Biology subjects

Ezer, D.

Publications and source records attributed to Ezer, D..

18 recordsLinked to original sources

bioRxiv2026

Harnessing within-cultivar variation to identify hidden genetic resistance using single plant-omics

Fusarium graminearum is a fungal pathogen that causes scab or head blight in small grain cereals and threatens global cereal production. Disease progression varies widely among individual plants of the same cultivar, reflecting both genetic and environmental heterogeneity. This complicates the identification of early host responses, because each individual plant in a population is at a slightly different phase of disease progression. Here we apply single plant-transcriptomics to a population of 121 malt-barley exposed to F. graminearum, enabling us to reconstruct a temporal sequence of regulatory processes during early infection. We identified several disease-resistance associated genetic variants that are already endemic in this high-yielding cultivar, suggesting potential as breeding targets. These variants were within proteins involved in ROS-burst production, a lectin-kinase PRR, and enzymes with DON-detoxification activity. Single plant-transcriptomics offers a novel strategy for characterising early plant-pathogen interactions, turning intra-population heterogeneity from an experimental barrier into an asset.

plant biology↗

bioRxiv2026

Bridging human and plant adaptations for climate resilience

O_LIClimate change is reshaping agriculture through both gradual shifts and increasingly unpredictable extremes. Plants cope using developmental plasticity and bet-hedging, but it is unclear how these biological strategies align with the ways farmers perceive and respond to climate risks. This study investigates: (1) whether farmers understand climate change as incremental trends or recurrent shocks, (2) how their adaptations parallel plant plasticity and bet-hedging, and (3) under which climate scenarios these adaptations best support yield stability. C_LIO_LIWe combined qualitative research and modelling by conducting fifty semi-structured interviews with farmers, agricultural associations and public administrators across three climatically distinct Italian regions, and by developing an agent-based stochastic simulation that represents farmer-like plasticity (delayed sowing) and bet-hedging (staggered sowing) under drought and flood scenarios. C_LIO_LIFarmers described climate change as both gradual transformation and intensifying volatility. Their adaptive responses - adjusting calendars, switching crops and diversifying production - closely aligned with plant strategies, though articulated in practical rather than scientific terms. Simulation results showed that plasticity enhanced yields under systematic shifts in conditions, whereas bet-hedging reduced losses in highly variable climates characterised by frequent transitions between extremes. C_LIO_LITogether, the qualitative and modelling findings demonstrate that plant and farmer adaptation logics converge in complementary ways. Plasticity supports performance under gradual change, while bet-hedging buffers unpredictability. These insights highlight the potential for co-designed tools that link plant traits, farmer decision-making and ecological risk, strengthening climate-resilient agricultural planning and improving communication between farmers, breeders and plant scientists. C_LI Societal Impact StatementClimate change is transforming agriculture through both gradual shifts and increasingly unpredictable extremes, challenging farmers ability to protect crops and livelihoods. This study brings together farmer experiences and plant adaptation strategies to explore how people and plants respond to similar climate pressures. By showing that farmers practices mirror plant plasticity and bet-hedging, our findings highlight opportunities to design climate-resilient agriculture that aligns biological traits with real-world decision-making. This work can inform plant breeders, extension services and policymakers seeking to support farmers through clearer communication, better risk-management tools and more adaptable crop varieties, ultimately strengthening resilience in food systems.

plant biology↗

bioRxiv2026

TimeTraits: extracting functional traits from biological time-series in R

SummaryTimeTraits provides a series of functions to enable the extraction of parameters from time series data using Functional Data Analysis methods. We demonstrate its utility in dissecting the changes in curve shape of a circadian clock bioluminescence marker, following a photoperiod shift in wildtype and phyB Arabidopsis. Availability and ImplementationTimeTraits is available in CRAN: https://cran.r-project.org/web/packages/TimeTraits/readme/README.html

plant biology↗

bioRxiv2025

The plant circadian clock exerts stronger control over the diel proteome than the transcriptome

AbstractThe plant circadian clock is a genetic circuit composed of multiple mutually-regulating transcription factors that together synchronize internal biological rhythms to the [~]24-hour period of planetary rotation. While it has been known for over a decade that nearly 40% of the transcriptome in the model plant Arabidopsis oscillates with a circadian rhythm, it is yet unclear to what extent this translates to the proteome. Here, through parallel quantitative proteome and transcriptome time-course profiling of Arabidopsis wild-type plants and a panel of clock deficient plant lines, we show that specific clock genes exercise extensive control over diel proteome rhythmicity, and to a much greater extent than they do the transcriptome. This control results in a clock-dependent synchronization of rhythmic proteins along a bimodal phase distribution that is lost in circadian clock deficient plants. This suggests pervasive post-translational control of gene expression by specific elements of the circadian system, notably the morning expressed LHY/CCA1 module. Our findings imply that the circadian clock exercises much greater control of gene expression through proteostasis mechanisms than previously recognised, necessitating a recalibration of our current understanding of clock proteins as primarily transcriptional regulators.

plant biology↗

bioRxiv2025

Accurately Programming Complex Light Regimes with Multi-channel LEDs

BackgroundAdvances in LED lighting technologies have allowed researchers to explore increasingly complex light regimes. This has given us greater insight into plants responses to dynamic light, including seasonality and fluctuating conditions, rather than the discrete (i.e. on / off) lighting previously explored. However, there is a need for methods to accurately program multi-channel / waveband LED lighting systems. ResultsWe present a multi-step, multidimensional algorithm to accurately program LED lights. This algorithm accounts for non-linearity between intensity settings and irradiance output, as well as bleedthrough between channels of different wavebands. Our algorithm out-performs other methods which treat waveband channels as independent variables, more accurately predicting intensity settings to achieve a desired irradiance when using multiple LED channels. ConclusionsThis algorithm allows the community to accurately program complex light regimes to probe plant responses to dynamically changing light spectra. We have made this algorithm available to the plant science community as an R package, LightFitR (available on GitHub at: https://github.com/ginavong/LightFitR).

plant biology↗

bioRxiv2025

ELF3 controls trait heterogeneity by tuning the rate of maturation in Arabidopsis and barley

Trait heterogeneity in a population increases the likelihood that some individuals will survive an unpredictable environmental stress. Individual plants mature at different rates due to genetics, environmental factors, and random chance. All of this contributes to trait heterogeneity. EARLY FLOWERING3 (ELF3), a core circadian clock component, determines developmental timing, and here we tested the hypothesis that it would shape trait heterogeneity. We developed a model predicting that faster-developing populations exhibit greater heterogeneity during development but reduced heterogeneity at maturity, while slower-growing populations show the opposite pattern. Experiments in Arabidopsis elf3 and barley Hvelf3 mutants supported this prediction. In Arabidopsis, ELF3 controlled hypocotyl elongation variability via maturation rate rather than direct regulation. Bolting time heterogeneity also decreased in faster-growing plants. In barley, Hvelf3 altered growth heterogeneity, but this was initially masked by germination timing differences. Finally, smaller barley plants were found to be more resilient to osmotic stress, suggesting that ELF3-driven trait heterogeneity may contribute to bet hedging. These findings highlight how modifying developmental rates influences population-level trait distributions and stress resilience.

plant biology↗

bioRxiv2025

The genetic basis for synchronized time perception in plant populations

Synchronised developmental timing is important for ensuring crop uniformity and high yields. However, climate change is leading to crops being grown at different latitudes, varying their exposures to photoperiods over seasons and impacting developmental timings. We investigated whether the response of circadian rhythms in seedlings to changes in photoperiod would enable us to predict the timing and synchronization of flowering. Indeed, we show that the same Quantitative Trait Loci (QTLs) are associated to circadian traits in seedlings and developmental traits during bolting, using the first recombinant inbred lines (RILs) between African and European Arabidopsis lineages, spanning diverse latitudes. Two QTLs contain K-Homology Domain RNA binding proteins (KH17, KH29) and are associated with splicing variants in known flowering genes, MADS AFFECTING FLOWERING2 and 3 (MAF2, MAF3), including generating chimeric transcripts, a potential mechanism for accelerated proteome evolution. Natural variants in KH17, including in its prion-like domain, are associated with de-coupling the mean and synchronization of flowering time, enabling greater adaptation of population-level heterogeneity in developmental timings. Our results suggest that circadian traits in seedlings could be used to screen for agriculturally relevant developmental traits in mature plants, enabling efficient breeding of climate-resilient crops.

plant biology↗

bioRxiv2024

Stable and dynamic gene expression patterns over diurnal and developmental timescales in Arabidopsis thaliana

O_LIDevelopmental processes are known to be circadian regulated in plants. For instance, the circadian clock regulates genes involved in the photoperiodic flowering pathway and the initiation of leaf senescence. Furthermore, signals which entrain the circadian clock, such as energy availability, are known to vary in strength over plant development. However, diurnal oscillations of the Arabidopsis transcriptome have typically been measured in seedlings. C_LIO_LIWe collected RNA-seq data from Arabidopsis leaves over developmental and diurnal timescales, concurrently: every 4 hours per day, on 3 separate days after a synchronised vegetative-to-reproductive transition. Gene expression varied more over the developmental timescale than on the diurnal timescale, including genes related to a key energy sensor: the Sucrose non-fermenting-1-related protein kinase (SnRK1) complex. C_LIO_LIMoreover, regulatory targets of core clock genes displayed changes in rhythmicity and amplitude of expression over development. Cell-type-specific expression showed diurnal patterns that varied in amplitude, but not phase, over development. Some previously identified qRT-PCR housekeeping genes display undesirable levels of variation over both timescales. We identify which common qRT-PCR housekeeping genes are most stable across developmental and diurnal timescales. C_LIO_LIIn summary, we establish the patterns of circadian transcriptional regulation over plant development, demonstrating how diurnal patterns of expression change over developmental timescales. C_LI

plant biology↗

bioRxiv2024

Harnessing light heterogeneity to optimise controlled environment agriculture

Yield is impacted by the environmental conditions that plants are exposed to. Controlled environmental agriculture provides growers with an opportunity to fine-tune environmental conditions for optimising yield and crop quality. However, space and time constraints will limit the number of experimental conditions that can be tested, which will in turn limit the resolution to which environmental conditions can be optimised. Here we present an innovative experimental approach that utilises the existing heterogeneity in light quantity and quality across a vertical farm to evaluate hundreds of environmental conditions concurrently. It proposes a three-phase workflow for identifying critical light variables, which can guide targeted improvements in yield and energy use. Using an observational study design, we identify features in light quality that are most predictive of biomass in different microgreens crops (kale, radish and sunflower) that may inform future iterations of lighting technology development for vertical farms. The findings suggest that light quality, rather than just light intensity, plays a crucial role in uniform crop yields and that light sensitivities are variety-specific, highlighting the importance of tailored light recipes for different crops.

plant biology↗

bioRxiv2024

Hypocotyl Development in Arabidopsis and other Brassicaceae Displays Evidence of Photoperiodic Memory

Sensing and responding to photoperiod changes is essential for plants to adapt to seasonal progression. Most of our understanding of how plants sense photoperiodic changes is through studies on flowering time. However, other aspects of plant development are regulated by the photoperiod, including hypocotyl elongation. Unlike flowering, hypocotyl elongation displays a greater plasticity to changes in the photoperiod with increases in daylength causing greater inhibition of growth until a threshold is met. Previous studies have only looked at hypocotyl development in the context of a stationary photoperiod. It is unknown if changes in the photoperiod during development influence hypocotyl elongation. Here, we developed a physiological assay to investigate this question. We have discovered that hypocotyl elongation is influenced by a memory of past photoperiod exposure in Arabidopsis and Brassicaceae cultivars used for microgreen agriculture. Photoperiodic memory persisted for multiple days, although it weakened over time, and the strength of the memory was dependent on the genetic background. We identified that phyB and ELF3, key regulators of hypocotyl development, were required for photoperiodic memory. Finally, we identified that the circadian clock is unlikely to function as a repository for photoperiodic memory as circadian rhythms quickly re-aligned with the new photoperiod. In summary, our work highlights for the first-time evidence of a photoperiodic memory that can control plant development.

plant biology↗

bioRxiv2023

An Arabidopsis leaf expression atlas across diurnal and developmental scales

Mature plant leaves are a composite of distinct cell types, including epidermal, mesophyll and vascular cells. Notably the proportion of these cells, and the relative transcript concentrations within different cell types may change over time. While gene expression data at a single-cell level can provide cell-type specific expression values, it is often too expensive to perform this on high resolution time series. Although bulk RNA-seq can be performed in a high resolution time series, the RNA-seq in whole leaves measures the average gene expression values across all cell types in each sample. In this study, we combined single cell RNA-seq data with time-series data from whole leaves to infer an atlas of cell type-specific gene expression changes over time for Arabidopsis thaliana. We inferred how relative transcript concentrations of cell types vary across diurnal and developmental time scales. Importantly this analysis revealed three sub-groups of mesophyll cells that have distinct temporal profiles of expression. Finally, we develop tissue-specific gene networks that form a new community resource: An Arabidopsis Leaf Time-Dependent Atlas (AraLeTa), which allows users to extract gene networks that are confirmed by transcription factor binding data and specific to certain cell types, at certain times of day and certain developmental stages, which is available at: https://regulatorynet.shinyapps.io/araleta/.

plant biology↗

bioRxiv2023

Single-plant-omics reveals the cascade of transcriptional changes during the vegetative-to-reproductive transition

Plants undergo rapid developmental transitions, as well as gradual developmental processes. Moreover, individual plants within a population will undergo the developmental transitions asynchronously, so it is difficult to assemble a time series to resolve the sequence of transcriptional changes that take place during these rapid transitions. Single-plant-omics has the potential to distinguish between transcriptional events that are associated with these binary and continuous processes. Furthermore, we can utilise single-plant-omics to exploit this developmental asynchrony to order individual plants by their developmental trajectory, revealing a detailed cascade of transcriptional events. Here, we utilise single-plant-transcriptomics to resolve the transcriptional events that coincide with the onset of bolting. We performed RNA-seq on the leaves of individual plants from a large population of wild type Arabidopsis thaliana replicated at one time point during the vegetative-to-reproductive transition. Even though more than half of transcripts were differentially expressed between bolted and unbolted plants, we were able to find a subset of regulators that were more closely associated with gradual developmental traits like leaf size and biomass. Using a novel pseudotime inference algorithm, we determined that some senescence-associated processes, such as the reduction in ribosome biogenesis, are evident in the transcriptome before a bolt is visible. These results show the potential of single-plant-omics to reveal the detailed sequence of events that occur during rapid developmental transitions. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=179 SRC="FIGDIR/small/557157v1_ufig1.gif" ALT="Figure 1"> View larger version (28K): org.highwire.dtl.DTLVardef@c50448org.highwire.dtl.DTLVardef@9c384aorg.highwire.dtl.DTLVardef@33c336org.highwire.dtl.DTLVardef@55302e_HPS_FORMAT_FIGEXP M_FIG Graphical Abstract: Physiological changes around bolting can be categorised into: binary processes, which appear to have either occurred or not occurred at any given timepoint; or continuous processes, which can be observed quantitatively. For binary processes, expression of strongly correlated genes can appear to follow a step change dynamic over time. However, when considered over a shorter timescale, the dynamics appear much smoother. For continuous processes, the shorter timescale should also capture smooth changes in gene expression. C_FIG

plant biology↗

bioRxiv2023

Complex epistatic interactions between ELF3, PRR9, and PRR7 regulates the circadian clock and plant physiology

Circadian clocks are endogenous timekeeping mechanisms that coordinate internal physiological responses with the external environment. EARLY FLOWERING3 (ELF3), PSEUDO RESPONSE REGULATOR (PRR9), and PRR7 are essential components of the plant circadian clock and facilitate entrainment of the clock to internal and external stimuli. Previous studies have highlighted a critical role for ELF3 in repressing the expression of PRR9 and PRR7. However, the functional significance of activity in regulating circadian clock dynamics and plant development is unknown. To explore this regulatory dynamic further, we firstly employed mathematical modelling to simulate the effect of the prr9/prr7 mutation on the elf3 circadian phenotype. These simulations suggested that simultaneous mutations in prr9/prr7 could rescue the elf3 circadian arrythmia. Following these simulations, we generated all Arabidopsis elf3/prr9/prr7 mutant combinations and investigated their circadian and developmental phenotypes. Although these assays could not replicate the results from the mathematical modelling, our results have revealed a complex epistatic relationship between ELF3 and PRR9/7 in regulating different aspects of plant development. ELF3 was essential for hypocotyl development under ambient and warm temperatures, while PRR9 was critical for root thermomorphogenesis. Finally, mutations in prr9 and prr7 rescued the photoperiod insensitive flowering phenotype of the elf3 mutant. Together, our results highlight the importance of investigating the genetic relationship amongst plant circadian genes.

plant biology↗

bioRxiv2022

Integrative metabolomics reveal the organisation of alkaloid biosynthesis in Daphniphyllum macropodum

Daphniphyllum alkaloids are structurally diverse nitrogen-containing compounds with polycyclic, stereochemically rich carbon skeletons. Understanding how plants biosynthesise these compounds may lead to greater access to allow exploration of bioactivities; however, very little is known about their biosynthetic origins. Here, we integrated metabolomics approaches to map alkaloid distribution across Daphniphyllum macropodum plants and tissues. We generated a novel untargeted metabolomics workflow to highlight trends in alkaloid distribution across tissues, using a holistic approach that does not rely on ambiguous peak annotations. Both liquid-chromatography-mass spectrometry and mass-spectrometry imaging analyses independently revealed that alkaloids have a pattern of spatial distribution based on their skeletal subtypes. The distinct alkaloid subtype localisation suggests the biosynthetic pathway is controlled spatially with intermediates transported from the phloem to the epidermis where they undergo additional derivatization. This study sets the stage for the future work on Daphniphyllum alkaloid biosynthesis and highlights how integrating different metabolomics strategies can reveal valuable insights on these compounds distribution within the plant.

plant biology↗

bioRxiv2020

Reconstructing Genotypes in Private Genomic Databases from Genetic Risk Scores

Some organisations like 23andMe and the UK Biobank have large genomic databases that they re-use for multiple different genome-wide association studies (GWAS). Even research studies that compile smaller genomic databases often utilise these databases to investigate many related traits. It is common for the study to report a genetic risk score (GRS) model for each trait within the publication. Here we show that under some circumstances, these GRS models can be used to recover the genetic variants of individuals in these genomic databases--a reconstruction attack. In particular, if two GRS models are trained using a largely overlapping set of participants, then it is often possible to determine the genotype for each of the individuals who were used to train one GRS model, but not the other. We demonstrate this theoretically and experimentally by analysing the Cornell Dog Genome database. The accuracy of our reconstruction attack depends on how accurately we can estimate the rate of co-occurrence of pairs of SNPs within the private database, so if this aggregate information is ever released, it would drastically reduce the security of a private genomic database. Caution should be applied when using the same database for multiple analysis, especially when a small number of individuals are included or excluded from one part of the study.

genomics↗

bioRxiv2019

DEK influences the trade-off between growth and arrest via H2A.Z-nucleosomes in Arabidopsis

The decision of whether to grow and proliferate or to restrict growth and develop resilience to stress is a key biological trade-off. In plants, constitutive growth results in increased sensitivity to environmental stress1,2. The underlying mechanisms controlling this decision are however not well understood. We used temperature as a cue to discover regulators of this process in plants, as it both enhances growth and development rates within a specific range and is also a stress at extremes. We found that the conserved chromatin-associated protein DEK plays a central role in balancing the response between growth and arrest in Arabidopsis, and it does this via H2A.Z-nucleosomes. DEK target genes show two distinct categories of chromatin architecture based on the distribution of H2A.Z in +1 nucleosome and gene body, and these predict induction or repression by DEK. We show that these chromatin signatures of DEK target genes are conserved in human cells, suggesting that DEK may act through an evolutionarily conserved mechanism to control the balance between growth and arrest in plants and animals.

plant biology↗

bioRxiv2018

Selection of time points for costly experiments: a comparison between human intuition and computer-aided experimental design

MotivationThe design of an experiment influences both what a researcher can measure, as well as how much confidence can be placed in the results. As such, it is vitally important that experimental design decisions do not systematically bias research outcomes. At the same time, making optimal design decisions can produce results leading to statistically stronger conclusions. Deciding where and when to sample are among the most critical aspects of many experimental designs; for example, we might have to choose the time points at which to measure some quantity in a time series experiment. Choosing times which are too far apart could result in missing short bursts of activity. On the other hand, there may be time points which provide very little information regarding the overall behaviour of the quantity in question.\n\nResultsIn this study, we design a survey to analyse how biologists use previous research outcomes to inform their decisions about which time points to sample in subsequent experiments. We then determine how the choice of time points affects the type of perturbations in gene expression that can be observed. Finally, we present our main result: NITPicker, a computational strategy for selecting optimal time points (or spatial points along a single axis), that eliminates some of the biases caused by human decision-making while maximising information about the shape of the underlying curves, utilising ideas from the field of functional data analysis.\n\nAvailabilityNITPicker is available on GIThub (https://github.com/ezer/NITPicker).

bioinformatics↗

bioRxiv2017

The G-box transcriptional regulatory code in Arabidopsis

Plants have significantly more transcription factor (TF) families than animals and fungi, and plant TF families tend to contain more genes--these expansions are linked to adaptation to environmental stressors (1, 2). Many TF family members bind to similar or identical sequence motifs, such as G-boxes (CACGTG), so it is difficult to predict regulatory relationships. We determine that the flanking sequences near G-boxes help determine in vitro specificity, but that this is insufficient to predict the transcription pattern of genes near G-boxes. Therefore, we construct a gene regulatory network that identifies the set of bZIPs and bHLHs that are most predictive of the gene expression of genes downstream of perfect G-boxes. This network accurately predicts transcriptional patterns and reconstructs known regulatory subnetworks. Finally, we present Ara-BOX-cis (araboxcis.org), a website that provides interactive visualisations of the G-box regulatory network, a useful resource for generating predictions for gene regulatory relations.

plant biology↗