<i>miR-125-chinmo</i> pathway regulates dietary restriction-dependent enhancement of lifespan in <i>Drosophila</i>.

Abstract

Dietary restriction (DR) extends healthy lifespan in diverse species. Age and nutrient-related changes in the abundance of microRNAs (miRNAs) and their processing factors have been linked to organismal longevity. However, the mechanisms by which they modulate lifespan and the tissue-specific role of miRNA-mediated networks in DR-dependent enhancement of lifespan remains largely unexplored. We show that two neuronally enriched and highly conserved microRNAs, <i>miR-125</i> and <i>let-7</i> mediate the DR response in <i>Drosophila melanogaster</i>. Functional characterization of <i>miR-125</i> demonstrates its role in neurons while its target <i>chinmo</i> acts both in neurons and the fat body to modulate fat metabolism and longevity. Proteomic analysis revealed that Chinmo exerts its DR effects by regulating the expression of <i>FATP, CG2017, CG9577, CG17554, CG5009, CG8778, CG9527</i>, and <i>FASN1</i>. Our findings identify <i>miR-125</i> as a conserved effector of the DR pathway and open the avenue for this small RNA molecule and its downstream effectors to be considered as potential drug candidates for the treatment of late-onset diseases and biomarkers for healthy aging in humans.