MicroRNA miR-252 targets chitinase and sesquiterpenoid hormonal pathway genes of Drosophila

Sesquiterpenoid hormones such as juvenile hormone play critical roles in insect development and reproduction, but there are few studies revealing the roles of noncoding RNAs such as microRNAs for controlling its pathway genes. Here we dissected how miR-252 modulates the development in Drosophila melanogaster by genetic screening and transcriptomic analysis. We found that overexpression of miR-252 resulted in larval and pupal lethality, metamorphic failure and male genital deformity, which recapitulated the phenotypes resulted from sesquiterpenoid hormone imbalance. Transcriptomic analysis revealed the gene regulatory pathways such as molting cycle were disturbed by miR-252 in the 3rd instar larvae. Moreover, the qPCR detection and dual luciferase reporter assays demonstrated that miR-252 could regulate the expression of genes involved in the sesquiterpenoid juvenile hormone and ecdysteroid pathways, as well as chitinase. This study expanded our understanding of microRNAs involved in regulation of genes involved in Drosophila development and endocrine systems.