Project description:Utilization of specific codons varies significantly across organisms. Cancer represents a model for understanding DNA sequence evolution and could reveal causal factors underlying codon evolution. We found that across human cancer, arginine codons are frequently mutated to other codons. Moreover, arginine restriction-a feature of tumor microenvironments-is sufficient to induce arginine codon-switching mutations in human colon cancer cells. Such DNA codon switching events encode mutant proteins with arginine residue substitutions. Mechanistically, arginine limitation caused rapid reduction of arginine transfer RNAs and the stalling of ribosomes over arginine codons. Such selective pressure against arginine codon translation induced a proteomic shift towards low arginine codon containing genes, including specific amino acid transporters, and caused mutational evolution away from arginine codons-reducing translational bottlenecks that occurred during arginine starvation. Thus, environmental availability of a specific amino acid can influence DNA sequence evolution away from its cognate codons and generate altered proteins.
Project description:Utilization of specific codons varies between organisms. Cancer represents a model for understanding DNA sequence evolution and could reveal causal factors underlying codon evolution. We found that across human cancer, arginine codons are frequently mutated to other codons. Moreover, arginine limitation-a feature of tumor microenvironments-is sufficient to induce arginine codon-switching mutations in human colon cancer cells. Such DNA codon switching events encode mutant proteins with arginine residue substitutions. Mechanistically, arginine limitation caused rapid reduction of arginine transfer RNAs and the stalling of ribosomes over arginine codons. Such selective pressure against arginine codon translation induced an adaptive proteomic shift toward low-arginine codon-containing genes, including specific amino acid transporters, and caused mutational evolution away from arginine codons-reducing translational bottlenecks that occurred during arginine starvation. Thus, environmental availability of a specific amino acid can influence DNA sequence evolution away from its cognate codons and generate altered proteins.
Project description:The synthetic lethal relationship between MYC and SAE2 has been previously described in FC-MYC cells using RNAi (Littler et al., 2019). Building on this work, we conducted transcriptomic analysis on MYC-low and MYC-high cells following inhibition of SUMOylation with the SAE1/2 inhibitor, ML-792 (SAEi). FC-MYC cells were grown for twenty-four hours in the absence (MYC-low) and presence (MYC-high) of 500ng/mL tetracycline and treated with either DMSO (vehicle control) or 25 nM SAEi for 24 hours. Three biological replicates were performed for RNAseq analysis, with additional subsets of cells reserved for complementary analyses, including DNA content profiling by flow cytometry and MYC protein expression analysis through western blotting. DNA content analysis showed that SAEi treatment had minimal affect on MYC-low cells but induced polyploidy and apoptosis in MYC-high cells. Western blotting confirmed MYC expression at the protein level as expected. This dataset provides transcriptomic profiles of MYC-low and MYC-high cells under SUMOylation inhibition, offering insights into the differential impact of SAEi on different MYC backgrounds. The dataset also includes analysis of parental RKO cells exposed to the SAEi.
Project description:Purpose:One cause of metabolic syndrome (MetS) is inactivity. This study analyzed the prevalence of MetS due to causes of activity limitation (AL) in adults over 40 years old. Paticipants and Methods:Participants included 2885 people aged 40-79 (1198 men and 1687 women) who completed the Korean National Health and Nutrition Survey (KNHANES) conducted between 2013 and 2017. They were divided into two groups based on age: the middle age group (MA) included 1148 total participants, 515 men and 633 women from 40-59 years old; the older age group (OA) included 1737 total participants, 683 men and 1054 women from 60-79 years old. MetS was diagnosed according to the Third Report of the National Cholesterol Education Program and the Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (NCEP-ATP III). Logistic regression was conducted to calculate the odds ratio for MetS prevalence. Results:The prevalence of MetS in people with AL increased 1.432-fold in the MA men group, 1.511-fold in the OA men group, 1.546-fold in the MA women group, and 1.565-fold in the OA women group. There were several causes of AL; people with physical activity for diabetes mellitus and hypertension increased MetS prevalence in both sexes and all age groups: MA men group (OR=3.216, 95% CI=1.852-7.354, P=0.034), MA women group (OR=2.159, 95% CI=1.854-5.346, P=0.032), OA men group (OR=3.200, 95% CI=1.235-7.841, P=0.009), and OA women group (OR=3.444, 95% CI=1.310-6.627, P=0.008). Also, mental problems in the MA men group (OR=2.284, 95% CI=1.591-4.986, P=0.012) and OA men group (OR=1.149, 95% CI=1.017-2.941, P=0.012), and musculoskeletal problems in the MA women group (OR=1.784, 95% CI=1.102-2.902, P=0.021) and OA women group (OR=1.459, 95% CI=1.054-1.993, P=0.004) increased the prevalence. Conclusion:The prevalence of MetS due to activity limitation was increased in MA and OA groups. Activity limitation increased the MetS prevalence from 1.4- to 1.5-times, Therefore, to prevent metabolic syndrome, physical activity should be increased, and guidelines should be presented according to the activity limitation causes, age, and sex.
Project description:Background/objectivesDecreased plasma concentration of high-density lipoprotein cholesterol (HDL-C) is a risk factor linked to increased risk of cardiovascular disease (CVD). Decreased anti-atherogenic properties of HDL are also implicated in increased CVD risk. The cause is unknown but has been linked to impaired glucose tolerance. The aim of this study was to quantify the modification of HDL by methylglyoxal and related dicarbonyls in healthy people and patients with type 2 diabetes characterise structural, functional and physiological consequences of the modification and predict the importance in high CVD risk groups.Subjects/methodsMajor fractions of HDL, HDL2 and HDL3 were isolated from healthy human subjects and patients with type 2 diabetes and fractions modified by methylglyoxal and related dicarbonyl metabolites quantified. HDL2 and HDL3 were glycated by methylglyoxal to minimum extent in vitro and molecular, functional and physiological characteristics were determined. A one-compartment model of HDL plasma clearance was produced including formation and clearance of dicarbonyl-modified HDL.ResultsHDL modified by methylglyoxal and related dicarbonyl metabolites accounted for 2.6% HDL and increased to 4.5% in patients with type 2 diabetes mellitus (T2DM). HDL2 and HDL3 were modified by methylglyoxal to similar extents in vitro. Methylglyoxal modification induced re-structuring of the HDL particles, decreasing stability and plasma half-life in vivo. It occurred at sites of apolipoprotein A-1 in HDL linked to membrane fusion, intramolecular bonding and ligand binding. Kinetic modelling of methylglyoxal modification of HDL predicted a negative correlation of plasma HDL-C with methylglyoxal-modified HDL. This was validated clinically. It also predicted that dicarbonyl modification produces 2-6% decrease in total plasma HDL and 5-13% decrease in functional HDL clinically.ConclusionsThese results suggest that methylglyoxal modification of HDL accelerates its degradation and impairs its functionality in vivo, likely contributing to increased risk of CVD-particularly in high CVD risk groups.
Project description:Type I interferons (IFN-I) are critical in antimicrobial and antitumor defense. Although IFN-I signal via the interferon-stimulated gene factor 3 (ISGF3) complex consisting of STAT1, STAT2 and IRF9, IFN-I can mediate significant biological effects via ISGF3-independent pathways. For example, absence of STAT1, STAT2 or IRF9 exacerbates neurological disease in transgenic mice with CNS-production of IFN-gamma. Here we determined the role of IFN-I-driven, ISGF3-independent signaling in regulating global gene expression in STAT1, STAT2 or IRF9-deficient murine mixed glial cell cultures (MGCs). Compared with WT, the expression of IFN-gamma-stimulated genes (ISGs) was reduced in number and magnitude in MGCs that lacked STAT1, STAT2 or IRF9. There were significantly fewer ISGs in the absence of STAT1 or STAT2 versus the absence of IRF9. The majority of ISGs regulated in the STAT1-, STAT2- or IRF9-deficient MGCs individually were shared with WT. However, only a minor number of ISGs were common to WT, STAT1-, STAT2- and IRF9-deficient MGCs. While signal pathway activation in response to IFN-gamma was rapid and transient in WT MGCs, this was delayed and prolonged and correlated with increased numbers of ISGs expressed at 12 h versus 4 h IFN-gamma exposure in all three IFN-I-signaling-deficient MGCs. In conclusion, (1) IFN-I can mediate ISG expression in MGCs via ISGF3-independent signaling pathways but with reduced efficiency, with delayed and prolonged kinetics and is more dependent on STAT1 and STAT2 than IRF9, and (2) signaling pathways not involving STAT1, STAT2 or IRF9 play a minor role only in mediating ISG expression in MGCs.
Project description:Genome wide DNA methylation profiling of RKO cells with combination treatments of non-target siRNA or SRCAP siRNA and PBS or 1uM 5-Aza-CdR treatment. The Illumina Infinium 27k Human DNA methylation Beadchip v1.2 was used to obtain DNA methylation profiles across 27,578 CpGs in treated RKO cells. Samples included cells under 4 different treatments. The sample treated with non target siRNA and PBS serves as control sample. Bisulphite converted DNA from the 4 samples were hybridised to the Illumina Infinium 27k Human Methylation Beadchip v1.2
Project description:Mutants of the Mnn1 gene are hyper-sensitive to several stresses and display increased genome instability when subjected to conditions, such as heat shock, generally regarded as non-genotoxic. We describe a role for Menin as a global regulator of heat shock gene expression and critical factor in the maintenance of genome integrity 2-colour microarray design using 36 microarrays testing shock vs non shock in Drosophila melanogaster. Using a test of loss-of-heterozygosity, we show that Drosophila strains lacking a functional Mnn1 gene or expressing a Mnn1 dsRNAi are characterized by increased genome instability in response to short, repeated but non-lethal heat shock or hypoxia treatments. The same was true for strains lacking all Hsp70 genes.