The field of single-cell omics has transformed our understanding of biological processes and is constantly advancing both experimentally and computationally. One of the most significant developments is the ability to measure the transcriptome of individual cells by single-cell RNA-seq (scRNA-seq), which was pioneered in higher eukaryotes. While yeast has served as a powerful model organism in which to test and develop transcriptomic technologies, the implementation of scRNA-seq has been significantly delayed in this organism, mainly because of technical constraints associated with its intrinsic characteristics, namely the presence of a cell wall, a small cell size and little amounts of RNA.
View Article and Find Full Text PDFIn the nucleus, chromatin is intricately structured into multiple layers of 3D organization important for genome activity. How distinct layers influence each other is not well understood. In particular, the contribution of chromosome pairing to 3D chromatin organization has been largely neglected.
View Article and Find Full Text PDFBackground: Epigenetic programming during development is essential for determining cell lineages, and alterations in this programming contribute to the initiation of embryonal tumour development. In neuroblastoma, neural crest progenitors block their course of natural differentiation into sympathoadrenergic cells, leading to the development of aggressive and metastatic paediatric cancer. Research of the epigenetic regulators responsible for oncogenic epigenomic networks is crucial for developing new epigenetic-based therapies against these tumours.
View Article and Find Full Text PDFLiving organisms are continuously challenged by changes in their environment that can propagate to stresses at the cellular level, such as rapid changes in osmolarity or oxygen tension. To survive these sudden changes, cells have developed stress-responsive mechanisms that tune cellular processes. The response of to osmostress includes a massive reprogramming of gene expression.
View Article and Find Full Text PDFCells have the ability to sense, respond and adapt to environmental fluctuations. Stress causes a massive reorganization of the transcriptional program. Many examples of histone post-translational modifications (PTMs) have been associated with transcriptional activation or repression under steady-state growth conditions.
View Article and Find Full Text PDFIron is an indispensable micronutrient for all eukaryotic organisms due to its participation as a redox cofactor in many metabolic pathways. Iron imbalance leads to the most frequent human nutritional deficiency in the world. Adaptation to iron limitation requires a global reorganization of the cellular metabolism directed to prioritize iron utilization for essential processes.
View Article and Find Full Text PDFDuring development, morphogens provide extracellular cues allowing cells to select a specific fate by inducing complex transcriptional programs. The mating pathway in budding yeast offers simplified settings to understand this process. Pheromone secreted by the mating partner triggers the activity of a MAPK pathway, which results in the expression of hundreds of genes.
View Article and Find Full Text PDFCells trigger massive changes in gene expression upon environmental fluctuations. The Hog1 stress-activated protein kinase (SAPK) is an important regulator of the transcriptional activation program that maximizes cell fitness when yeast cells are exposed to osmostress. Besides being associated with transcription factors bound at target promoters to stimulate transcriptional initiation, activated Hog1 behaves as a transcriptional elongation factor that is selective for stress-responsive genes.
View Article and Find Full Text PDFThe understanding of interaction dynamics in signaling pathways can shed light on pathway architecture and provide insights into targets for intervention. Here, we explored the relevance of kinetic rate constants of a key upstream osmosensor in the yeast high-osmolarity glycerol-mitogen-activated protein kinase (HOG-MAPK) pathway to signaling output responses. We created mutant pairs of the Sln1-Ypd1 complex interface that caused major compensating changes in the association (k) and dissociation (k) rate constants (kinetic perturbations) but only moderate changes in the overall complex affinity (K).
View Article and Find Full Text PDFLiving organisms have evolved protein phosphorylation, a rapid and versatile mechanism that drives signaling and regulates protein function. We report the phosphoproteomes of 18 fungal species and a phylogenetic-based approach to study phosphosite evolution. We observe rapid divergence, with only a small fraction of phosphosites conserved over hundreds of millions of years.
View Article and Find Full Text PDFChromatin remodeling is essential for proper adaptation to extracellular stimuli. The p38-related Hog1 SAPK is an important regulator of transcription that mediates chromatin remodeling upon stress. Hog1 targets the RSC chromatin remodeling complex to stress-responsive genes and rsc deficient cells display reduced induction of gene expression.
View Article and Find Full Text PDFEukaryotic cells have developed sophisticated systems to constantly monitor changes in the extracellular environment and to orchestrate a proper cellular response. To maximize survival, cells delay cell-cycle progression in response to environmental changes. In response to extracellular insults, stress-activated protein kinases (SAPKs) modulate cell-cycle progression and gene expression.
View Article and Find Full Text PDFBackground: There is substantive literature reporting the importance and benefits of music and music therapy programs for older adults, and more specifically for those with dementia. However, few studies have focused on how these programs may contribute to quality of life.
Objectives: Objectives for this exploratory study were: (a) to evaluate the potential effect of group music therapy program participation on the quality of life of older people with mild, moderate, and severe dementia living in a nursing home; (b) to identify and analyze changes in affect and participation that take place during music therapy sessions; and (c) to suggest recommendations and strategies for the design of future music therapy studies with people in various stages of dementias.
Genomic analysis has revealed the existence of a large number of long noncoding RNAs (lncRNAs) with different functions in a variety of organisms, including yeast. Cells display dramatic changes of gene expression upon environmental changes. Upon osmostress, hundreds of stress-responsive genes are induced by the stress-activated protein kinase (SAPK) p38/Hog1.
View Article and Find Full Text PDFThe neuronal long isoform of Fas Apoptotic Inhibitory Molecule (FAIM-L) protects from death receptor (DR)-induced apoptosis, yet its mechanism of protection remains unknown. Here, we show that FAIM-L protects rat neuronal Type II cells from Fas-induced apoptosis. XIAP has previously emerged as a molecular discriminator that is upregulated in Type II and downregulated in Type I apoptotic signaling.
View Article and Find Full Text PDFTNFα can promote either cell survival or cell death. The activation of NF-κB plays a central role in cell survival while its inhibition makes TNFα-triggered cytotoxicity possible. Here, we report that the overexpression of a non-degradable mutant of the inhibitor of NF-κB (super-repressor (SR)-IκBα) sensitizes HeLa cells towards TNFα-induced apoptosis, involving caspases activation and cytocrome C release from the mitochondria.
View Article and Find Full Text PDFProtein ubiquitylation is a key process in the regulation of many cellular processes. The balance between the activity of ubiquitin ligases and that of proteases controls the level of ubiquitylation. In response to extracellular stimuli, stress-activated protein kinases (SAPK) modulate gene expression to maximize cell survival.
View Article and Find Full Text PDFThe purpose of this study was: (a) To evaluate and to compare the impact of three music programs (choir, music appreciation and preventive music therapy sessions) on the quality of life of healthy older adults, and (b) to identify the motivations and the difficulties that seniors encounter when participating in activities of this type, in order to come up with recommendations and strategies for the design of appropriate programs for older adults. A pre-posttest quasi-experimental design without equivalent control group was used in this project. The sample included 83 persons over 65 years of age.
View Article and Find Full Text PDFTwo studies were designed to develop and obtain information about the psychometric properties of a shortened 54-item, Spanish version of Ryff's Scales of Psychological Well-being adapted to older people. In Study 1, 267 older people completed the scales, and data were submitted to a principal components analysis. Then, 22 items were selected and grouped into four components (Self-confidence, Orientation to present, Stress, and Social tension) to form the Simplified Ryff's Well-being Scales.
View Article and Find Full Text PDFFLICE-inhibitory protein (FLIP) is an endogenous inhibitor of the signaling pathway triggered by the activation of death receptors. Here, we reveal a novel biological function for the long form of FLIP (FLIP-L) in neuronal differentiation, which can be dissociated from its antiapoptotic role. We show that FLIP-L is expressed in different regions of the mouse embryonic nervous system.
View Article and Find Full Text PDFIn yeast, environmental stresses provoke sudden and dramatic increases in gene expression at stress-inducible loci. Stress gene transcription is accompanied by the transient eviction of histones from the promoter and the transcribed regions of these genes. We found that mutants defective in subunits of the INO80 complex, as well as in several histone chaperone systems, exhibit extended expression windows that can be correlated with a distinct delay in histone redeposition during adaptation.
View Article and Find Full Text PDFThis study is aimed at exploring daily and desired activity patterns in a sample of older people living in a rural context, as well as at examining the effect of some influential factors and their relationships with life satisfaction. Our sample was made of 216 retired people and was recruited from 12 villages from Catalonia and Valencia with populations of less than 1000 inhabitants. Data were gathered by means of an interview that included daily and ideal activities and life satisfaction (by applying the Life Satisfaction Index).
View Article and Find Full Text PDFUpon activation, tumor necrosis factor alpha (TNF-alpha) receptor can engage apoptotic or survival pathways. Inhibition of macromolecular synthesis is known to sensitize cells to TNF-alpha-induced cell death. It is believed that this sensitization is due to the transcriptional blockade of genes regulated by NF-kappaB.
View Article and Find Full Text PDFDeath receptors (DRs) and their ligands are expressed in developing nervous system. However, neurons are generally resistant to death induction through DRs and rather their activation promotes neuronal outgrowth and branching. These results suppose the existence of DRs antagonists expressed in the nervous system.
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