*2.7. Electron Microscopy*

*Drosophila* flight muscles were dissected in PBS and fixed in 2% (*w*/*v*) glutaraldehyde and 2.5% (*w*/*v*) formaldehyde in PBS. Embedding, thin sectioning, and staining were carried out according to a standard protocol [22] (n = 5 independent preparations).

#### *2.8.* Drosophila *Survivorship (Life Span Assays)*

Flies were collected upon eclosure and reared in vials (30 flies in each vial, n = 3 independent assays) with food at 25 ◦C or 29 ◦C on a standard medium. The media was changed every 3 days and a number of deaths were recorded until all the flies died (for every life span assay, we used at least n ≥ 20 flies per vial and 3 such vials as biological replicates).
