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Search indexed bioRxiv preprints in genomics, neuroscience, cell biology and bioinformatics. Read source abstracts and check manuscript versions; preprints are not peer reviewed.

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At least 415 records · Page 23Linked to original sources

bioRxiv2026

Transcriptomic and physiological analyses reveal a salinity-induced growth suppression and defense activation in spring barley

Salinity is a major abiotic stress that severely limits plant growth and productivity, causing substantial yield losses. Despite barleys relative tolerance to salinity, the underlying physiological and molecular mechanisms remain incompletely understood. In this study, we employed an integrative approach combining agronomic, physiological, biochemical, and transcriptomic analyses to investigate salinity responses in the spring barley cultivar Giza 134 under both field and lysimeter-based conditions. Salinity stress significantly reduced growth and yield-related traits, with more pronounced effects observed under lysimeter-imposed salinity, reflecting higher stress intensity. These reductions were associated with impaired water status, altered leaf structural traits, and declines in photosynthetic pigment content. In contrast, proline accumulation increased, indicating activation of osmotic adjustment mechanisms. Salinity also disrupted ionic homeostasis, as evidenced by elevated Na+ levels, reduced K+ content, and an increased Na+/K+ ratio. Enhanced lipid peroxidation and elevated catalase and peroxidase activities suggested increased oxidative stress and activation of antioxidant defenses. Transcriptome profiling identified 4,298 differentially expressed genes, including 1,764 upregulated and 2,534 downregulated genes. Functional enrichment analyses revealed upregulation of pathways related to stress adaptation, redox regulation, and metabolic reprogramming, while genes associated with photosynthesis, ribosome biogenesis, and protein synthesis were strongly suppressed. Several novel stress-responsive genes involved in signaling, osmoprotection, antioxidant defense, and central metabolism were highly induced, supported by coordinated enrichment of cis-regulatory motifs in their promoter regions. Together, these findings provide a comprehensive physiological and molecular framework for salinity tolerance in Giza 134 and highlight candidate genes and pathways for breeding salt-resilient cultivars suited to saline-prone environments.

plant biology↗

bioRxiv2026

PhysioMap: an ontology-grounded causal knowledge graph of human physiology

Computational physiology needs representations that connect traits across biological scales while distinguishing causal, constitutive, and mathematical dependencies. We present PhysioMap, an ontology-grounded knowledge base of contextualized physiological traits and precisely defined relation types. A versioned projection maps entailed ontology patterns to a typed causal knowledge graph that constrains quantitative structural causal models. Derivative signs provide a separate qualitative abstraction, which the PhysioMap solver uses to analyze steady-state responses in the presence of feedback. A stratified expert review across all relation types supported most sampled relations and isolated a minority for correction or further investigation. In a rare metabolic disease application, nearly all determinate predictions agreed with the HPO-derived reference before post-hoc review; after the discordant reference directions were excluded, all remaining determinate predictions agreed. Shortest signed paths produced directional errors, particularly on cases for which the PhysioMap solver did not determine a direction, indicating that its abstentions concentrated difficult cases. Abduction usually narrowed the candidate set but often did not identify a unique cause. PhysioMap therefore connects ontology-grounded physiological content to interventional prediction and abduction under incomplete quantitative knowledge. Because PhysioMap curation and the HPO-derived reference may share supporting literature, and because abduction used a closed candidate pool, these analyses do not constitute independent clinical validation.

bioinformatics↗

bioRxiv2026

Attenuating LRRK2 activity ameliorates progerin-induced aging phenotypes in HGPS models and during physiological aging

Hutchinson-Gilford progeria syndrome (HGPS) is an ultra-rare premature aging disorder caused by progerin, a truncated lamin A variant generated by a silent de novo mutation activating a cryptic splice site in LMNA. The resulting morphological, epigenetic, genomic, and proteostasic defects closely recapitulate some hallmarks of cellular aging. Here, we identify the Parkinsons disease-associated kinase LRRK2 as a critical regulator of HGPS pathology and physiological aging. Rab29-mediated LRRK2 hyperactivation exacerbates progerin-induced cellular aging, whereas LRRK2 knockdown or overexpression of its opposing phosphatase, PPM1H, ameliorates progerin-induced defects. Progerin-expressing cells exhibit altered intracellular trafficking, which is regulated by LRRK2 and links diverse aging hallmarks. Consistent with these findings, reducing LRRK2 levels mitigates cellular aging phenotypes in physiologically aged cells, and loss of the C. elegans ortholog lrk-1 preserves aging-associated loss of motility and extends organismal lifespan. Together, our findings establish LRRK2 as a central node in cellular aging and position it as a potential therapeutic target for aging-related defects in both HGPS and physiological aging.

cell biology↗

bioRxiv2026

A platform for automated training of mammalian cell physiology

Controlling cell physiology is difficult, not only because of cells complexity, but also their capacity for real-time adaptation to interventions, leading to challenges such as drug resistance and transgene silencing. Accumulating evidence suggests that this adaptivity resembles classical forms of learning defined in behavioral science. However, a lack of appropriate platforms has led to gaps in our understanding of cells capacity for adaptive problem-solving in physiological and transcriptional space. Here, we present a device, the Cell Trainer, capable of performing a wide variety of automated training experiments on non-neural mammalian cells, using timed drug pulses as the stimulus, and a mobile fluorescence microscope to capture images of responses, across replicate cultures. The Cell Trainer can operate in either an open-loop (feedforward) or closed-loop (feedback-controlled) mode, and our image analysis pipeline can report the behaviors of individual cells throughout each experiment and quantify population heterogeneity. We showcase the ability of the Cell Trainer to execute experimental protocols and perform single-cell analyses in both modes. We first demonstrate with a feedforward experiment in which myoblasts are repeatedly pulsed with dimethyl sulfoxide (DMSO) and their discrete calcium responses are analyzed, revealing sensitization-like dynamics. Next, we demonstrate a feedback control scheme wherein the fluorescence of a pH/voltage reporter in kidney cells is maintained below a threshold level with controlled pulses of acid. To accelerate research in the field of cell training, learning, and memory, we are openly sharing the Cell Trainer schematics and software with the research community. This platform provides a flexible tool for studying how cellular physiological states can be shaped by patterned stimulation and feedback control through approaches that work with the native adaptive competencies of cells.

bioengineering↗

bioRxiv2026

Physiological fatty acid uptake reveals spatial and systemic constraints on nutrient accessibility in vivo

Immune cells rely on exogenous fatty acids (FA) for membrane synthesis, bioenergetics and signalling, yet current approaches cannot accurately quantify physiological FA uptake in vivo. Here, we use cyclopropene-tagged fatty acids (cpFA) that, unlike existing FA-uptake tools, are taken up by physiologically relevant mechanisms. We measure FA uptake at single-cell resolution in vivo and uncover a previously unappreciated distinction between nutrient uptake capacity and nutrient accessibility. Although arachidonic acid exhibits the highest uptake capacity ex vivo across immune populations, it displays limited tissue accessibility in vivo, whereas palmitate is broadly accessible. In vivo nutrient-uptake measurements reveal that tissue architecture shapes nutrient accessibility, with spatial constraints in the spleen and exclusion of circulating FA, but not amino acids, from the thymus. Together, these findings identify nutrient accessibility as a distinct layer of metabolic regulation and reveal that immune-cell metabolism is shaped by spatial and systemic constraints on nutrient access HighlightsO_LINutrient accessibility is a distinct layer of metabolic regulation C_LIO_LIPhysiological FA uptake differs from ex vivo uptake capacity C_LIO_LISpatial and systemic factors govern fatty-acid accessibility C_LIO_LITissue context shapes immune-cell metabolism in vivo C_LI In briefUsing bioorthogonal FA to quantify physiological nutrient uptake in vivo, Wang et al. show that nutrient accessibility is distinct from nutrient uptake capacity. Tissue architecture and systemic FA distribution create spatial constraints on nutrient access, revealing an underappreciated layer of metabolic regulation in immune cells.

immunology↗

bioRxiv2026

Genetic variation in behavioral and physiological responses to copper in Drosophila melanogaster

Anthropogenic copper (Cu) contamination from agriculture, mining, and industrial runoff creates environmental gradients affecting physiology and behavior in wild populations. While Cu toxicity in Drosophila melanogaster is well characterized, it remains unclear whether Cu resistance is one integrated trait or several independently evolving components. Using a subset of recombinant inbred lines (RILs) from the Drosophila Synthetic Population Resource (DSPR), we measured three components of Cu response: feeding avoidance, oviposition avoidance, and physiological tolerance (median lethal time, LT50) under sustained Cu exposure. All three traits showed substantial phenotypic variation among RILs. Feeding and oviposition avoidance were both highly heritable (H 2 ~ 0.88), and RIL identity accounted for 49.5% of the variance in LT50. However, the three traits showed no significant correlation across RILs, indicating distinct genetic architecture. We identified a single male specific quantitative trait locus (QTL) on chromosome 2R that explained 17.7% of the variation in feeding preference; the interval included candidate detoxification genes Jheh1, Jheh2, Jheh3 and sano, the latter of which is associated with olfactory behavior. No significant QTL were detected for oviposition preference, suggesting a highly polygenic structure that may difficult to detect with our limited panel size. Together, these results indicate that Cu resistance in D. melanogaster is genetically modular. Behavioral avoidance during feeding, oviposition, and physiological tolerance are heritable but architecturally distinct components, each with potential to respond to selection independently.

genetics↗

bioRxiv2026

AffectRoute: Role-Structured EEG and Peripheral Physiology for Subject-Independent Affect Regression

Subject-independent affect regression from physiological signals remains challenging because emotional responses vary substantially across individuals, widely used datasets provide only coarse trial-level annotations, and heterogeneous physiological modalities may not contribute reliably when treated as if they were interchangeable predictors. We have developed AffectRoute, a protocol-conditioned subject-independent affect regression that is conditioned on the protocol and assigns separate predictive functions to information from the population, electroencephalography (EEG), and peripheral physiological signals (PPS). First, a source-population prior establishes a trial-level affective anchor using only the data from source participants. TrajBridge then combines an EEG representation that is supervised by REFED for participant-specific adjustments with temporal structure obtained from the continuous REFED annotations in order to create a weakly supervised segment-resolved pseudo-trajectory and to establish a frozen trial-level baseline. PhysioRoute next reduces the remaining error by breaking down the residual correction into a source-derived direction, which is estimated from the out-of-fold residuals within the source group, and a channel-specific magnitude derived from the PPS. When evaluated on DEAP and DREAMER using a leave-one-subject-out approach at the participant level, AffectRoute showed consistent step-by-step improvements in both the mean absolute error and the concordance correlation coefficient. A method that relied solely on the source data was clearly worse than PhysioRoute, showing that the final improvement cannot be accounted for by transferable source residual regularity alone. Conventional alternatives to fusing the PPS were also found to be consistently less effective, although analyses at the channel level and with a leave-one-channel-out design showed that the peripheral contributions are axis-dependent yet distributed across channels. These results indicate that structured residual inference is an effective alternative to unrestricted multimodal fusion for subject-independent affect regression.

neuroscience↗

bioRxiv2026

Cross-Kingdom Control: Yeast Prion Protein Modulates Host Physiology in Drosophila

Prions, once mainly studied for their pathogenic roles, are now gaining recognition as adaptive elements in microbial physiology. Over one-third of wild yeast isolates harbor prion proteins, yet their impact on host-microbe interactions remains poorly characterized. Given the ecological dominance of yeasts in the Drosophila mycobiome, we leveraged the Drosophila melanogaster-Saccharomyces cerevisiae system to investigate how the mycobiome-derived prion, [MRPL10+], modulates host physiology. We show that flies exposed to [MRPL10+] yeast exhibit significantly enhanced cold tolerance and increased locomotor activity. This effect persists with heat-killed yeast and diluted culture, suggesting a stable, potent bioactive factor. Using the genetically diverse Drosophila Global Diversity Lines (GDL), we identified natural variation in responsiveness to [MRPL10+] yeast. Genome-wide association and functional RNAi screening revealed a gut-brain signaling axis involving genes critical for digestion, intercellular communication, transcription regulation, and neural transmission. Notably, serotonin and octopamine pathways were essential for [MRPL10+]-induced changes in cold tolerance and locomotion, implicating neuromodulatory circuits in prion-mediated microbial signaling. Our findings establish a mechanistic link between a fungal prion and host metabolic and neural adaptation. This work provides the first genetic dissection of a prion-mediated host-microbe interaction, laying the groundwork for investigating beneficial prions in complex microbial communities and highlighting a new dimension of the mycobiomes influence on animal physiology.

evolutionary biology↗

bioRxiv2026

Beyond establishment: incorporating physiological performance into predictions of invasion risk

Biological invasions are a major driver of global change, reshaping ecosystems and threatening biodiversity worldwide. Anticipating where invaders will establish and where they will exert the strongest ecological impacts are key challenges for early detection and targeted management. Although Species Distribution Models (SDMs) are widely used to forecast biological invasions, they often provide uncertain estimates of establishment ranges and limited insight into invader performance, making it difficult to anticipate ecological impacts. Here, we address these limitations by integrating physiological information on invader performance with SDMs to identify regions of high invasion risk. Using the brown alga Rugulopteryx okamurae, one of the most prominent marine invaders in Europe, we first test alternative hypotheses of northern establishment limits: (i) a cold-survival constraint driven by winter temperatures and (ii) a growth constraint derived from the species' thermal performance. To identify the more likely scenario, we combine cold-tolerance experiments with seasonal growth comparisons between the invader and a native macroalga Dictyota dichotoma, whose established distribution allows physiological performance to be directly related to realised presence. Finally, we project seasonal growth of the invader across the predicted establishment range as a proxy for biomass accumulation and potential ecological impacts. Our results indicate that northern limit in Europe will be more likely constrained by winter survival rather than growth, extending the potential establishment range of Rugulopteryx to mid-Norway. In contrast, the highest impacts are likely to remain concentrated in southern Europe, where thermal conditions sustain high year-round growth. Overall, our approach illustrates how understanding the physiological response of invaders to their environment can improve the interpretation of SDM outputs and help identify areas at greatest risk of impact within their potential establishment range.

ecology↗

bioRxiv2026

Bacteriostatic lethality emerges from turgor-induced physiological stress

With new antibiotic discovery slowing, maximizing the efficacy of existing drugs is crucial. Bacteriostatic antibiotics are regarded as inferior to bactericidal drugs because they are thought to merely arrest growth without inflicting cellular damage and cell death. Contrary to conventional views, we show that bacteriostasis is a physiologically stressed state, which can be exploited to unmask its lethality. Through quantitative measurements and live-cell imaging, we found that translation inhibition by bacteriostatic antibiotics induces intracellular turgor pressure buildup by perturbing physiological balance in E. coli. This pressure manifests as osmotic swelling, leading to lysis in a subset of cells, while surviving cells depend on PBP1-mediated cell-wall repair, which alleviates mechanical strain. This protective mechanism led us to predict, and we experimentally confirmed, that inactivating PBP1 with a {beta}-lactam amplifies the lethality of bacteriostatic drugs, challenging the general assumption of antagonism between bacteriostatic and bactericidal antibiotics. These findings show bacteriostasis as a physiologically unstable state and provide a systems-level framework for its lethality, enabling the rational design of optimized therapies.

microbiology↗

bioRxiv2026

A Physiologically Detailed Biomechanical Model of the Mouse Distal Forelimb for Simulation of Fine Motor Control

This study presents a physiologically detailed biomechanical model of the mouse distal forelimb that incorporates intrinsic musculature, tendon routing, and digit-level skeletal anatomy, features simplified or omitted in existing musculoskeletal models. Using high-resolution anatomical reconstruction and computational modeling, we created a physiological representation of the wrist and digits capable of simulating complex forelimb movements. The model enables simulation of coordinated distal forelimb movement and digit-level muscle behavior during grasping-related tasks. Simulations were performed for multiple tasks, including grasping, grasping with supination, wrist flexion, and digit I flexion, with analysis focused on the grasping task due to its integration of both intrinsic and extrinsic musculature. Model performance was evaluated through comparisons of marker trajectories between torque-driven reference motion and muscle-driven simulations, temporal shuffle control, and comparisons between experimentally recorded electromyography (EMG) activity and model-predicted muscle excitation profiles. The model successfully reproduced coordinated distal forelimb kinematics, demonstrated strong agreement between torque-driven and muscle-driven simulation approaches, and generated physiologically plausible muscle excitation patterns consistent with experimentally observed EMG activity during grasping-related movement. These findings establish the model as a framework for studying fine motor control, neuromuscular coordination, and movement-related impairments in mice while providing a foundation for future investigation of neurological disorders and their underlying biomechanical mechanisms.

bioengineering↗

bioRxiv2026

Developmental and physiological profiles define drought response diversity and genomic associations in common bean

Common bean (Phaseolus vulgaris L.) yields are strongly impacted by water deficit, yet there is substantial within-species diversity in how development, biomass accumulation, gas exchange, and photosynthetic performance are coordinated under stress. Based on this variation within a diversity panel, we characterise response profiles, define drought-response strategies, assess how these strategies relate to population structure and gene flow, and identify associated loci. A panel of 142 common bean accessions representing diverse genetic backgrounds was grown outdoors under controlled water-deficit conditions. Over five weeks, plants were monitored for phenology, biomass, pod production, and leaf traits related to stomatal and photosynthetic performance, including a brief recovery period. Genome-wide association analyses were then performed for developmental, physiological and recovery-related traits. Declining soil water availability revealed marked variation among accessions in developmental progression, biomass partitioning, stomatal behaviour and photosynthetic performance. We combined developmental and physiological traits to define above-ground response profiles and classify drought-response strategies in common bean, which were distributed across the diversity panel. GWAS identified multiple QTL and candidate loci associated with developmental, physiological and recovery-related traits. Common bean exhibits extensive diversity in overall above-ground responses to water deficit, likely reflecting local adaptation rather than population structure. Developmental data were essential for differentiating response strategies and, when combined with porometer and fluorometer measurements indicating the level of water stress experienced by the plants, for connecting traits and strategies to genomic variation. These results provide trait relationships, candidate loci and testable hypotheses for validation across environments and for future breeding-oriented studies.

plant biology↗

bioRxiv2026

Physiological Aging and Cardiovascular Disease Distinctly Remodel the Human Cardiac Lymphatic Endothelium

Aims: Cardiac lymphatic endothelial cells (LECs) regulate tissue homeostasis, immune trafficking, and remodeling, but how human cardiac LEC heterogeneity changes with physiological aging and cardiovascular disease remains poorly defined. We sought to define age- and disease-associated LEC states, their regulatory and microenvironmental programs, and the functional relevance of selected pathways. Methods and results: We integrated human cardiac single-nucleus transcriptomic datasets spanning physiological aging, dilated and hypertrophic cardiomyopathy, doxorubicin-associated cardiomyopathy, and heart failure with preserved ejection fraction. Aging redistributed LECs among pre-existing states, with expansion of a homeostatic immune-surveillance state and loss of cytokine-responsive and polarity-associated states. Cardiovascular diseases showed a distinct trajectory, with depletion of a non-failing homeostatic state and expansion of shared and disease-associated remodeling states. SCENIC and NicheNet/MultiNicheNet identified state-specific regulatory programs and disease-dependent signaling networks, with recurrent BMP/TGF-{beta}/activin-family signaling. ACVR2A was prioritized in human doxorubicin-associated cardiomyopathy; endothelial Acvr2a deletion in aged doxorubicin-treated mice was associated with improved cardiac function and increased open cardiac lymphatic vessels. Independent human spatial transcriptomic analyses supported selected aging- and disease-associated programs. Conclusion: Physiological aging and cardiovascular disease remodel cardiac LECs through distinct changes in cellular state, transcriptional regulation, and microenvironmental signaling. Aging is associated with redistribution and reduced representation of specialized LEC programs, whereas cardiovascular diseases redirect LECs through disease-associated signaling environments, highlighting context-dependent remodeling of the cardiac lymphatic endothelium across aging and disease.

bioinformatics↗

bioRxiv2026

A comprehensive physiological dataset of pain and aversive modalities for pain biomarkers research

While progress has been made in identifying pain biomarkers using neuroimaging, the development of reliable EEG-based biomarkers remains challenging, limited by small sample sizes and the lack of adequate control conditions. We present a comprehensive dataset from 125 pain-free adults, comprising electroencephalogram (EEG) recordings, and behavioural, sociodemographic, and psychological data. Galvanic skin response and electrocardiogram data were also recorded in a subset of participants (n = 76). Participants received two sustained painful stimulations (thermal, chemical) and two sustained aversive non-painful stimulations (auditory, taste), each delivered twice (with and without continuous intensity ratings). Data are provided in Brain Imaging Data Structure format, where all physiological, stimulus-related, and behavioural data are synchronized within the EEG data files for easy access and analysis. Technical validation confirmed data integrity, with spectral and physiological analyses showing responses associated with stimulus intensity and subjective pain/unpleasantness levels. By providing multimodal physiological data across painful and non-painful aversive conditions, this initiative represents a valuable resource for developing or validating biomarkers and exploring the multidimensional nature of pain perception.

neuroscience↗

bioRxiv2026

Hydrodynamics structure the physiological trajectory and bloom dynamics of a harmful diatom species across neighboring coastal ecosystems

Hydrodynamics is a strong regulator of phytoplankton cell densities and population connectivity. However, the extent to which hydrodynamics, specifically dilution and advection, dictates the internal physiological state and overall bloom dynamics remains poorly understood. We conducted an integrated study of the harmful diatom Pseudo-nitzschia australis in two neighboring coastal bays with similar abiotic conditions but contrasting bloom trajectories. Using a combination of field observations, transcriptomics, domoic acid (DA) measurements, and hydrodynamic simulations, we show that a three-fold difference in dilution rates alone explains a 25-day shift in bloom timing and an order-of-magnitude difference in cell densities. Transcriptomic profiling revealed distinct metabolic and stress-associated gene modules that synchronized with hydrodynamically-mediated nutrient depletion rate, linking residence times to cellular mortality. Furthermore, directional connectivity between the bays may explain population-level toxin heterogeneity, as advection of older cells, releasing DA outside the cells, may have decreased the proportion of intracellular DA in the destination bay. Our results illustrate that hydrodynamics do not merely modulate population transport; they structure the full physiological life cycle of a bloom, from initiation to nutrient-driven demise. This highlights the necessity of considering hydrodynamics as a primary explanation for bloom dynamics with cascading effects on bloom onset, cell density, nutrient consumption, cell physiology and mortality.

ecology↗

bioRxiv2026

Fiber-Coupled Rotating Two-Photon Light-Sheet Microscopy for Physiological Vestibular Imaging in Larval Zebrafish

Physiological vestibular stimulation requires macroscopic rotation of the animal, making simultaneous high-resolution neural imaging technically demanding. Here we present a fiber-coupled rotating two-photon light-sheet microscope for physiological pitch-axis vestibular imaging in larval zebrafish. Two-photon excitation is attractive in this context because near-infrared excitation avoids visible-light contamination of the visual environment. Femtosecond pulses were delivered to the rotating microscope through a broadband hollow-core negative-curvature fiber previously characterized in static light-sheet configurations. The rotating instrument maintained the axial mechanical stability required for cellular-resolution imaging, with submicron mean axial displacement over the characterized angular range. Fiber performance under rotation was also stable: bend-induced transmission changes were small in the relevant curvature regime, and circular input polarization suppressed rotation-dependent polarization artefacts to below 1\% in the sample plane. The dominant rotation-sensitive optical limitation was not the fiber but perturbation of the thermal lens in the sample chamber. Reducing fluid motion along the excitation path suppressed this artefact and restored stable imaging during dynamic rotation. With this system, we recorded brain-wide vestibular responses during sinusoidal pitch stimulation and resolved anatomically organized cellular response patterns across the brain. These results establish rotating two-photon light-sheet microscopy as a practical solution for vestibular imaging in experiments that require physiological stimulation together with darkness or controlled visual conditions.

neuroscience↗

bioRxiv2016

The Divisive-Normalization Model of V1 Neurons: A Comprehensive Comparison of Physiological Data and Model Predictions

The physiological responses of simple and complex cells in the primary visual cortex (V1) have been studied extensively and modeled at different levels. At the functional level, the divisive normalization model (DNM, Heeger, 1992) has accounted for a wide range of single-cell recordings in terms of a combination of linear filtering, nonlinear rectification, and divisive normalization. We propose standardizing the formulation of the DNM and implementing it in software that takes static grayscale images as inputs and produces firing-rate responses as outputs. We also review a comprehensive suite of 30 empirical phenomena and report a series of simulation experiments that qualitatively replicate dozens of key experiments with a standard parameter set consistent with physiological measurements. This systematic approach identifies novel falsifiable predictions of the DNM. We show how the model simultaneously satisfies the conflicting desiderata of flexibility and falsifiability. Our key idea is that, while adjustable parameters are needed to accommodate the diversity across neurons, they must be fixed for a given individual neuron. This requirement introduces falsifiable constraints when this single neuron is probed with multiple stimuli. We also present mathematical analyses and simulation experiments that explicate some of these constraints.

physiology↗

bioRxiv2019

Physiological networks governing salinity tolerance potentials in Gossypium hirsutum germplasm

Toxic ions begin to accumulate in tissues of salt-stressed plants after the initial osmotic shock. In glycophytes, the ability to mobilize or sequester excess ions define tolerance mechanisms. Mobilization and sequestration of excess Na+ involves three transport mechanisms facilitated by the plasma membrane H+/Na+ antiporter (SOS1), vacuolar H+/Na+ antiporter (NHX1), and Na+/K+ transporter in vascular tissues (HKT1). While the cultivated Gossypium hirsutum (upland cotton) is significantly more tolerant to salinity relative to other crops, the critical factors contributing to the observed variation for tolerance potential across the germplasm has not been fully scrutinized. In this study, the spatio-temporal patterns of Na+ accumulation at different severities of salt stress were investigated across a minimal comparative panel representing the spectrum of genetic diversity across the improved cotton germplasm. The goal was to define the importance of integrative or network effects relative to the direct effects of Na+ homeostasis mechanisms mediated by GhHKT1, GhSOS1, and GhNHX1. Multi-dimensional physio-morphometric attributes were investigated in univariate and multivariate statistical contexts, as well as the relationship between variables using structural equation modeling. Results showed that mobilized or sequestered Na+ may contribute to the baseline salinity tolerance, but the observed variance in overall tolerance potential across a meaningful subset of the germplasm were more significantly associated to antioxidant capacity, maintenance of stomatal conductance, chlorophyll content, and divalent cations, and other physiological interactions occurring through complex networks. One-Sentence SummaryVariation in salinity tolerance potential across the tetraploid cultivated Gossypium germplasm is better explained by complex physiological networks rather than just cellular Na+ homeostasis.

physiology↗