Fig. 3: A feedback loop of ECM homeostasis implicated in longevity.

a Time course of counterbalancing age-related changes in matrisome protein levels by daf-2(RNAi)-longevity intervention. Details in Supplementary Data 9. b Composite of proteomics data showing that distinct longevity interventions increased the normally age-related decrease of collagen levels and dampened the normally age-related elevation of extracellular proteases. Note that individual values of log fold changes (FC) from different proteomics datasets shown here as a composite are not comparable but should indicate the directionality of protein abundance change. For individual volcano plots, data, and details, see Supplementary Data 9. c The collagen over total protein content is displayed as a time course for a spe-9 quasi-wild type population. Boxplot shows the median (black line), 25th/75th percentiles (hinges), and 1.5*IQR (whiskers). 3 independent biological trials. d The collagen over total protein ratio is shown for spe-9 and glp-1 mutant populations at days 0 and 14 of adulthood. Boxplot shows the median (black line), 25th/75th percentiles (hinges), and 1.5*IQR (whiskers). 3 independent biological trials. e Cuticle thickness increases with age based on electron microscopy (EM) images (Source: wormimage.org). Individual C. elegans are represented as dots (EM dataset). Triangles indicate outliers. Boxplot shows the median (black line), 25th/75th percentiles (hinges), and 1.5*IQR (whiskers). P values are One-way ANOVA post hoc Tuckey. See Supplementary Fig. 5 and Supplementary Data 9 for details. f Isogenic population of col-144 promoter GFP (LSD2002 spe-9(hc88); Pcol-144::GFP) C. elegans were split at day 5 of adulthood into high and low expressing GFP individuals. g Collagen COL-120oe (LSD2017) overexpression increased lifespan compared to control (wild type with rol-6(su1006) co-injection marker LSD2013) on UV-inactivated bacteria. h Differences in protein abundance ratios are displayed for COL-120oe and wild-type populations undergoing control and col-120 RNAi treatment. i Overexpression of COL-120oe (LSD2017) increased mRNA levels of other collagens and ECM proteases by qRT-PCR at day 1 of adulthood. N=4 independent biological samples in duplicates (each over 200 L4 worms). Mean + SEM. P values relative to WT were determined by a one-sample t-test, two-tailed, with a hypothetical mean of 1. j Collagen col-10(tm6673) mutation partially suppressed daf-2(e1368) reduced insulin/IGF-1 receptor signaling longevity at 20°C. k Changes in protein abundance ratios are shown for daf-2(e1368), col-10(tm6673), and daf-2(e1368); col-10(tm6673) animals. l The effect of daf-2 RNAi on changes in protein abundance ratios is shown in wild type and dpy-18(ok162) populations. m Prolyl 4-hydroxylase dpy-18(ok162) mutation partially suppressed reduced insulin/IGF-1 receptor signaling longevity upon adulthood-specific knockdown of daf-2 at 20°C. n Model of the extracellular matrix homeostasis feedback loop. Created with BioRender.com. f, g, j, m For details, raw data, and statistics, see Supplementary Data 7.