Wine produced at low temperature is often considered to improve sensory qualities. However, there are certain drawbacks to low temperature fermentations: e.g. low growth rate, long lag phase, and sluggish or stuck fermentations. Selection and development of new Saccharomyces cerevisiae strains well adapted at low temperature is interesting for future biotechnological applications. This study aimed to select and develop wine yeast strains that well adapt to ferment at low temperature through evolutionary engineering, and to decipher the process underlying the obtained phenotypes. To this end, we used a pool of 27 commercial yeast strains and set up batch serial dilution experiments to mimic wine fermentation conditions at 12 C. Evolutionary engineering was accomplished by using the natural yeast mutation rate and mutagenesis procedures. One strain (P5) outcompeted the others under both experimental conditions and was able to impose after 200 generations. The evolved strains showed improved growth and low-temperature fermentation performance compared to the ancestral strain. This improvement was acquired only under inositol limitation. The transcriptomic comparison between the evolved and parental strains showed the greatest up-regulation in four mannoprotein coding genes, which belong to the DAN/TIR family (DAN1, TIR1, TIR4 and TIR3). Genome sequencing of the evolved strain revealed the presence of a SNP in the GAA1 gene and the construction of a site-directed mutant (GAA1Thr108) in a derivative haploid of the ancestral strain resulted in improved fermentation performance. GAA1 encodes a GPI transamidase complex subunit that adds GPI, which is required for inositol synthesis, to newly synthesized proteins, including mannoproteins. Thus we demonstrate the importance of inositol and mannoproteins in yeast adaptation at low temperature and the central role of the GAA1 gene by linking both metabolisms.
Evolutionary engineering of a wine yeast strain revealed a key role of inositol and mannoprotein metabolism during low-temperature fermentation.
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View SamplesTo find BMAL1-regulated genes in mice pituitary gland we performed a differential microarray from wild-type vs Bmal1-/- knock-out mice
Chromatin remodeling as a mechanism for circadian prolactin transcription: rhythmic NONO and SFPQ recruitment to HLTF.
Sex, Specimen part
View SamplesPurpose: Nephron progenitor cells generate nephrons, the basic units of kidney. We developed methods to culture mouse and human NPCs in their self-renewal state in vitro with full nephrogenic potentials. The RNA-seq here is used to compare the global gene expression of long-term cultured mouse NPCs and their cognate freshly isolated primary NPCs Methods: mRNA profiles were generated by deep sequencing in duplicate from E11.5, E12.5, E13.5, E16.5 and P1 primary NPCs, and from long-term cultured NPCs derived from E11.5, E13.5, E16.5 and P1 (Passage 20 and Passage 80 for each cell line). To generate rpkm values from raw data, single-end 50bp reads were mapped to the UCSC mouse transcriptome (mm9) by STAR9, allowing for up to 10 mismatches (which is the default by STAR). Only the reads aligned uniquely to one genomic location were retained for subsequent analysis. And expression levels of all genes were estimated by Cufflink10 using only the reads with exact matches. Results: The gene expression levels of the "NPC-signature genes" were firstly transformed as logarithm scales. And then the program “prcomp”, a built-in program for principal component analysis in R packages, was employed with default parameters. We evaluated the variance percentage of each principal component, and found the top 3 components accounted for 84.1% of the total variance, where PC1 accounted for 46.42%, PC2 23.87% and PC3 13.81%. Those three PCs are therefore selected as candidate principal components in the further analysis. Another program “scatterplot3d” in the R packages was used to plot the 3D view of PCA, and “ggplot2” was used in 2D view of PCA. The PCA results indicate that cultured NPCs cluster together in PCA analysis while primary NPCs segregate into early (E11.5 to E13.5) and later (E16.5, P1) NPC groups. Interestingly, cultured NPCs are close to early NPCs in both PC1 and PC2 axes, suggesting that cultured NPCs are maintained in state close to early NPCs. The close cluster of P20 and P80 NPCs show the robustness of our culture condition in maintaining stable self-renewal state of NPCs. Conclusions: Our study represents the first analysis comparing the long-term cultured NPC lines we geneated with primary NPCs, with biologic replicates, generated by RNA-seq technology. The optimized data analysis workflows reported here should provide a framework for comparative investigations of expression profiles. Our results show that NGS offers a comprehensive and more accurate quantitative and qualitative evaluation of mRNA content within a cell or tissue. We conclude that RNA-seq based transcriptome characterization would expedite genetic network analyses and permit the dissection of complex biologic functions. Overall design: mRNA profiles were generated by deep sequencing in duplicate from E11.5, E12.5, E13.5, E16.5 and P1 primary NPCs, and from long-term cultured NPCs derived from E11.5, E13.5, E16.5 and P1 (Passage 20 and Passage 80 for each cell line)
3D Culture Supports Long-Term Expansion of Mouse and Human Nephrogenic Progenitors.
Specimen part, Cell line, Subject
View SamplesThis dataset describe the transcriptomic profiling of adult brain, gonades (testis and ovaries) of adult zebrafish exposed to 20µg/L of depleted uranium for 10 days. The progeny of the exposed fishes were also analysed at two-cells stage and 96 hours post fertilization Overall design: Biological samples (adult dissected tissues and whole embryos and larvae) were tested by RNASeq in duplicates
Whole transcriptome data of zebrafish exposed to chronic dose of depleted uranium.
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View SamplesThe anterior pituitary-specific transcription factor POU1F1 (also called PIT-1) was initially identified and cloned as a transactivator of PRL, GH and TSH subunit genes. Different studies indicated that POU1F1 could also have other functions in these cells. The identification of new targets of this factor could be useful to obtain a better understanding of these functions.
Research resource: A genome-wide study identifies potential new target genes for POU1F1.
Specimen part
View SamplesThe proper balance of excitatory and inhibitory neurons is crucial to normal processing of somatosensory information in the dorsal spinal cord. Two neural basic helix-loop-helix transcription factors, Ascl1 and Ptf1a, are essential for generating the correct number and sub-type of neurons in multiple regions of the nervous system. Â In the dorsal spinal cord, Ascl1 and Ptf1a have contrasting functions in specifying inhibitory versus excitatory neurons. To understand how Ascl1 and Ptf1a function in these processes, we identified their direct transcriptional targets genome-wide in the embryonic mouse neural tube using ChIP-Seq and RNA-Seq. We show that Ascl1 and Ptf1a regulate the specification of excitatory and inhibitory neurons in the dorsal spinal cord through direct regulation of distinct homeodomain transcription factors known for their function in neuronal sub-type specification. Besides their roles in regulating these homeodomain factors, Ascl1 and Ptf1a each function differently during neuronal development with Ascl1 directly regulating genes with roles in several steps of the neurogenic program including, Notch signaling, neuronal differentiation, axon guidance, and synapse formation. In contrast, Ptf1a directly regulates genes encoding components of the neurotransmitter machinery in inhibitory neurons, and other later aspects of neural development distinct from those regulated by Ascl1. Moreover, Ptf1a represses the excitatory neuronal fate by directly repressing several targets of Ascl1. Examination of the Ascl1 and Ptf1a bound sequences shows they are enriched for a common E-Box with a GC core and with additional motifs used by Sox, Rfx, Pou, and Homeodomain factors. Ptf1a bound sequences are uniquely enriched in an E-Box with a GA/TC core and in the binding motif for its co-factor Rbpj, providing two keys to specificity of Ptf1a binding. The direct transcriptional targets identified for Ascl1 and Ptf1a provide a molecular understanding for how they function in neuronal development, particularly as key regulators of homeodomain transcription factors required for neuronal sub-type specification. Overall design: Examination of gene expression in Ascl1 and Ptf1a lineage cells in the developing neural tube.
A transcription factor network specifying inhibitory versus excitatory neurons in the dorsal spinal cord.
No sample metadata fields
View SamplesThe acute response four hours after a fat load of extra virgin olive oil was investigated using DNA microarrays. Hepatic gene expression was analysed in Wistar Rats.
Postprandial transcriptome associated with virgin olive oil intake in rat liver.
Sex, Age, Specimen part
View SamplesThis study supports an active role for PLZF and RAR-PLZF in leukemogenesis, identifies upregulation of CRABPI as a novel mechanism contributing to retinoid resistance and reveals the ability of the reciprocal fusion gene products to mediate distinct
RARalpha-PLZF overcomes PLZF-mediated repression of CRABPI, contributing to retinoid resistance in t(11;17) acute promyelocytic leukemia.
No sample metadata fields
View SamplesECRG4 is a promising tumor suppressor gene (TSG) recently identified in esophageal carcinoma. Its expression and prognostic value have never been explored in breast cancer. Using DNA microarray, we examined ECRG4 mRNA expression in 353 invasive breast cancer samples. A meta-analysis was performed on a large public retrospective gene expression dataset (n=1,387) to analyze correlation between ECRG4 expression and histo-clinical features including survival.
Down-regulation of ECRG4, a candidate tumor suppressor gene, in human breast cancer.
Age, Specimen part
View SamplesDifferentiation of human pluripotent stem cells toward definitive endoderm (DE) is the critical first step for generating cells comprising organs such as the gut, liver, pancreas and lung. This in-vitro differentiation process generates a heterogeneous population with a proportion of cells failing to differentiate properly and maintaining expression of pluripotency factors such as Oct4. RNA-sequencing of single cells collected at four time points during a 4-day DE differentiation identified high expression of metallothionein genes in the residual Oct4-positive cells that failed to differentiate to DE. Using X-ray fluorescence microscopy and multi-isotope mass spectrometry, we discovered that high intracellular zinc level corresponds with persistent Oct4 expression and failure to differentiate. We further show that differentiation-arrested phenotype is inversely correlated with zinc concentration in the differentiation media. This study improves our understanding of in-vitro DE differentiation and provides actionable options to improve DE differentiation efficiency. Overall design: RNA-sequencing of 329 single cells collected at four time points during a 4-day DE differentiation to identify mechanisms leading to cellular heterogeneity during differentiation
Single-cell RNA sequencing reveals metallothionein heterogeneity during hESC differentiation to definitive endoderm.
Specimen part, Subject, Time
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