Project description:We used RNA-seq to discover that gene expression changes during aging are attenuated in elt-2 overexpressors relative to controls Whole-worm mRNA was sequenced from worms over-expressing elt-2 and control worms. Five biological replicates were collected for each condition.
Project description:We used RNA-seq to identify 162 genes that are differentially-regulated following elt-2 RNAi Whole-worm mRNA was sequenced from elt-2 RNAi- and control-fed worms. Biological triplicates were assay for each condition
Project description:We used RNA-seq to identify 292 genes that are differentially-regulated following elt-2 RNAi Whole-worm mRNA was sequenced from elt-2 RNAi- and control-fed worms. Biological triplicates were assay for each condition
Project description:Transcriptional profiling of adult C.elegans exposed to E.coli or to GFP-expressing P. aeruginosa (strain PA14). For P. aeruginosa exposure, worms were separated into 2 groups - fully colonized (green) or non-colonized (dark). Six conditions ( control or elt-2 RNAi ; E.coli, P. aeurginosa colonized, and P. aeurginosa non-colonized). 2-color arrrays, each sample co-hybridized with the same reference RNA sample from mixed stage C.elegans cultures Worms were either sorted using the wormsorter (WS) or were hand picked (HP) under a fluorescent stereoscope
Project description:We used RNA-seq to assay gene expression changes over time in response to OP50 and PY79 To understand the molecular processes underlying aging, we screened modENCODE ChIP-seq data to identify transcription factors that bind to age-regulated genes in C. elegans. The most significant hit was the GATA transcription factor encoded by elt-2, which is responsible for inducing expression of intestinal genes during embryogenesis. Expression of ELT-2 decreases during aging, beginning in middle age. We identified genes regulated by ELT-2 in the intestine during embryogenesis, and then showed that these developmental genes markedly decrease in expression as worms grow old. Overexpression of elt-2 extends lifespan and slows the rate of gene expression changes that occur during normal aging. Thus, our results identify the developmental regulator ELT-2 as a major driver of normal aging in C. elegans. Whole-worm mRNA was sequenced from E. coli- and B.subtilis-fed worms. For each condidtion, one replicate was sequenced at Day 4 and Day 13
Project description:Mechanical stress is a measure of internal resistance exhibited by a body or material when external forces, such as compression, tension, bending, etc. are applied. The study of mechanical stress on health and aging is a continuously growing field, as major changes to the extracellular matrix and cell-to-cell adhesions can result in dramatic changes to tissue stiffness during aging and diseased conditions. For example, during normal aging, many tissues including the ovaries, skin, blood vessels, and heart exhibit increased stiffness, which can result in a significant reduction in function of that organ. As such, numerous model systems have recently emerged to study the impact of mechanical and physical stress on cell and tissue health, including cell-culture conditions with matrigels and other surfaces that alter substrate stiffness and ex vivo tissue models that can apply stress directly to organs like muscle or tendons. Here, we sought to develop a novel method in an in vivo, model organism setting to study the impact of mechanical stress on aging, by increasing substrate stiffness in solid agar medium of C. elegans. To our surprise, we found shockingly limited impact of growth of C. elegans on stiffer substrates, including limited effects on cellular health, gene expression, organismal health, stress resilience, and longevity. Overall, our studies reveal that altering substrate stiffness of growth medium for C. elegans have only mild impact on animal health and longevity; however, these impacts were not nominal and open up important considerations for C. elegans biologists in standardizing agar medium choice for experimental assays.
Project description:Analysis of differential gene expression in C. elegans adults exposed to three different bacteria: E. coli strain OP50, wild-type P. aeruginosa PA14 and gacA mutant PA14. Samples were analyzed at 4 hours and 8 hours after exposure to the different bacteria. These studies identified C. elegans genes induced by pathogen infection. Experiment Overall Design: Three independent biological replicates were isolated for each treatment. All treatments were performed in parallel.
Project description:The actin cytoskeleton is a three-dimensional scaffold of proteins that is a regulatory, energy-consuming material with dynamic properties shaping the structure and function of the cell. The proper function of actin is required for many cellular pathways, including cell division, autophagy, chaperone function, endocytosis, and exocytosis (1–5). The breakdown of these cellular processes manifests during aging and exposure to stress, which is in part due to the breakdown of the actin cytoskeleton (5–9). However, the regulatory mechanisms involved in preservation of cytoskeletal form and function are not well understood. Here, we performed a multi-pronged, cross-organismal screen combining a whole-genome CRISPR-Cas9 screen in human fibroblasts with in vivo C. elegans synthetic lethality screening. We identified the bromodomain protein, BET-1, as a key regulator promoting actin health and longevity. Interestingly, overexpression of bet-1 preserves actin health at late age and promotes lifespan and healthspan in C. elegans. These beneficial effects are through preservation of actin, downstream of the function of BET-1 as a transcriptional regulator. Together, our discovery attributes assigns a key role of BET-1 in cytoskeletal health, highlighting regulatory cellular networks promoting cytoskeletal homeostasis.
Project description:Small molecule inhibitors of mitochondrial electron transport chain (ETC) hold significant promise in the field of mitochondrial research and aging biology. In this study, we studied two molecules: mycothiazole (MTZ) - isolated from the marine sponge P. mycofijiensis and its semisynthetic acetylated derivative 8-O-acetylmycothiazole (8-OAc) as efficient alternatives for their high efficiency to inhibit ETC complex I function. Similar to rotenone, a widely used complex I inhibitor, these two compounds showed anticancer activity and strikingly demonstrate a lack of toxicity to non-cancer cells, a highly beneficial feature in the development of anti-cancer therapeutics. Furthermore, experiments with these small molecules in vivo utilizing C.elegans demonstrate their additional utilization to aging studies. We observed that both molecules have the ability to induce a mitochondria-specific unfolded protein response (UPRMT) pathway, which extends lifespan of worms when applied in their adult stage. Interestingly, we also found that these two molecules employ different pathways to extend lifespan in worms, where MTZ utilize the transcription factors, ATFS-1 and HSF-1, which are involved in the UPRMT and heat shock response (HSR) pathways, respectively. In opposition,8-OAc only required HSF-1 and not ATFS-1. This observation elucidates an important insight into the functional roles of various protein subunits of ETC complexes and their regulatory mechanisms associated with aging.
Project description:The actin cytoskeleton is a three-dimensional scaffold of proteins that is a regulatory, energy-consuming material with dynamic properties shaping the structure and function of the cell. The proper function of actin is required for many cellular pathways, including cell division, autophagy, chaperone function, endocytosis, and exocytosis (1–5). The breakdown of these cellular processes manifests during aging and exposure to stress, which is in part due to the breakdown of the actin cytoskeleton (5–9). However, the regulatory mechanisms involved in preservation of cytoskeletal form and function are not well understood. Here, we performed a multi-pronged, cross-organismal screen combining a whole-genome CRISPR-Cas9 screen in human fibroblasts with in vivo C. elegans synthetic lethality screening. We identified the bromodomain protein, BET-1, as a key regulator promoting actin health and longevity. Interestingly, overexpression of bet-1 preserves actin health at late age and promotes lifespan and healthspan in C. elegans. These beneficial effects are through preservation of actin, downstream of the function of BET-1 as a transcriptional regulator. Together, our discovery attributes assigns a key role of BET-1 in cytoskeletal health, highlighting regulatory cellular networks promoting cytoskeletal homeostasis.