Ppl gal4

Flies were reared at 25 °C with a 12:12 h light/dark cycle on standard food unless otherwise mentioned. Ingredients of various foods are included in Supplementary Table 1. For the starvation, high sugar, and high-fat diet assays, flies were raised on standard food and then transferred to the relevant diet for 24 h before dissection of the fat body and TAG measurements. For lifespan tests, flies were raised on standard, poor nutrition, or high nutrition food throughout the adult stage. P{nos-Cas9.R}attP2 is the background stock (control) of deletion mutants (Bloomington Drosophila Stock Center/BDSC 78782). For targeted knockdown, overexpression and rescue experiments, the fat body-specific Gal4 drivers ppl-Gal4 (BDSC 58768) and LPP-Gal4^{55 (link)} were used. UAS-GFP (BDSC 4775, 4776) driven by ppl-Gal4 was used as control. arlr–RNAi⁶¹⁹⁹⁷ (BDSC 61997) and arlr–RNAi¹⁴⁸⁷⁴ (Vienna Drosophila Resource Center/VDRC v14874) were used to knockdown arlr. dendoU–RNAi (VDRC v9916) was used to knockdown dendoU. Lsd-1–RNAi, regucalcin–RNAi, yip2–RNAi, and CG5162–RNAi (TsingHua Fly Center/THFC TH04820.N, THU1799, THU3344, and TH03231.N, respectively) were used for the genetic interaction tests with arlr mutants. UAS-KDEL-mCherry, used to label the ER, was a gift from Yixian Cui (Wuhan University, Wuhan, China).

All fly stocks were maintained at 25°C on standard medium unless otherwise stated. The following fly lines were used in this study: UAS-sna⁺ (FlyORF F000066), UAS-esg⁺ (FlyORFF000254), UAS-wor⁺ (FlyORF F000155), UAS-sna^RNAi (BDSC BL28679), UAS-esg^RNAi (BDSC BL42846), UAS-wor^RNAi (VDRC v6248), UAS-lsd1^RNAi (BDSC BL65020), UAS-lsd2^RNAi (BDSC BL32846), UAS-lsd1⁺ (BDSC BL31784), UAS-lsd2⁺ (BDSC BL19733), Ppl-Gal4 (BDSC BL58768), R4-Gal4 (BDSC BL 33832), caudal (Cd)-Gal4 (BDSC BL3042), w1118 (BDSC BL 6326), and tPGH (BDSC BL 8164). Tubulin-Gal80^ts (BDSC BL7180). Hand-Gal4 is a gift from Lauren Perrin (AMU, France), and Myo1A-Gal4 is a gift from Bruce Edgar (University of Utah).