Biology subjects

Fichman, Y.

Publications and source records attributed to Fichman, Y..

15 recordsLinked to original sources

bioRxiv2025

Identification of a putative RBOHD-FERONIA-CRK10-PIP2;6 plasma membrane complex that interacts with phyB to regulate ROS production in Arabidopsis thaliana

O_LIReactive oxygen species (ROS) regulate plant growth, development, and responses to the environment. ROS production by the RESPIRATORY BURST OXIDASE PROTEIN D (RBOHD) protein was recently shown to be regulated by PHYTOCHROME B (phyB), and phyB was found to be phosphorylated by FERONIA, highlighting the possibility that these three proteins interact to regulate ROS levels during stress. C_LIO_LIImmunoprecipitation and proximity labelling, followed by split-luciferase and functional validation assays, were used to study the interactions between FERONIA, phyB, and RBOHD during excess light (EL) stress in Arabidopsis thaliana. C_LIO_LIWe reveal that phyB and FERONIA interact with RBOHD, that phosphorylation of phyB by FERONIA, as well as the kinase activity of FERONIA, are required for RBOHD-driven ROS production in response to EL stress, and that CYSTEINE-RICH RECEPTOR LIKE KINASE 10 (CRK10) and PLASMA MEMBRANE INTRINSIC PROTEIN 2;6 (PIP2;6) interact with RBOHD and phyB and are also required for EL-driven RBOHD ROS production. C_LIO_LIOur findings uncover the existence of a putative plasma membrane complex between FERONIA, RBOHD, CRK10, and PIP2;6 that interacts with phyB to regulate ROS production in Arabidopsis in response to stress. This complex could play a canonical role in the integration and regulation of multiple signaling pathways in plants. C_LI Plain Language SummaryWe identified a complex between several different proteins at the plasma membrane that interacts with the light and temperature receptor protein phytochrome B to regulate reactive oxygen species formation during stress in plants. This complex could be involved in the regulation and integration of multiple abiotic and biotic signals in plants. tenten

plant biology↗

bioRxiv2025

United we stand: Plants that physically touch each other are more resilient to stress

Plants use sophisticated signaling networks to communicate with each other. While this process is thought to support the overall health and resilience of plant communities, it could also reflect eavesdropping between plants used for competition. Here we reveal that plants that physically touch each other aboveground are more resilient to excess light stress, and that this phenomenon is dependent on the ability of plants to exchange aboveground electric and H2O2 signals with each other. Using a mutant that is unable to transfer Ca2+/reactive oxygen species (ROS) signals but can transfer electric signals (hpca1), as a mediator/connector between different plants, we further separate electric from Ca2+/ROS plant-to-plant signals and transcriptional landscapes, and show that the transfer of Ca2+/ROS signals, as well as the function of several Ca2+/ROS-dependent transcripts, is required for excess light stress acclimation. Our study reveals that plants that live together and physically touch each other establish an aboveground community-wide signaling network that enhances their collective resilience to stress. TeaserPlants that physically touch and exchange aboveground signals with each other are more resilient to excess light stress.

plant biology↗

bioRxiv2023

Propagation of a rapid cell-to-cell H2O2 signal over long distances in a monolayer of cardiomyocyte cells

Cell-to-cell communication plays a cardinal role in the biology of multicellular organisms. H2O2 is an important cell-to-cell signaling molecule involved in the response of mammalian cells to wounding and other stimuli. We previously identified a signaling pathway that transmits wound-induced cell-to-cell H2O2 signals within minutes over long distances, measured in centimeters, in a monolayer of cardiomyocytes. Here we report that this long-distance H2O2 signaling pathway is accompanied by enhanced accumulation of cytosolic H2O2 and altered redox state in cells along its path. We further show that it requires the production of superoxide, as well as the function of gap junctions, and that it is accompanied by changes in the abundance of hundreds of proteins in cells along its path. Our findings highlight the existence of a unique and rapid long-distance H2O2 signaling pathway that could play an important role in different inflammatory responses, wound responses/healing, cardiovascular disease, and/or other conditions. HighlightsO_LIWounding induces an H2O2 cell-to-cell signal in a monolayer of cardiomyocytes. C_LIO_LIThe cell-to-cell signal requires H2O2 and O2{middle dot}- accumulation along its path. C_LIO_LIThe signal propagates over several centimeters changing the redox state of cells. C_LIO_LIChanges in the abundance of hundreds of proteins accompanies the signal. C_LIO_LIThe cell-to-cell signal requires paracrine and juxtacrine signaling. C_LI Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=70 SRC="FIGDIR/small/572374v1_ufig1.gif" ALT="Figure 1"> View larger version (18K): org.highwire.dtl.DTLVardef@3b3806org.highwire.dtl.DTLVardef@1db37fcorg.highwire.dtl.DTLVardef@138bdd7org.highwire.dtl.DTLVardef@377402_HPS_FORMAT_FIGEXP M_FIG C_FIG

cell biology↗

bioRxiv2023

Plant-to-plant reactive oxygen signal transmission via a Cuscuta bridge

Cuscuta, commonly known as dodder, is a parasitic plant that thrives by attaching itself to the stems of other plants. It is found across the globe and is notorious for obstructing crop growth as a weed. Over the past decade, Cuscuta has been used to gain insights into plant-plant interactions and molecular trafficking. Here, we report that two plants connected via a Cuscuta bridge can exchange rapid systemic calcium, electric, and reactive oxygen species signals. These findings suggest that plant interactions with Cuscuta may have beneficial effects to plants, enabling them to rapidly communicate with each other.

plant biology↗

bioRxiv2022

CWLP and PRP940 form plasma-membrane nanodomain complexes with aquaporins, interact with PP2A and contribute to dehydration tolerance

The C-type hybrid-proline-rich protein (HyPRP) AtCWLP and its homolog AtPRP940 are referred as cell wall (CW)-plasma-membrane (PM) linker proteins, but little is known about their functions. Here we show that N-terminal proline-rich domains of CWLP and PRP940, containing glycosylated hydroxyproline residues, contact the CW, while their C-terminal 8CM domains function as PM-scaffolds. Both proteins are detected in PM nanodomains (PM-ND) and show co-localization and co-immunoprecipitation with aquaporins PIP2;1 and PIP2;7. Inhibition of actin polymerization by latrunculin B promotes CWLP-endosome appearance, while blocking the actomyosin-based transport by a truncated form of myosin XI-K relaxes lateral boundaries of CWLP-PIP2;1 PD-NDs. Mass spectrometry data indicate that CWLP co-purifies with dynamins implicated in fission of endocytic PD-ND invaginations. Lack of co-localization and co-immunoprecipitation with aquaporin-binding flotillin (FLOT2) indicates that CWLP and PRP940 mark a new distinct type of PM-ND. Yeast two-hybrid and co-immunoprecipitation assays demonstrate that CWLP and PRP940 interact with multiple aquaporins and several protein phosphatase PP2A-B regulatory subunits. By preventing irreversible separation of CW and PM, and likely assisting PP2A-mediated dephosphorylation of aquaporins and closure of their water channels, overexpression of CWLP confers tolerance to plasmolysis, dehydration and freezing in Arabidopsis and to water shortage in potato plants. Summary StatementArabidopsis Hybrid-Proline-Rich Proteins CWLP and PRP940 occur in association with dynamins, recruit PP2A protein phosphatases to aquaporin water channels in plasma-membrane (PM) nanodomains and elevate tolerance to cellular dehydration.

plant biology↗

bioRxiv2022

ROS are evolutionary conserved cell-to-cell signals

Cell-to-cell communication is fundamental to multicellular organisms and unicellular organisms living in a microbiome. A unique cell-to-cell communication mechanism that uses reactive oxygen species (ROS) as a signal (termed the ROS wave) was recently identified in flowering plants. Here we report that a ROS-mediated cell-to-cell signaling process, like the ROS wave, can be found in ferns, mosses, unicellular algae, amoeba, mammalian cells, and isolated hearts. We further show that this process can be triggered by a localized stress treatment or H2O2 application and blocked by inhibition of NADPH oxidases, and that in unicellular algae, it communicates important stress-response signals between cells. Taken together, our findings suggest that cell-to-cell ROS signaling evolved before unicellular and multicellular organisms diverged. The finding of a ROS wave-like signaling process in mammalian cells further contributes to our understanding of different diseases and could impact the development of new drugs that target cancer or heart disease.

plant biology↗

bioRxiv2022

An interplay between JA and SA modulates rapid systemic ROS signaling during responses to high light stress or wounding

Plants can send long distance cell-to-cell signals from a single tissue subjected to stress to the entire plant. This ability is termed systemic signaling and is essential for plant acclimation to stress and/or defense against pathogens. Several signaling mechanisms are associated with systemic signaling, including the reactive oxygen species (ROS) wave, calcium wave, hydraulic wave, and electric signals. The ROS wave coordinates multiple physiological, molecular, and metabolic responses among different parts of the plant, and is essential for systemic acquired acclimation (SAA) to stress. In addition, it is linked with several plants hormones, including jasmonic acid (JA), salicylic acid (SA), and abscisic acid (ABA). However, how these plant hormones modulate the ROS wave and whether they are required for SAA is not clear. Here we report that SA and JA play antagonistic roles in modulating the ROS wave. While SA augments the ROS wave, JA suppresses it, during responses to a local wounding or high light (HL) stress treatments. We further show that ethylene and ABA are essential for the regulation of the ROS wave during systemic responses to a local wounding treatment. Interestingly, we found that the redox-response protein NONEXPRESSOR OF PATHOGENESIS RELATED PROTEIN 1 (NPR1) is required for systemic ROS accumulation in response to wounding or HL stress, as well as for SAA to HL stress. Taken together, our findings suggests that an interplay between JA and SA could regulate systemic signaling and SAA during responses of plants to abiotic stress or wounding. One sentence summaryAn antagonistic interaction between SA and JA attenuates the accumulation of ROS in local and systemic tissues during responses of plants to light stress or wounding.

plant biology↗

bioRxiv2022

HPCA1 is required for systemic ROS and calcium cell-to-cell signaling and plant acclimation to stress

As multicellular organisms, plants constantly balance and coordinate many metabolic, physiological, and molecular responses between different cell types and tissues. This process is essential for plant development, growth, and response to different environmental cues. Because plants lack a nervous system, they transmit different signals over long distances via cell-to-cell signaling. Recent studies revealed that reactive oxygen species (ROS), produced by respiratory burst oxidase homologs (RBOHs) at the apoplast play a key role in cell-to-cell signaling. A state of enhanced ROS production by one cell is thereby sensed by a neighboring cell, causing it to produce ROS, creating a continuous chain of cell-to-cell ROS accumulation termed the ROS wave. This process was found to mediate systemic signals throughout the plant and is required for plant acclimation to different stresses. Although RBOHs were found to produce ROS essential for this process, the identity of the receptor(s) perceiving the apoplastic ROS signal is currently unknow. Here we reveal that the leucine-rich-repeat receptor-like kinase HPCA1 (H2O2-induced Ca2+ increases 1) acts as a central ROS receptor required for the propagation of cell-to-cell ROS signals, systemic signaling in response to different biotic and abiotic stresses, and plant acclimation to stress. We further report that HPCA1 is required for systemic calcium signals, but not systemic membrane depolarization responses, and identify key calcium-dependent signal transduction proteins involved in this process. Our findings reveal that HPCA1 plays a key role in mediating and coordinating systemic cell-to-cell ROS and calcium signals that are required for plant acclimation to stress.

plant biology↗

bioRxiv2022

Extracellular ATP plays an important role in systemic wound response activation

Mechanical wounding occurs in plants during biotic (e.g., herbivore or pathogen attack) or abiotic (e.g., wind damage or freezing) stresses and is associated with the activation of multiple signaling pathways. These initiate many wound responses at the wounded tissues, as well as trigger long-distance signaling pathways that activate wound responses in tissues that were not affected by the initial wounding event (termed systemic wound response). Among the different systemic signals activated by wounding are electric signals, calcium and reactive oxygen species (ROS) waves, and different plant hormones such as jasmonic acid. The release of glutamate from cells at the wounded tissues was recently proposed to trigger several different systemic signal transduction pathways via glutamate-like receptors (GLRs). However, the role of another important compound released from cells during wounding (i.e., extracellular ATP; eATP) in triggering systemic responses is not clear. Here we show that eATP that accumulates in wounded leaves and is sensed by the purinoreceptor kinase P2K is required for the activation of the ROS wave during wounding. Application of eATP to unwounded leaves triggered the ROS wave, and the activation of the ROS wave by wounding or eATP application was suppressed in mutants deficient in P2K (i.e., p2k1-3, p2k2, and p2k1-3p2k2). In addition, the expression of several systemic wound response transcripts was suppressed in mutants deficient in P2K during wounding. Our findings reveal that in addition to sensing glutamate via GLRs, eATP sensed by P2Ks is playing a key role in the triggering of systemic wound responses in plants. One sentence summaryExtracellular ATP plays an important role in triggering the ROS wave and systemic transcriptomics responses during wounding.

plant biology↗

bioRxiv2021

Differential regulation of flower transpiration during abiotic stress in plants

Heat waves, occurring during droughts, can have a devastating impact on yield, especially if they happen during the flowering and seed set stages of the crop cycle. Global warming and climate change are driving an alarming increase in the frequency and intensity of combined drought and heat stress episodes, critically threatening global food security. Previous studies revealed that during a combination of drought and heat stress stomata on leaves of many plants are closed, preventing cooling by transpiration. Because high temperature is detrimental to reproductive processes, essential for plant yield, we measured the inner temperature, transpiration, and sepal stomatal aperture of closed soybean flowers, developing on plants subjected to a combination of drought and heat stress. Here, we report that during a combination of drought and heat stress soybean plants prioritize transpiration through flowers over transpiration through leaves by opening their flower stomata, while keeping their leaf stomata closed. This acclimation strategy, termed differential transpiration, lowers flower inner temperature by about 2-3{degrees}C, protecting reproductive processes at the expense of vegetative tissues. Manipulating stomatal regulation, stomatal size and/or stomatal density of flowers could therefore serve as a viable strategy to enhance the yield of different crops and mitigate some of the current and future impacts of global warming and climate change on agriculture. One sentence summaryDuring stress conditions that result in higher flower inner temperature plants use a differential transpiration strategy to protect reproductive processes at the expense of vegetative tissues.

plant biology↗

bioRxiv2021

Phytochrome B regulates reactive oxygen signaling during abiotic and biotic stress in plants

Plants are essential for life on Earth converting light into chemical energy in the form of sugars. To adjust for changes in light intensity and quality, and to become as efficient as possible in harnessing light, plants utilize multiple light receptors, signaling, and acclimation mechanisms. In addition to altering plant metabolism, development and growth, light cues sensed by some photoreceptors, such as phytochromes, impact on many plant responses to biotic and abiotic stresses. Central for plant responses to different stresses are reactive oxygen species (ROS) that function as key signaling molecules. Recent studies demonstrated that respiratory burst oxidase homolog (RBOH) proteins that reside at the plasma membrane and produce ROS at the apoplast play a key role in plant responses to different biotic and abiotic stresses. Here we reveal that phytochrome B (phyB) and RBOHs function as part of a key regulatory module that controls ROS production, transcript expression, and plant acclimation to excess light stress. We further show that phyB can regulate ROS production during stress even if it is restricted to the cytosol, and that phyB, RBOHD and RBOHF co-regulate thousands of transcripts in response to light stress. Surprisingly, we found that phyB is also required for ROS accumulation in response to heat, wounding, cold, and bacterial infection. Taken together, our findings reveal that phyB plays a canonical role in plant responses to biotic and abiotic stresses, regulating ROS production, and that phyB and RBOHs function in the same pathway. Significant StatementAbiotic and biotic stresses cause extensive losses to agricultural production and threaten global food security. Augmenting plant resilience to stressful conditions requires understanding of how plants sense stress. Here we report that the sensing of different abiotic and biotic stresses that result in the production of the key stress-response signaling molecules, reactive oxygen species, requires the plant photoreceptor protein phytochrome B. We further show that in contrast to its many nuclear functions, phytochrome B regulates reactive oxygen production by plasma membrane-localized respiratory burst oxidase homologs while localized to the cytosol. Our findings reveal the existence of a rapid stress response regulatory mechanism requiring phytochrome B and reactive oxygen species, essential for plant acclimation to stress.

plant biology↗

bioRxiv2021

Integration of electric, calcium, reactive oxygen species and hydraulic signals during rapid systemic signaling in plants

The sensing of abiotic stress, mechanical injury, or pathogen attack by a single plant tissue results in the activation of systemic signals that travel from the affected tissue to the entire plant, alerting it of an impending stress or pathogen attack. This process is essential for plant survival during stress and is termed systemic signaling. Among the different signals triggered during this process are calcium, electric, reactive oxygen species (ROS) and hydraulic signals. These are thought to propagate at rapid rates through the plant vascular bundles and to regulate many of the systemic processes essential for plant survival. Although the different signals activated during systemic signaling are thought to be interlinked, their coordination and hierarchy remain to be determined. Here, using a combination of advanced whole-plant imaging and hydraulic pressure measurements, we studied the activation of all four systemic signals in wild type and different Arabidopsis thaliana mutants subjected to a local high light (HL) stress or wounding. Our findings reveal that in response to wounding systemic changes in membrane potential, calcium, ROS, and hydraulic pressure are coordinated by glutamate receptor-like (GLR) proteins 3.3 and 3.6, while in response to HL the respiratory burst oxidase homolog D-driven systemic ROS signal could be separated from systemic changes in membrane potential and calcium levels. We further determine that plasmodesmata functions are required for systemic changes in membrane potential, calcium, and ROS during systemic signaling. Our findings shed new light on the different mechanisms that integrate different systemic signals in plants during stress. Significance statementThe ability of plants to transmit a signal from a stressed or wounded tissue to the entire plant, termed systemic signaling, is key to plant survival during conditions of environmental stress. At least four different systemic signals are thought to be involved in this process: electric, calcium, reactive oxygen and hydraulic. However, how are they coordinated and whether they can be stress-specific is mostly unknown. Here we report that different types of stimuli can induce different types of systemic signals that may or may not be linked with each other. We further reveal that hydraulic waves can be actively regulated in plants in response to wounding, and that proteins that regulate plasmodesmata pores play a key role in systemic signaling.

plant biology↗

bioRxiv2020

A systemic whole-plant change in redox levels accompanies the rapid systemic response of Arabidopsis to wounding

Reactive oxygen species (ROS) play a key role in regulating plant responses to different abiotic stresses, wounding and pathogen attack. In addition to triggering responses at the tissues directly subjected to stress, ROS were recently shown to mediate a rapid whole-plant systemic signal, termed the "ROS wave", required for inducing a state of systemic acquired acclimation, or systemic wound response. However, whether the ROS wave that spreads from the local tissues subjected to wounding to the rest of the plant triggers alterations in redox levels, is mostly unknown at present. Here, using a genetically-encoded reporter for cellular glutathione redox changes, roGFP1, we show that the wounding-induced systemic ROS wave in Arabidopsis thaliana is accompanied by a rapid systemic wave of cytosolic redox oxidation, termed a "redox wave". The ROS wave may therefore trigger changes in redox levels in systemic leaves that in turn can trigger transcriptional, metabolic and proteomic changes resulting in acclimation and/or systemic wound responses. One sentence summaryThe wounding-induced reactive oxygen species (ROS) wave is accompanied by a systemic whole-plant redox response.

plant biology↗

bioRxiv2020

Plasmodesmata-localized proteins and reactive oxygen species orchestrate light-induced rapid systemic signaling in Arabidopsis

Systemic signaling and systemic acquired acclimation (SAA) are key to the survival of plants during episodes of abiotic stress. These processes depend on a continuous chain of cell-to-cell signaling events that extends from the initial tissue that senses the stress (local tissue) to the entire plant (systemic tissues). Among the different systemic signaling molecules and processes thought to be involved in this cell-to-cell signaling mechanism are reactive oxygen species (ROS), calcium, electric and hydraulic signals. How these different signals and processes are interlinked, and how they transmit the systemic signal all the way from the local tissue to the entire plant, remain however largely unknown. Here, studying the systemic response of Arabidopsis thaliana to a local treatment of excess light stress, we report that respiratory burst oxidase homolog D (RBOHD)-generated ROS enhance cell-to-cell transport and plasmodesmata (PD) pore size in a process that depends on the function of PD-localized proteins (PDLPs) 1 and 5, promoting the cell-to-cell transport of systemic signals during responses to light stress. We further identify aquaporins, and several different calcium-permeable channels, belonging to the glutamate receptor-like, mechanosensitive small conductance-like, and cyclic nucleotide-gated families, as involved in this process, but determine that their function is primarily required for the maintenance of the signal in each cell along the path of the systemic signal, as well as for the establishment of acclimation at the local and systemic tissues. PD and RBOHD-generated ROS orchestrate therefore light stress-induced rapid cell-to-cell spread of systemic signals in Arabidopsis. One-sentence summaryRespiratory burst oxidase homolog D-generated reactive oxygen species enhance cell-to-cell transport and plasmodesmata (PD) pore size in a process that depends on the function of the PD-localized proteins (PDLPs) 1 and 5, promoting the cell-to-cell transport of rapid systemic signals during the response of Arabidopsis to excess light stress.

plant biology↗

bioRxiv2020

The impact of water deficit and heat stress combination on the molecular response, physiology and seed production of soybean

A combination of drought and heat stress, occurring at the vegetative or reproductive growth phase of many different crops, can have a devastating impact on yield. In soybean (Glycine max), a considerable effort has been made to develop genotypes with enhanced yield production under conditions of drought or heat stress. However, how these genotypes perform in terms of growth, physiological responses and most importantly seed production, under conditions of drought and heat combination is mostly unknown. Here, we studied the impact of water deficit and heat stress combination on the physiology, seed production and yield per plant of two soybean genotypes, Magellan and Plant Introduction (PI) 548313, that differ in their reproductive responses to heat stress. Our findings reveal that although PI 548313 produced more seeds than Magellan under conditions of heat stress, under conditions of water deficit and heat stress combination its seed production decreased. Because number of flowers and pollen germination of PI 548313 remained high under heat or water deficit and heat combination, the reduced seed production exhibited by PI 548313 under the stress combination could be a result of processes that occur at the stigma, ovaries and/or other parts of the flower following pollen germination. HighlightTolerance to heat stress was found not to confer tolerance to a combination of water deficit and heat stress in soybean, highlighting the need for breeding strategies targeting the stress combination.

plant biology↗