Project description:Larvae were reared on standard diet until early third instar, at which time they were washed and transferred to standard diet lacking yeast. The animals remained on this diet until four days after emergence, when one group of adults was switched back to standard diet containing yeast (group Y) while another remained on the diet lacking yeast (group NY). Flies from both groups were killed every hour for the next twelve hours, creating 24 samples across the two treatments. In addition, four samples of flies were killed just before the start of the time course and used as baseline replicates for the no yeast (NY) and yeast (Y) treatments. Baseline replicates were temporally ordered as noted for change-point analysis. No yeast (NY) treatment samples at hours four and eight did not yield microarray data due to insufficient RNA. Total RNA was extracted from whole animals using Trizol (Invitrogen). Sample processing and microarray hybridization/scanning were performed at the Brown University Center for Genetics and Genomics according to Affymetrix protocol. Change-point Analysis Results Table: Results of running change-point analysis on dChip normalized data. Normalized data was transformed into yeast (Y):no yeast (NY) signal ratios, and change-point analysis was performed by GeneTrace on these ratios (see publication for more information on change-point analysis). Raw Data, Not Normalized Table: Raw data (not normalized). Image files were analyzed by Affymetrix Microarray Suite (MAS) 5.0 with no normalization and no scaling. Signal abundance measurements, present [P], marginal [M], or absent [A] calls, and detection p-values reported were all produced by MAS 5.0. Note that there is no data for no yeast (NY) treatment samples at hours 4 and 8 due to insufficient RNA yield. Keywords = insulin, diet, nutrition Keywords: other
Project description:Barth syndrome (BTHS) is a rare X-linked recessively inherited disorder caused by variants in the TAFAZZIN gene. The pathogenic variants lead to impaired conversion of monolysocardiolipin (MLCL) into mature phospholipid cardiolipin (CL). The accumulation of MLCL and mature CL deficiency is a diagnostic marker for BTHS. The clinical spectrum includes cardiomyopathy, skeletal myopathy, neutropenia, and delays in growth. In severely affected BTHS patients, the cardiac phenotype is early onset, heterogeneous and unpredictable. Ultimately, these patients may require a cardiac transplant early in their life. Unfortunately, the pathophysiological mechanisms of BTHS are poorly understood, and treatment options for BTHS remain symptomatic. In this study, we analysed heart samples from five paediatric male BTHS individuals (5 month-15 years old) and compared them to tissues from 24 non-failing donors (19-71 years old) using a newly developed integrated omics method that combines metabolomics, lipidomics and proteomics using a single sample. This comprehensive analysis confirms expected changes in established diagnostic markers such as CL and MLCL, as well as severe and pleiotropic alterations in mitochondrial phenotype and metabolic output, a substrate shift in energy metabolism, and an elevation of heart-failure markers. It also reveals striking interindividual differences between BTHS individuals. Combined, we describe a powerful analytical tool for the in-depth analysis of metabolic disorders and a solid foundation for the understanding of BTHS disease phenotypes in cardiac tissues.
Project description:We identified a molecule in a synthetic lethal screen with ira2Δ in yeast called Y100. Y100 targets ira2Δ deficient yeast and inhibits NF1-deficient tumor cells. Y100 disrupts proteostasis, metabolic homeostasis, and induces the formation of mitochondrial superoxide in NF1 deficient cancer cells. Here, we examined the transcriptional response following treatment with Y100 or a vehicle control.
Project description:Centromeres ensure accurate chromosome segregation, yet their DNA evolves rapidly across eukaryotes, leaving the origin of new centromere architectures unresolved. In the brewer’s yeast Saccharomyces cerevisiae (order Saccharomycetales), compact, genetically defined “point” centromeres replaced large, repeat-rich, epigenetically specified centromeres, but how this transition occurred has been unclear. Competing models have proposed either descent with modification from ancestral epigenetic centromeres or acquisition from selfish plasmid DNA. Here we map and characterize centromeres in the sister order Saccharomycodales and identify evolutionarily related “proto-point” centromeres that bridge repeat-rich and point centromeres. Proto-point centromeres contain a single centromeric nucleosome positioned over an AT-rich core, but retain relaxed organization and sequence variability in flanking cis-elements. In two species, including Saccharomycodes ludwigii, proto-point centromeres are embedded within clusters of Ty5 long terminal repeat (LTR) retrotransposons, and their core CDEII and flanking motifs share sequence similarity to Ty5 LTR sequence. Comparative genomics, synteny, and phylogenetic analyses across multiple yeast orders show that Ty5-cluster centromeres are ancient genomic features and support a model in which proto-point and point centromeres evolved by co-option of Ty5 LTR sequences in an ancestor with retrotransposon-rich centromeres, rather than by horizontal transfer from the 2-µm plasmid. These results indicate that yeast point centromeres are direct descendants of retrotransposons and illustrate how transposable elements can be repurposed to create genetically encoded centromeres.
Project description:In this study, we present the first genome-wide recombination map for mitochondrial DNA in yeast. We also assess the impact of the genetic background and of several gene deletions on the recombination profiles.