MicroRNA clusters co-operate during metamorphosis in male and female Drosophila

Metamorphosis is a key biological event that occurred during insect evolution and allows them to successfully dominate the terrestrial habitats. Sesquiterpenoid hormones including juvenile hormone is well known to be a key player involved in insect metamorphosis. The precise roles of noncoding RNAs, such as microRNAs, that control insect metamorphosis and sesquiterpenoids are not well understood. Here we utilised the fruit fly Drosophila melanogaster and demonstrated a microRNA cluster miR-277/34 regulates the sesquiterpenoid pathway genes. CRISPR mutants deleting miR-277, miR-34, and miR-277/34 further showed that members in the cluster are involved in the control of different sexes to insect emergence and completion of metamorphosis. This study shows that microRNA cluster contributes to insect sexual dimorphism during metamophosis via differences of duration development between males and females.