The F-box gene Ppa promotes lipid storage in Drosophila

Lipid is one of the important components of living organisms. The precise regulation and homeostasis maintenance of lipid metabolism are essential to human health. The ubiquitination pathway regulates lipid metabolism by degrading lipid-related proteins. Ppa encodes an F-box protein, which is a member of the SCF ubiquitination complex. Previous studies reported that Ppa regulated the body segmentation and the correct localization of centromere histones, while its function in lipid metabolism has not been reported. In this study, Drosophila melanogaster was used to explore the function of Ppa in lipid storage. The subcellular localization of PPA was detected by fusion with green fluorescent protein. The deletion mutant of Ppa was constructed via CRISPR/Cas9 technology. The morphological changes of lipid droplets in deletion mutants and Ppa overexpression flies were analyzed by BODIPY 493/503 or Nile red staining. Further, Ppa was overexpressed in the deletion mutant to verify its function. The results showed that PPA-GFP fusion protein were localized in the nuclei of salivary gland and fat body. Compared with the control flies, the lipid droplets in Ppa deletion mutants became smaller, and overexpression of Ppa exhibited larger lipid droplets. Overexpression of Ppa in the deletion mutant could restore the lipid droplets to normal state. In summary, this study demonstrated that Ppa could promote lipid storage in Drosophila.