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Sanchez, N.

Publications and source records attributed to Sanchez, N..

At least 19 recordsLinked to original sources
bioRxiv2026

The Salmonella effector SspH2 disrupts F-actin cytoskeletal organization to inhibit macrophage migration

The facultative intracellular pathogen Salmonella enterica serovar Typhimurium (S. Typhimurium) causes gastroenteritis in humans and persistent infections in animals, enabling widespread environmental reservoirs. Intracellular survival of S. Typhimurium depends on a suite of type III secretion system effectors encoded within Salmonella Pathogenicity Island 2 (SPI-2), many of which also impair host cell migration. Among these, SspH2 is a novel E3 ubiquitin ligase (NEL) effector, but how it inhibits host cell movement has remained unclear. By using a combination of time-lapse microscopy and wound-healing assays, we show that SspH2 is required for S. Typhimurium to fully suppress migration of macrophage-like RAW264.7 cells and that conditional expression of SspH2 alone is sufficient to restrict their movement. SspH2 expression led to a marked reduction in F-actin and fewer cells containing higher-order F-actin structures, indicating cytoskeletal remodeling. In contrast, the catalytically inactive mutant SspH2C580A had no effect, demonstrating that E3 ligase activity is essential for these phenotypes. Knockdown of the host cytoskeletal factor vinculin, a core component of podosomes and focal adhesions, mimicked SspH2's effect on cell migration. When vinculin expression was reduced, SspH2 did not further inhibit migration, suggesting that SspH2 requires vinculin-associated F-actin-rich structures to block cell migration. These findings reveal a new pathway by which S. Typhimurium limits host cell movement, potentially enhancing immune evasion and fitness within the host.

microbiology↗
bioRxiv2026

"Double-dipping" in testing for phenotypic differences with scRNA-Seq

For the purpose of differential expression (DE) analysis in single-cell RNA-sequencing (scRNA-Seq), phenotype differences between samples are often tested within specific cell types. Cell types are regularly imputed by clustering the same gene expression data which is later used for phenotype testing. This creates the potential for a "double-dipping" or post-selection inference problem resulting in inflated rates of false discoveries. While this selection bias is known to inflate significance in cell-type marker identification, its effect on sample-level phenotype testing, e.g. in patient cohorts, has never been explored despite the growing preponderance of this type of analysis. To address this, we perform an extensive simulation study and demonstrate that naive clustering on uncorrected embeddings can severely inflate the False Discovery Rate (FDR) in the presence of strong phenotypic differences. However, we further show that applying batch-correction methods to remove phenotypic effects prior to clustering resolves the FDR inflation with no obvious loss of power. Finally, we provide measures of phenotypic imbalance that can be applied to real datasets which closely track the false discovery proportion and thus can be used to as part of data exploration to gauge the risk of post-selection inflation of p-values in a particular dataset.

bioinformatics↗
bioRxiv2026

Post-selection inference in testing for phenotypic differences with scRNA-Seq

For the purpose of differential expression (DE) analysis in single-cell RNA-sequencing (scRNA-Seq), phenotype differences between samples are often tested within specific cell types. Cell types are regularly imputed by clustering the same gene expression data which is later used for phenotype testing. This creates the potential for a "double-dipping" or post-selection inference problem resulting in inflated rates of false discoveries. While this selection bias is known to inflate significance in cell-type marker identification, its effect on sample-level phenotype testing, e.g. in patient cohorts, has never been explored despite the growing preponderance of this type of analysis. To address this, we perform an extensive simulation study and demonstrate that naive clustering on uncorrected embeddings can severely inflate the False Discovery Rate (FDR) in the presence of strong phenotypic differences. However, we further show that applying batch-correction methods to remove phenotypic effects prior to clustering resolves the FDR inflation with no obvious loss of power. Finally, we provide measures of phenotypic imbalance that can be applied to real datasets which closely track the false discovery proportion and thus can be used to as part of data exploration to gauge the risk of post-selection inflation of p-values in a particular dataset.

bioinformatics↗
bioRxiv2026

Argentina Explores Its Bathyal and Abyssal Zone for the First Time Using an ROV: New Biodiversity Discoveries and Unprecedented Public Engagement

Between July 23 and August 12, 2025, members of the scientific group Grupo de Estudios del Mar Profundo de Argentina (GEMPA) and collaborators conducted the Talud Continental IV expedition in the Mar del Plata Canyon. The expedition was conducted aboard the R/V Falkor (too) in partnership with Schmidt Ocean Institute (SOI), marking the first deployment of a Remotely Operated Vehicle (ROV) in Argentinean bathyal and abyssal waters. The Mar del Plata Canyon was explored in 2012 and 2013 by CONICET researchers using bottom trawls aboard the R/V Puerto Deseado (CONICET, Argentina). This new expedition combined high-definition video surveys, acoustic seafloor mapping, and physicochemical water-column characterization, with in situ sensing and sampling of fauna (animal specimens, zooplankton, and environmental DNA), water, sediments, and rock to characterize biodiversity and habitats between 880 and 3900 m. The expedition revealed extensive Bathelia cold-water coral reefs, soft-coral gardens, and more than 40 species suspected to be new to science, six of which have already been formally described. Anthropogenic debris, including plastics and fishing gear, was recorded at multiple stations, reaching even the deepest sites, underscoring the extent of human influence on these environments. The Talud Continental IV expedition was successful both scientifically and in promoting deep-ocean literacy and engagement, with broad outreach conducted through SOIs outreach and community engagement programs. The Ship-to-Shore program connected scientists on board with students and educators through live interactive sessions, engaging over 900 students from 19 institutions across Argentina and the United States. The live ROV divestreams, broadcast through SOIs YouTube and Twitch platforms, reached record levels of public engagement, with [~]19 million total views by July 23rd. The national and international press responded with extensive coverage and interview requests, resulting in over 3,900 international stories. Scientists continued to engage with the public after the expedition through talks at schools and public institutions. The expeditions achievements promise to usher in a new era of scientific discovery in the Southwestern Atlantic and underscore the value of integrating exploration, conservation, and outreach to inspire wonder and curiosity about the deep-sea in society. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=179 SRC="FIGDIR/small/726651v3_ufig1.gif" ALT="Figure 1"> View larger version (138K): org.highwire.dtl.DTLVardef@1457548org.highwire.dtl.DTLVardef@116f19aorg.highwire.dtl.DTLVardef@14fbb26org.highwire.dtl.DTLVardef@187c3a4_HPS_FORMAT_FIGEXP M_FIG C_FIG

ecology↗
bioRxiv2025

Urbanisation reshapes community assembly differently across coastal beach and dune habitats

Urbanisation can reduce biodiversity through environmental filtering, but its effects may differ among neighbouring habitats within ecotones. Beach-dune systems provide a useful test because strong environmental gradients occur over short distances and overlap with gradients in human pressure. We collected 660 sediment samples from 55 transects along the Dutch North Sea coast, covering established dunes, incipient dunes, the upper intertidal zone, and the lower intertidal zone. Using environmental DNA metabarcoding and habitat-specific joint species distribution models, we tested how distance-to-city was associated with community composition, operational taxonomic unit (OTU) richness, and OTU-level occurrence. We found compositional differentiation along the urban-proximity gradient in both dune habitats, particularly in incipient dunes, but not in the intertidal habitats. Across all habitats, communities far from cities were more similar to one another than communities near cities, indicating greater among-site compositional variation near urban areas. OTU richness and mean OTU occurrence probabilities increased with distance-to-city in the lower intertidal, upper intertidal, and established dunes. Incipient dunes showed no clear richness gradient or directional OTU-level response despite the strong compositional turnover, suggesting that the main response was community replacement rather than loss of OTUs. Overall, habitat position within the beach-dune ecotone influenced whether biodiversity responses to urban proximity led to directional filtering, compositional turnover, or increased community heterogeneity. Our findings show that biodiversity and impact assessments based on a single habitat may miss important ecological change in coastal habitats.

ecology↗
bioRxiv2024

Parental rejection is associated with intergenerational inheritance of reduced survival, altered behaviours and miRNAs in Owl Monkeys

Parental rejection in captive primates represents severe early-life stress, yet intergenerational effects remain poorly characterised. We investigated spontaneous rejection in owl monkeys (Aotus nancymaae) across two generations using demographic records (n=1,372), behavioural observations (n=65), and blood miRNA profiling (n=47). Rejected individuals showed 51% reduced lifespan, decreased probability of reaching reproductive age, and increased morbidity throughout life. Critically, well-reared offspring of rejected parents exhibited similar reductions in survival to reproductive age and lifespan. Rejected adults displayed heightened fearfulness and aggression with reduced paternal care; offspring showed decreased locomotion and altered stress responses. Blood miRNA analysis revealed significant upregulation of mml-miR-30a-5p in female offspring-a miRNA associated with early-life stress and behavioural disorders in humans. These findings demonstrate intergenerational transmission of rejection effects on fitness and behaviour, with preliminary evidence suggesting epigenetic mechanisms are associated with this transmission, though multiple pathways likely operate.

animal behavior and cognition↗
bioRxiv2024

Identification of distinct subtypes of post-stroke and neurotypical gait behaviors using neural network analysis of kinematic time series data

BackgroundHeterogeneous types of gait impairment are common post-stroke. Studies used supervised and unsupervised machine learning on discrete biomechanical features to summarize the gait cycle and identify common patterns of gait behaviors. However, discrete features cannot account for temporal variations that occur during gait. Here, we propose a novel machine-learning pipeline to identify subgroups of gait behaviors post-stroke using kinematic time series data. MethodsWe analyzed ankle and knee kinematic data during treadmill walking data in 39 individuals post- stroke and 28 neurotypical controls. The data were first input into a supervised dual-stage Convolutional Neural Network-Temporal Convolutional Network, trained to extract temporal and spatial gait features. Then, we used these features to find clusters of different gait behaviors using unsupervised time series k-means. We repeated the clustering process using 10,000 bootstrap training data samples and a Gaussian Mixture Model to identify stable clusters representative of our dataset. Finally, we assessed the kinematic differences between the identified clusters using 1D statistical parametric mapping ANOVA. We then compared gait spatiotemporal and clinical characteristics between clusters using one-way ANOVA. ResultsWe obtained five clusters: two clusters of neurotypical individuals (C1 and C2) and three clusters of individuals post-stroke (S1, S2, S3). C1 had kinematics that resembled the normative gait pattern. Individuals in C2 had a shorter stride time than C1. Individuals in S1 had mild impairment and walked with increased bilateral knee flexion during the loading response. Individuals in S2 had moderate impairment, were the slowest among the clusters, took shorter steps, had increased knee flexion during stance bilaterally and reduced paretic knee flexion during swing. Individuals in S3 had mild impairment, asymmetric swing time, had increased ankle abduction during the gait cycle and reduced dorsiflexion bilaterally during loading response and stance. Every individual was assigned to a cluster with a cluster membership likelihood above 93%. ConclusionsOur results indicate that joint kinematics in individuals post-stroke are distinct from controls, even in those individuals with mild impairment. The three subgroups post-stroke showed distinct kinematic impairments during specific phases in the gait cycle, providing additional information to clinicians for gait retraining interventions.

bioengineering↗
bioRxiv2024

Accurate Predictions of Phase Separating Proteins at Single Amino Acid Resolution

Liquid-liquid phase separation (LLPS) is a molecular mechanism that leads to the formation of membraneless organelles inside the cell. Despite recent advances in the experimental probing and computational prediction of proteins involved in this process, the identification of the protein regions driving LLPS and the prediction of the effect of mutations on LLPS are lagging behind. Here, we introduce catGRANULE 2.0 ROBOT (R - Ribonucleoprotein, O - Organization, in B - Biocondensates, O - Organelle, T - Types), an advanced algorithm for predicting protein LLPS at single amino acid resolution. Integrating physico-chemical properties of the proteins and structural features derived from AlphaFold models, catGRANULE 2.0 ROBOT significantly surpasses traditional sequence-based and state-of-the-art structure-based methods in performance, achieving an Area Under the Receiver Operating Characteristic Curve (AUROC) of 0.76 or higher. We present a comprehensive evaluation of the algorithm across multiple organisms and cellular components, demonstrating its effectiveness in predicting LLPS propensities at the single amino acid level and the impacts of mutations on LLPS. Our results are robustly supported by experimental validations, including immunofluorescence microscopy images from the Human Protein Atlas. catGRANULE 2.0 ROBOTs potential in protein design and mutation control can improve our understanding of proteins propensity to form subcellular compartments and help develop strategies to influence biological processes through LLPS. catGRANULE 2.0 ROBOT is freely available at https://tools.tartaglialab. com/catgranule2.

biochemistry↗
bioRxiv2024

Perception of task duration influences metabolic cost during split-belt adaptation and biomechanics during both adaptation and post-adaptation

Studies of locomotor adaptation have shown that adaptation can occur in short bouts and can continue for long bouts or across days. Information about task duration might influence the adaptation of gait features, given that task duration influences the time available to explore and adapt the aspects of gait that reduce energy cost. We hypothesized that information about task duration influences adaptation to split-belt walking based on two competing mechanisms: individuals anticipating a prolonged adaptation period may either (1) extend exploration of energetically suboptimal gait patterns, or (2) adapt toward a more energy-efficient pattern earlier to maintain an energetic reserve to sustain the task longer. We tested three groups: N=19 participants received minute-by-minute updates during a 10-minute adaptation duration (True group), N=19 participants received no updates during a 10-minute adaptation duration and were misled to expect a prolonged 30-minute adaptation duration (False group), and N=14 participants received one update halfway through a 10-minute adaptation duration (Control group). We measured step length asymmetry, leg work, and metabolic cost. Our results partially supported our hypothesis but did not confirm the underlying mechanisms. While step length asymmetry did not differ significantly between groups during adaptation, the True group generated a more effortful gait pattern with a greater increase in metabolic cost (p=0.002) and higher work with the leg on the slow belt (p=0.012). Additionally, the True group showed no association between step length asymmetry and metabolic cost (p=0.203), contrary to the Control (r=-0.55, p=0.043) and False groups (r=-0.51, p=0.027). Finally, we observed that the False group showed greater retention of the split-belt aftereffects than the Control and False groups (p<0.001). Thus, adapted locomotor and energetic patterns are influenced by information about task duration, indicating that Information about task duration should be controlled for, or can be manipulated to elicit different efforts during adaptation.

neuroscience↗
bioRxiv2024

Enhancing metabarcoding efficiency and ecological insights through integrated taxonomy and DNA reference barcoding: a case study on beach meiofauna

Molecular techniques like metabarcoding, while promising for exploring diversity of communities, are often impeded by the lack of reference DNA sequences available for taxonomic annotation. Our study explores the benefits of combining targeted DNA barcoding and morphological taxonomy to improve metabarcoding efficiency, using beach meiofauna as a case study. Beaches are globally important ecosystems and are inhabited by meiofauna, microscopic animals living in the interstitial space between the sand grains, which play a key role in coastal biodiversity and ecosystem dynamics. However, research on meiofauna faces challenges due to limited taxonomic expertise and sparse sampling. We generated 775 new cytochrome c oxidase I DNA barcodes from meiofauna specimens collected along the Netherlands west coast and combined them with the NCBI GenBank database. We analysed alpha and beta diversity in 561 metabarcoding samples from 24 North Sea beaches, a region extensively studied for meiofauna, using both the enriched reference database and the NCBI database without the additional reference barcodes. Our results show a 2.5-fold increase in sequence annotation and a doubling of species-level Operational Taxonomic Units (OTUs) identification when annotating the metabarcoding data with the enhanced database. Additionally, our analyses revealed a bell-shaped curve of OTU richness across the intertidal zone, aligning more closely with morphological analysis patterns, and more defined community dissimilarity patterns between supralittoral and intertidal sites. Our research highlights the importance of expanding molecular reference databases and combining morphological taxonomy with molecular techniques for biodiversity assessments, ultimately improving our understanding of coastal ecosystems.

molecular biology↗
bioRxiv2023

Distribution and dynamics of chromatin states in the C. elegans germ line

Chromatin organization in the C. elegans germ line is tightly regulated and critical for germ cell differentiation. While certain germline epigenetic regulatory mechanisms have been identified, how they influence chromatin structure and ultimately gene expression remain unclear, in part because most genomic studies have focused on data collected from whole worms. We therefore analyzed publicly available histone modification and chromatin accessibility data from isolated undifferentiated germ nuclei to define chromatin states. We then correlated these states with overall transcript abundance, spatio-temporal expression patterns, and the function of small RNA pathways. Because the essential role of the germ line is to transmit genetic information to the next generation and establish gene expression in the early embryo, we compared epigenetic and transcriptomic profiles from undifferentiated germ cells, oocytes, and embryos to define the epigenetic changes during this developmental transition. The active histone modification H3K4me3 exhibits particularly dynamic remodeling as germ cells differentiate into oocytes. Our results highlight the dynamism of the chromatin landscape in germ cells, and provide a resource for future investigation into epigenetic regulatory mechanisms.

genomics↗
bioRxiv2023

The Upstream Sequence Transcription Complex Dictates Nucleosome Positioning and Promoter Accessibility at piRNA Genes in the C. elegans Germ Line

The piRNA pathway is a conserved germline-specific small RNA pathway that ensures genomic integrity and continued fertility. In C. elegans and other nematodes, Type-I piRNA precursor transcripts are expressed from over 10,000 small, independently regulated genes clustered within two discrete domains of 1.5 and 3.5 MB on Chromosome IV. These large clusters likely play a significant role in promoting germline-specific expression of piRNAs, but the underlying mechanisms are unclear. By examining the chromatin environment specifically in isolated germ nuclei, we demonstrate that piRNA clusters are located in closed chromatin, and confirm the enrichment for the inactive histone modification H3K27me3. We further show that the piRNA biogenesis factor USTC (Upstream Sequence Transcription Complex) plays two roles - it promotes a strong association of nucleosomes throughout the piRNA clusters, and it organizes the local nucleosome environment to direct the exposure of individual piRNA genes. Overall, this work reveals new insight into how chromatin state coordinates transcriptional regulation over large genomic domains, which has implications for understanding global genome organization in the germ line.

genomics↗
bioRxiv2023

Multi-site identification and generalization of clusters of walking impairment in individuals with chronic stroke

BackgroundWalking patterns in stroke survivors are highly heterogeneous, which poses a challenge in systematizing treatment prescriptions for walking rehabilitation interventions. ObjectiveWe used bilateral spatiotemporal and force data during walking to create a multi-site research sample to: 1) identify clusters of walking behaviors in people post-stroke and neurotypical controls, and 2) determine the generalizability of these walking clusters across different research sites. We hypothesized that participants post-stroke will have different walking impairments resulting in different clusters of walking behaviors, which are also different from control participants. MethodsWe gathered data from 81 post-stroke participants across four research sites and collected data from 31 control participants. Using sparse K-means clustering, we identified walking clusters based on 17 spatiotemporal and force variables. We analyzed the biomechanical features within each cluster to characterize cluster-specific walking behaviors. We also assessed the generalizability of the clusters using a leave-one-out approach. ResultsWe identified four stroke clusters: a fast and asymmetric cluster, a moderate speed and asymmetric cluster, a slow cluster with frontal plane force asymmetries, and a slow and symmetric cluster. We also identified a moderate speed and symmetric gait cluster composed of controls and participants post-stroke. The moderate speed and asymmetric stroke cluster did not generalize across sites. ConclusionsAlthough post-stroke walking patterns are heterogenous, these patterns can be systematically classified into distinct clusters based on spatiotemporal and force data. Future interventions could target the key features that characterize each cluster to increase the efficacy of interventions to improve mobility in people post-stroke.

neuroscience↗
bioRxiv2022

Habitual weekly exercise affects gait adaptation in healthy young adults

Changing movement patterns in response to environmental perturbations is a critical aspect of gait and is related to reducing the energetic cost of the movement. Exercise improves energetic capacity for submaximal exercise and may affect how people adapt movement to reach an energetic minimum. The purpose of this study was to determine whether self-reported exercise behavior influences gait adaptation in young adults. Young adults who met the optimal volume of exercise according to the Physical Activity Guidelines for Americans (MOVE; n=19) and young adults who did not meet the optimal volume of exercise (notMOVE; n=13) walked on a split-belt treadmill with one belt moving twice the speed of the other belt for 10 minutes. Step length asymmetry (SLA) and mechanical work done by each leg were measured. Nonlinear mixed effects models compared the time course of adaptation between MOVE and notMOVE, and t-tests compared net work at the end of adaptation between MOVE and notMOVE. Compared to notMOVE, MOVE had a faster initial response to the split belt treadmill, and continued to adapt over the duration of split-belt treadmill walking. Young adults who engage in sufficient amounts of exercise responded more quickly to the onset of a perturbation, and throughout the perturbation they continued to explore movement strategies, which might be related to reduction of energetic cost. Our findings provide insights into the multisystem positive effects of exercise, including walking adaptation.

neuroscience↗
bioRxiv2021

Meiofauna is an important, yet neglected, component of biodiversity of Posidonia oceanica

Posidonia oceanica meadows are biodiversity reservoirs and provide many ecosystem services in coastal Mediterranean regions. Marine meiofauna, on the other hand, not only represents a major component of regional marine biodiversity, but also a useful tool to address both theoretical and applied questions in ecology, evolution, and conservation. We review the meiofaunal diversity in the P. oceanica ecosystem combining a literature review and a case study. First, we gathered records of 664 species from 69 published studies as well as unpublished sources, including few species exclusive from this ecosystem. Eighteen of those studies quantified the spatial and temporal changes of species composition, highlighting habitat-specific assemblages that fluctuate following the annual changes experienced by P. oceanica. Hydrodynamics, habitat complexity, and food availability, all three inherently linked to the seagrass phenology, are recognised as the main factors at shaping the complex distribution patterns of meiofauna in the meadows. These drivers have been identified mainly from Copepoda and Nematoda, and depend ultimately on species-specific preferences. Second, we tested the generality of these observations using marine mites as a model group, showing that the same processes might be in place also for other less abundant meiofaunal groups. Overall, our study highlights an outstanding diversity of meiofauna in P. oceanica and shows its potential for future research, not only focused on exploring and describing new species of neglected meiofaunal organisms, but also providing a more complete understanding on the functioning of the iconic Mediterranean ecosystem created by P. oceanica.

ecology↗
bioRxiv2020

Rejection in early life is associated with high and long-lasting stress and higher incidence of infections in owl monkeys

1.BackgroundThe mothers of owl monkeys sometimes reject their new-borns. When this occurs in captive colonies, the rejected infants are manually raised by veterinarians, allowing them to survive. However, maternal rejection can induce chronic stress, which in turn is associated with infectious diseases. Rescued, rejected owl monkeys might experience high rates of stress and infections which go undetected. MethodologyTo test this hypothesis, we evaluated the connection between maternal rejection, stress and infections in owl monkeys (Aotus nancymaae) from the IVITA Center for Conservation and Reproduction of Primates (UNMSM, Peru). Specifically, we compared the stress rates and frequency of infection treatment in juveniles (19-24 months) rejected in the first month of life and controls. To assess stress, we compared cortisol levels in hair using a competitive ELISA and recorded behaviours using cameras. We analysed past medical treatments and medication to compare incidence of infection treatment in subjects. We then studied the correlation between the frequency of infection treatments and cortisol using a linear regression. ResultsRejected owl monkeys showed significantly higher cortisol levels (p=0.0123), a higher incidence of stereotypical behaviour and overeating (pacing p=0.0159; head twirling p=0.0476, eating p=0.0238) compared to controls. Rejected owl monkeys also received significantly more treatment for infections than controls per month lived (p=0.0009). Moreover, infection rates observed in this population were positively although weakly associated with concentration of cortisol in hair (R2=0.307, p=0.0075). ConclusionMaternal rejection in the first month of life is associated with high and long-lasting stress levels and infections in the IVITA owl monkey colony. IVITA owl monkeys will be a useful model for studying the long-term effects of early life stress at the population level.

neuroscience↗
bioRxiv2020

RTP801 Is A Key Modulator For Motor Learning

RTP801/REDD1 is a stress-regulated protein whose upregulation is necessary and sufficient to trigger neuronal death in in vitro and in vivo models of Parkinsons and Huntingtons diseases and is up regulated in compromised neurons in human postmortem brains of both neurodegenerative disorders. Indeed, in both Parkinsons and Huntingtons disease mouse models, RTP801 knockdown alleviates motor-learning deficits. Here, we investigated the physiological role of RTP801 in neuronal plasticity. RTP801 is found in rat, mouse and human synapses. The absence of RTP801 enhanced excitatory synaptic transmission in both neuronal cultures and brain slices from RTP801 knock-out (KO) mice. Indeed, RTP801 KO mice showed improved motor learning, which correlated with lower spine density but increased basal filopodia and mushroom spines in the motor cortex layer V. This paralleled with higher levels of synaptosomal GluA1 and TrkB receptors in homogenates derived from KO mice motor cortex, proteins that are associated with synaptic strengthening. Altogether, these results indicate that RTP801 has an important role modulating neuronal plasticity in motor learning.

neuroscience↗
bioRxiv2020

Habitat differences filter functional diversity of low dispersive microscopic animals

O_LIWhereas the study of patterns of distribution of microscopic animals has long been dominated by the ubiquity paradigm, we are starting to appreciate that microscopic animals are not as widespread as previously thought and that habitat preferences may have a strong role in structuring their patterns of occurrence. However, we still ignore to what extent and through which mechanisms the environment selects for specific communities or traits in microscopic animals. This gap is partly due to the lack of data on the relevant traits of many species, and partly because measuring environmental variables at an appropriate resolution may be problematic. C_LIO_LIWe here overcome both issues by analysing the functional space of marine mite communities living in a sea-grass (Posidonia oceanica) meadow across two habitats: the leaves and the matte. The strictly benthic lifestyle and the conserved morphology of mites allow for unambiguous characterization of their functional traits, while the discrete nature of the two habitats alleviates the uncertainty in their ecological characterization. C_LIO_LIOur results show that habitat filters the distribution of certain traits favouring a higher diversity, dispersion, and evenness of functional traits in the matte than in the leaves. We further observed temporal variations in the functional diversity of communities, potentially following the seasonal renovation and decay of seagrass leaves. However, in spite of the stark ecological differences between the two habitats and across seasons, the filtering effect is partial and affects mostly relative species abundances. C_LIO_LIWe conclude that in other microscopic organisms, habitat filtering might appear even more subtle especially if they are capable of long distance dispersal or occur in ecological systems where environmental variables vary continuously or fluctuate through time. Our study therefore emphasises the need of moving from a merely taxonomical toward a functional view of ecological studies of microscopic organisms if we want to achieve a mechanistic understanding of their habitat and distribution patterns. C_LI Data availability statementRaw data and R script to generate the analyses will be deposited in a public repository upon acceptance.

ecology↗