Skip to main content
. 2023 Sep 16;26(10):107960. doi: 10.1016/j.isci.2023.107960

Figure 4.

Figure 4

Lipid droplets modulate ubiquitinated protein accumulation, SQST-1 levels, and lifespan

(A) Lifespan analysis of wild-type and transgenic animals over-expressing ATGL-1:GFP developmentally raised at 20°C and then grown at 25°C during adulthood on OP50 E. coli (n = 100).

(B) Levels of RFP signal and lipid droplets from Day 3 animals over-expressing SQST-1:RFP in wild-type or transgenic ATGL-1:GFP over-expressing background.

(C) Wild-type and ATGL-1:GFP over-expressing animals were raised at 20°C and then grown at 25°C during adulthood on control bacteria (Ctl) or bacteria expressing dsRNA against autophagy gene lgg-1 or proteasome subunit gene rpn-6.1 for 2 days. Levels of ubiquitinated proteins and actin were visualized by immunoblotting. Actin was used as loading control. Biological replicates shown.

(D) Animals expressing lipid droplet-resident protein DHS-3 fused to GFP were raised at 20°C and then grown at 25°C during adulthood on control bacteria or bacteria expressing RNAi against lgg-1 or rpn-6 for 4 days. Levels of ubiquitinated proteins and DHS-3:GFP were visualized by immunoblotting from total input (I), cytosol (C) and lipid droplet (LD) fractions (comparative % loaded between fractions, i.e., 10%).

(E) Day 1 wild-type animals were fed control bacteria or bacteria expressing dsRNA against rpn-6 or atgl-1 for 3 days and ubiquitination levels were detected by immunoblotting.

(F) Levels of RFP signal and lipid droplets in Day 7 daf-2 animals over-expressing SQST-1:RFP and fed control bacteria or bacteria expressing dsRNA against lpin-1 during adulthood.

(G) Day 1 daf-2 animals were fed control bacteria or bacteria expressing dsRNA against atgl-1, rpn-6 or lpin-1 for 5 days at 25°C and ubiquitination levels were detected by immunoblotting. Actin was used as loading control. Biological replicates shown.

(H) Lifespan analysis of wild-type and daf-2(e1370) raised at 20°C on OP50 E. coli and then grown at 25°C during adulthood on control bacteria or bacteria expressing dsRNA against lpin-1 (n = 100). Details about lifespan analyses and repeats are available in Tables S3 and S4, Mantel-Cox log rank. n.s.: not significant, ∗p < 0.05,∗∗∗∗p < 0.001.