1,594 results match your criteria: "École Normale Supérieure PSL Research University[Affiliation]"

Selection can favor a recombination landscape that limits polygenic adaptation.

Mol Biol Evol

January 2025

Institut de Biologie, École Normale Supérieure, CNRS UMR 8197, Inserm U1024, PSL Research University, Paris, F-75005, France.

Modifiers of recombination rates have been described but the selective pressures acting on them and their effect on adaptation to novel environments remain unclear. We performed experimental evolution in the nematode Caenorhabditis elegans using alternative rec-1 alleles modifying the position of meiotic crossovers along chromosomes without detectable direct fitness effects. We show that adaptation to a novel environment is impaired by the allele that decreases recombination rates in the genomic regions containing fitness variation.

View Article and Find Full Text PDF

Reinforcement Learning Optimization of the Charging of a Dicke Quantum Battery.

Phys Rev Lett

December 2024

Freie Universität Berlin, Department of Mathematics and Computer Science, Arnimallee 6, 14195 Berlin, Germany.

Quantum batteries are energy-storing devices, governed by quantum mechanics, that promise high charging performance thanks to collective effects. Because of its experimental feasibility, the Dicke battery-which comprises N two-level systems coupled to a common photon mode-is one of the most promising designs for quantum batteries. However, the chaotic nature of the model severely hinders the extractable energy (ergotropy).

View Article and Find Full Text PDF

Cyclin switch tailors a cell cycle variant to orchestrate multiciliogenesis.

Cell Rep

December 2024

Institut de Biologie de l'ENS (IBENS), CNRS, INSERM, École Normale Supérieure, PSL Research University, Paris, France. Electronic address:

Meiosis, endoreplication, and asynthetic fissions are variations of the canonical cell cycle where either replication or mitotic divisions are muted. Here, we identify a cell cycle variantconserved across organs and mammals, where both replication and mitosis are muted, and that orchestrates the differentiation of post-mitotic progenitors into multiciliated cells (MCCs). MCC progenitors reactivate most of the cell cycle transcriptional program but replace the temporal expression of cyclins E2 and A2 with non-canonical cyclins O and A1.

View Article and Find Full Text PDF

Cyclin O controls entry into the cell-cycle variant required for multiciliated cell differentiation.

Cell Rep

December 2024

Institut de Biologie de l'ENS (IBENS), CNRS, INSERM, Ecole Normale Supérieure, PSL Research University, Paris, France. Electronic address:

Multiciliated cells (MCCs) ensure fluid circulation in various organs. Their differentiation is marked by the amplification of cilia-nucleating centrioles, driven by a genuine cell-cycle variant, which is characterized by wave-like expression of canonical and non-canonical cyclins such as Cyclin O (CCNO). Patients with CCNO mutations exhibit a subtype of primary ciliary dyskinesia called reduced generation of motile cilia (RGMC).

View Article and Find Full Text PDF

Networks of excitatory and inhibitory (EI) neurons form a canonical circuit in the brain. Seminal theoretical results on dynamics of such networks are based on the assumption that synaptic strengths depend on the type of neurons they connect, but are otherwise statistically independent. Recent synaptic physiology datasets however highlight the prominence of specific connectivity patterns that go well beyond what is expected from independent connections.

View Article and Find Full Text PDF

Nuclear magnetic resonance (NMR) spans diverse fields from biology to quantum science. Employing NMR on a floating object could unveil novel possibilities beyond conventional operational paradigms. Here, we observe NMR within a levitating microdiamond using the nuclear spins of nitrogen-14 atoms.

View Article and Find Full Text PDF

Cortical signals have been shown to track acoustic and linguistic properties of continuous speech. This phenomenon has been measured in both children and adults, reflecting speech understanding by adults as well as cognitive functions such as attention and prediction. Furthermore, atypical low-frequency cortical tracking of speech is found in children with phonological difficulties (developmental dyslexia).

View Article and Find Full Text PDF

Immune digital twins for complex human pathologies: applications, limitations, and challenges.

NPJ Syst Biol Appl

November 2024

Biocomplexity Institute and Department of Intelligent Systems Engineering, Indiana University, Bloomington, Indiana, 47408, USA.

Digital twins represent a key technology for precision health. Medical digital twins consist of computational models that represent the health state of individual patients over time, enabling optimal therapeutics and forecasting patient prognosis. Many health conditions involve the immune system, so it is crucial to include its key features when designing medical digital twins.

View Article and Find Full Text PDF

Genetically encoded voltage indicators (GEVIs) allow optical recording of membrane potential from targeted cells . However, red GEVIs that are compatible with two-photon microscopy and that can be multiplexed with green reporters like GCaMP, are currently lacking. To address this gap, we explored diverse rhodopsin proteins as GEVIs and engineered a novel GEVI, 2Photron, based on a rhodopsin from the green algae .

View Article and Find Full Text PDF

Aligned and oblique dynamics in recurrent neural networks.

Elife

November 2024

Rappaport Faculty of Medicine and Network Biology Research Laboratories, Technion - Israel Institute of Technology, Haifa, Israel.

The relation between neural activity and behaviorally relevant variables is at the heart of neuroscience research. When strong, this relation is termed a neural representation. There is increasing evidence, however, for partial dissociations between activity in an area and relevant external variables.

View Article and Find Full Text PDF

Label-Free Optical Transmission Tomography for Direct Mycological Examination and Monitoring of Intracellular Dynamics.

J Fungi (Basel)

October 2024

Lipness Team, Translational Research Center in Molecular Medicine- INSERM Joint Research Unit (CTM-UMR1231), University of Burgundy, 21000 Dijon, France.

Live-cell imaging generally requires pretreatment with fluorophores to either monitor cellular functions or the dynamics of intracellular processes and structures. We have recently introduced full-field optical coherence tomography for the label-free live-cell imaging of fungi with potential clinical applications for the diagnosis of invasive fungal mold infections. While both the spatial resolution and technical set up of this technology are more likely designed for the histopathological analysis of tissue biopsies, there is to our knowledge no previous work reporting the use of a light interference-based optical technique for direct mycological examination and monitoring of intracellular processes.

View Article and Find Full Text PDF
Article Synopsis
  • Statistical physics and dynamical systems theory are essential for understanding high-impact geophysical events, like temperature extremes and cyclones, which arise from deviations in typical geophysical system behaviors.
  • Traditional statistical techniques can predict the likelihood of these events but struggle to connect them to the underlying physics of anomalous geophysical regimes.
  • The paper discusses this gap in knowledge, highlighting challenges and proposing new approaches, particularly stochastic methods, to improve our understanding of extreme geophysical phenomena.
View Article and Find Full Text PDF

Ocean mesoscale eddies, with km size, present in energetic regions of the global ocean, are known to impact local and remote atmospheric weather. The impact of eddies in the Mediterranean Sea on the local weather, however, remains largely unknown. Here, we study this impact during an extreme weather event observed over Israel on January , 2020, resulting in heavy rains and floods.

View Article and Find Full Text PDF

Partial awareness during voluntary endogenous decision.

Conscious Cogn

October 2024

Brain and Consciousness Group (ENS, CNRS), Département d'Études Cognitives, École Normale Supérieure-PSL Research University, Paris, France.

Despite our feeling of control over decisions, our ability to consciously access choices before execution remains debated. Recent research reveals prospective access to intention to act, allowing potential vetoes of impending decisions. However, whether the content of impending decision can be accessed remain debated.

View Article and Find Full Text PDF

Synaptic neoteny of human cortical neurons requires species-specific balancing of SRGAP2-SYNGAP1 cross-inhibition.

Neuron

November 2024

VIB-KULeuven Center for Brain & Disease Research, 3000 Leuven, Belgium; Department of Neurosciences, Leuven Brain Institute, KUL, 3000 Leuven, Belgium; Université Libre de Bruxelles (ULB), Institute for Interdisciplinary Research (IRIBHM), 1070 Brussels, Belgium. Electronic address:

Human-specific (HS) genes have been implicated in brain evolution, but their impact on human neuron development and diseases remains unclear. Here, we study SRGAP2B/C, two HS gene duplications of the ancestral synaptic gene SRGAP2A, in human cortical pyramidal neurons (CPNs) xenotransplanted in the mouse cortex. Downregulation of SRGAP2B/C in human CPNs led to strongly accelerated synaptic development, indicating their requirement for the neoteny that distinguishes human synaptogenesis.

View Article and Find Full Text PDF

CTNND2 moderates the pace of synaptic maturation and links human evolution to synaptic neoteny.

Cell Rep

October 2024

Institut de Biologie de l'ENS (IBENS), Ecole Normale Supérieure, CNRS, INSERM, PSL Research University, 75005 Paris, France. Electronic address:

Human-specific genes are potential drivers of brain evolution. Among them, SRGAP2C has contributed to the emergence of features characterizing human cortical synapses, including their extended period of maturation. SRGAP2C inhibits its ancestral copy, the postsynaptic protein SRGAP2A, but the synaptic molecular pathways differentially regulated in humans by SRGAP2 proteins remain largely unknown.

View Article and Find Full Text PDF

Dimensional models of early life adversity highlight the distinct roles of deprivation and threat in shaping neurocognitive development and mental health. However, relatively little is known about the role of unpredictability within each dimension. We estimated both the average levels of, and the temporal unpredictability of deprivation and threat exposure during adolescence in a high-risk, longitudinal sample of 1354 youth (Pathways to Desistance study).

View Article and Find Full Text PDF

Retrotransposon-driven environmental regulation of FLC leads to adaptive response to herbicide.

Nat Plants

November 2024

Institute of Plant Sciences Paris-Saclay (IPS2), Centre National de la Recherche Scientifique, Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement, Université Evry, Université Paris-Saclay, Gif sur Yvette, France.

The mobilization of transposable elements is a potent source of mutations. In plants, several stransposable elements respond to external cues, fuelling the hypothesis that natural transposition can create environmentally sensitive alleles for adaptation. Here we report on the detailed characterization of a retrotransposon insertion within the first intron of the Arabidopsis floral-repressor gene FLOWERING LOCUS C (FLC) and the discovery of its role for adaptation.

View Article and Find Full Text PDF

Structure of the Nmd4-Upf1 complex supports conservation of the nonsense-mediated mRNA decay pathway between yeast and humans.

PLoS Biol

September 2024

Laboratoire de Biologie Structurale de la Cellule (BIOC), CNRS, Ecole polytechnique, Institut Polytechnique de Paris, Palaiseau, France.

Article Synopsis
  • The NMD pathway helps cells get rid of faulty messenger RNAs (mRNAs) that could cause problems by stopping too early.
  • Researchers studied a protein called Upf1 in yeast and found that it works with another protein called Nmd4 to help this decay process.
  • The study showed that important parts of these proteins are similar in different organisms, suggesting that the NMD process is mostly the same across many living things.
View Article and Find Full Text PDF

RNA degradation triggered by decapping is largely independent of initial deadenylation.

EMBO J

December 2024

Institut Pasteur, Université Paris Cité, CNRS UMR3525, Genetics of Macromolecular Interactions, F-75015, Paris, France.

RNA stability, important for eukaryotic gene expression, is thought to depend on deadenylation rates, with shortened poly(A) tails triggering decapping and 5' to 3' degradation. In contrast to this view, recent large-scale studies indicate that the most unstable mRNAs have, on average, long poly(A) tails. To clarify the role of deadenylation in mRNA decay, we first modeled mRNA poly(A) tail kinetics and mRNA stability in yeast.

View Article and Find Full Text PDF

Supervised deep learning approaches can artificially increase the resolution of microscopy images by learning a mapping between two image resolutions or modalities. However, such methods often require a large set of hard-to-get low-res/high-res image pairs and produce synthetic images with a moderate increase in resolution. Conversely, recent methods based on generative adversarial network (GAN) latent search offered a drastic increase in resolution without the need of paired images.

View Article and Find Full Text PDF

A fast and responsive voltage indicator with enhanced sensitivity for unitary synaptic events.

Neuron

November 2024

Department of Bioengineering, Stanford University, Stanford, CA 94305, USA; Department of Neurobiology, Stanford University, Stanford, CA 94305, USA. Electronic address:

Article Synopsis
  • Researchers developed a new genetically encoded voltage indicator (GEVI) called ASAP5, which offers improved detection of excitatory postsynaptic potentials (EPSPs) and action potentials (APs) with better signal quality compared to previous indicators.
  • ASAP5 was able to detect both spiking and subthreshold neuronal activities in real-time, showing its effectiveness in both animal models and cultured human neurons, even capturing small EPSPs of about 1-mV.
  • The study revealed that EPSP amplitudes decrease as they move away from the source, with further implications for using voltage imaging in studying neuronal dysfunction related to diseases, including those affecting human neurons.
View Article and Find Full Text PDF
Article Synopsis
  • The human immune system continues to develop for several years after birth, affecting how young children respond to infections, such as SARS-CoV-2.
  • Researchers studied T cell responses in children and adults before, during, and after SARS-CoV-2 infection, revealing that younger children (under 5) had a weaker CD4 T cell response compared to older children and adults with mild disease.
  • Following infection, preschool-age children produced similar neutralizing antibodies to adults but had different T cell characteristics and fewer memory B cells, indicating a gradual maturation of their adaptive immune responses.
View Article and Find Full Text PDF

During preimplantation development, mouse embryos form a fluid-filled lumen. Pressurized fluid fractures cell-cell contacts and accumulates into pockets, which coarsen into a single lumen. How the embryo controls intercellular fluid movement during coarsening is unknown.

View Article and Find Full Text PDF

Molecular mechanisms of the specialization of human synapses in the neocortex.

Curr Opin Genet Dev

December 2024

Institut de Biologie de l'ENS (IBENS), Ecole Normale Supérieure, CNRS, INSERM, PSL Research University, 75005 Paris, France. Electronic address:

Synapses of the neocortex specialized during human evolution to develop over extended timescales, process vast amounts of information and increase connectivity, which is thought to underlie our advanced social and cognitive abilities. These features reflect species-specific regulations of neuron and synapse cell biology. However, despite growing understanding of the human genome and the brain transcriptome at the single-cell level, linking human-specific genetic changes to the specialization of human synapses has remained experimentally challenging.

View Article and Find Full Text PDF