRNA miR-8 as a critical target of E(z)/PRC2-mediated tri-methylation of histone H3 at Lys27 (H3K27me3) and uncovered a dynamic relationship between E(z), miR-8 and Notch signaling in controlling stemness versus differentiation of ISCs. Collectively, these findings uncover a hitherto unrecognized epigenetic layer in the regulation of stem cell specification that safeguards intestinal homeostasis.