Project description:4 weeks old rooted plantlets (P. tremula × tremuloides) of wildtype (T89), PICKLE:RNAi (line 417-4 and 417-17) and FDL2:RNAi (line 510-12 and 510-18) were potted in soil in 1.5 l pots and were kept in a glass chamber. The plants were grown for eight weeks and well irrigated before the treatment started. Well-watered and drought stress treatments were applied. Woody samples were collected after 4 weeks of treatment for RNA extraction and RNA sequencing.
Project description:Identifying resistance mutations in a drug target provides crucial information. Lentiviral transduction creates multiple types of mutations due to the error-prone nature of the HIV-1 reverse transcriptase (RT). We optimized and leveraged this property to identify drug resistance mutations, a technique we term LentiMutate. After validating this technique by identifying clinically relevant EGFR resistance mutations, we applied this technique to two additional anti-cancer drugs, imatinib and AMG 510. We find novel deletions in BCR-ABL1 that confer resistance to BCR-ABL1 inhibitors and point mutations in the AMG 510 binding pocket or oncogenic non-G12C mutations, in KRAS-G12C or wild-type KRAS, respectively, that confer resistance to AMG 510. LentiMutate may prove highly valuable to clinical and preclinical cancer drug development.
Project description:Caloric restriction (CR) is one of the most robust interventions shown to delay aging in diverse species, including rhesus monkeys (Macaca mulatta). Identification of factors involved in CR brings a promise of translatability to human health and aging. Here, we show that CR induced a profound change in abundance of circulating microRNAs (miRNAs) linked to growth and insulin signaling pathway, suggesting that miRNAs are involved in CR’s mechanisms of action in primates. Deep sequencing of plasma RNA extracts enriched for short species revealed a total of 243 unique species of miRNAs including 47 novel species. Approxi- mately 70% of the plasma miRNAs detected were conserved between rhesus monkeys and humans. CR induced or repressed 24 known and 10 novel miRNA species. Regression analysis revealed correlations between bodyweight, adiposity, and insulin sensitivity for 10 of the CR-regulated known miRNAs. Sequence alignment and target identification for these 10 miRNAs identify a role in signaling downstream of the insulin receptor. The highly abundant miR-125a-5p correlated positively with adiposity and negatively with insulin sensitivity and was negatively regulated by CR. Putative target pathways of CR- associated miRNAs were highly enriched for growth and insulin signaling that have previously been implicated in delayed aging. Clustering analysis further pointed to CR-induced miRNA regula- tion of ribosomal, mitochondrial, and spliceosomal pathways. These data are consistent with a model where CR recruits miRNA- based homeostatic mechanisms to coordinate a program of delayed aging.
Project description:Identifying resistance mutations in a drug target provides crucial information. Lentiviral transduction creates multiple types of mutations due to the error-prone nature of the HIV-1 reverse transcriptase (RT) and we show this property can be leveraged to identify mutations that confer resistance to targeted anti-cancer drugs, a technique we term “LentiMutate”. First, we improved LentiMutate by making the lentiviral RT more error-prone. Next, we applied this technique to two anti-cancer drugs, imatinib and AMG 510. We find novel deletions in BCR-ABL that confer resistance to BCR-ABL inhibitors and point mutations in the AMG 510 binding pocket or oncogenic non-G12C mutations, in KRAS-G12C or wild-type KRAS, respectively, that confer resistance to AMG 510. LentiMutate may prove highly valuable to clinical and preclinical cancer drug development
Project description:Identifying resistance mutations in a drug target provides crucial information. Lentiviral transduction creates multiple types of mutations due to the error-prone nature of the HIV-1 reverse transcriptase (RT) and we show this property can be leveraged to identify mutations that confer resistance to targeted anti-cancer drugs, a technique we term “LentiMutate”. First, we improved LentiMutate by making the lentiviral RT more error-prone. Next, we applied this technique to two anti-cancer drugs, imatinib and AMG 510. We find novel deletions in BCR-ABL that confer resistance to BCR-ABL inhibitors and point mutations in the AMG 510 binding pocket or oncogenic non-G12C mutations, in KRAS-G12C or wild-type KRAS, respectively, that confer resistance to AMG 510. LentiMutate may prove highly valuable to clinical and preclinical cancer drug development
Project description:Calorie restriction (CR) provides anti-aging benefits through diverse processes, such as reduced metabolism and growth and increased mitochondrial activity. Although controversy still exists regarding CR-mediated lifespan effects, many researchers are seeking interventions that mimic the effects of CR. Yeast has proven to be a useful model system for aging studies, including CR effects. We report here that yeast adapted through in vitro evolution to the severe cellular stress caused by loss of the Ulp2 SUMO-specific protease exhibit both enhanced growth rates and replicative lifespan, and they have altered gene expression profiles similar to those observed in CR. Notably, in certain evolved ulp2Δ lines, a dramatic increase in the auto-sumoylation of Ubc9 E2 SUMO-conjugating enzyme results in altered regulation of multiple targets involved in energy metabolism and translation at both transcriptional and post-translational levels. This increase is essential for the survival of aged cells and CR-mediated lifespan extension. Thus, we suggest that high Ubc9 auto-sumoylation exerts potent anti-aging effects by promoting efficient energy metabolism-driven improvements in cell replication abilities. This potential could be therapeutically explored for the development of novel CR-mimetic strategies.
Project description:Although caloric restriction (CR) was first shown to extend the lifespan of rodents over 75 years ago, the underlying mechanisms remain unclear. Additionally, the majority of published studies have focused on the effects of short-term CR. To better understand cell signaling alterations in a tissue known to be highly impacted by CR, we sought to assess the impact of aging and lifelong CR on skeletal muscle protein phosphorylation dynamics. We performed phosphoproteomic analysis on skeletal muscle from young mice, old mice fed on an ad libitum diet, and old mice fed a CR diet. This analysis revealed distinct phosphoproteomic signatures associated with both aging and diet. Importantly, CR appeared to promote a signature that was more similar to young mice than old mice fed on an ad lib diet. From the phosphorylation measurements on its known substrates, we deciphered that aging promotes Protein kinase A (PKA) signaling, and CR inhibits this signaling cascade. Given the demonstrated role of PKA signaling as a “pro-aging” pathway in various model organisms, including yeast and mice, we propose that CR exerts its longevity-enhancing effects partially via the suppression of this pathway.