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František Baluška - One of the best experts on this subject based on the ideXlab platform.
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Root-Apex Proton Fluxes at the Centre of Soil-Stress Acclimation
Trends in plant science, 2020Co-Authors: Wei Siao, František Baluška, Devrim Coskun, Herbert J. KronzuckerAbstract:Proton (H+) fluxes in plant Roots play critical roles in maintaining Root growth and facilitating plant responses to multiple soil stresses, including fluctuations in nutrient supply, salt infiltration, and water stress. Soil mining for nutrients and water, rates of nutrient uptake, and the modulation of cell expansion all depend on the regulation of Root H+ fluxes, particularly at the Root Apex, mediated primarily by the activity of plasma membrane (PM) H+-ATPases. Here, we summarize recent findings on the regulatory mechanisms of H+ fluxes at the Root Apex under three abiotic stress conditions – phosphate deficiency, salinity stress, and water deficiency – and present an integrated physiomolecular view of the functions of H+ fluxes in maintaining Root growth in the acclimation to soil stress.
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immunogold em analysis reveal brefeldin a sensitive clusters of auxin in arabidopsis Root Apex cells
Communicative & Integrative Biology, 2017Co-Authors: U Mettbach, Stefano Mancuso, Miroslav Strnad, František BaluškaAbstract:Immunogold electron microscopy (EM) study of Arabidopsis Root apices analyzed using specific IAA antibody and high-pressure freeze fixation technique allowed, for the first time, vizualization of subcellular localization of IAA in cells assembled intactly within plant tissues. Our quantitative analysis reveals that there is considerable portion of IAA gold particles that clusters within vesicles and membraneous compartments in all Root Apex cells. There are clear tissue-specific and developmental differences of clustered IAA in Root apices. These findings have significant consequences for our understanding of this small molecule which is controlling plant growth, development and behavior.
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Root cap-dependent gravitropic U-turn of maize Root requires light-induced auxin biosynthesis via the YUC pathway in the Root Apex
Journal of experimental botany, 2016Co-Authors: Hiromi Suzuki, Ken Yokawa, František Baluška, Sayuri Nakano, Yuriko Yoshida, Isabelle Fabrissin, Takashi Okamoto, Tomokazu KoshibaAbstract:Gravitropism refers to the growth or movement of plants that is influenced by gravity. Roots exhibit positive gravitropism, and the Root cap is thought to be the gravity-sensing site. In some plants, the Root cap requires light irradiation for positive gravitropic responses. However, the mechanisms regulating this phenomenon are unknown. We herein report that maize Roots exposed to white light continuously for ≥1-2h show increased indole-3-acetic acid (IAA) levels in the Root tips, especially in the transition zone (1-3mm from the tip). Treatment with IAA biosynthesis inhibitors yucasin and l-kynurenine prevented any increases in IAA content and Root curvature under light conditions. Analyses of the incorporation of a stable isotope label from tryptophan into IAA revealed that some of the IAA in Roots was synthesized in the Root Apex. Furthermore, Zmvt2 and Zmyuc gene transcripts were detected in the Root Apex. One of the Zmyuc genes (ZM2G141383) was up-regulated by light irradiation in the 0-1mm tip region. Our findings suggest that IAA accumulation in the transition zone is due to light-induced activation of Zmyuc gene expression in the 0-1mm Root Apex region. Light-induced changes in IAA levels and distributions mediate the maize Root gravitropic U-turn.
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MES Buffer Affects Arabidopsis Root Apex Zonation and Root Growth by Suppressing Superoxide Generation in Root Apex.
Frontiers in plant science, 2016Co-Authors: Tomoko Kagenishi, Ken Yokawa, František BaluškaAbstract:In plants, growth of Roots and Root hairs is regulated by the fine cellular control of pH and reactive oxygen species. MES, 2-(N-morpholino)ethanesulfonic acid as one of the Good’s buffers has broadly been used for buffering medium, and it is thought to suit for plant growth with the concentration at 0.1% (w/v) because the buffer capacity of MES ranging pH 5.5-7.0 (for Arabidopsis, pH 5.8). However, many reports have shown that, in nature, Roots require different pH values on the surface of specific Root Apex zones, namely meristem, transition zone and elongation zone. Despite the fact that Roots always grow on a media containing buffer molecule, little is known about impact of MES on Root growth. Here, we have checked the effects of different concentrations of MES buffer using growing Roots of Arabidopsis thaliana. Our results show that 1% of MES significantly inhibited Root growth, the number of Root hairs and length of meristem, whereas 0.1% promoted Root growth and Root Apex area (region spanning from the Root tip up to the transition zone). Furthermore, superoxide generation in Root Apex disappeared at 1% of MES. These results suggest that MES disturbs normal Root morphogenesis by changing the reactive oxygen species (ROS) homeostasis in Root Apex.
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Nitric Oxide-Mediated Maize Root Apex Responses to Nitrate are Regulated by Auxin and Strigolactones
Frontiers in plant science, 2016Co-Authors: Alessandro Manoli, Ken Yokawa, František Baluška, Sara Trevisan, Boris Voigt, Silvia QuaggiottiAbstract:Nitrate (NO3-) is a key element for crop production but its levels in agricultural soils are limited. Plants have developed mechanisms to cope with these NO3- fluctuations based on sensing nitrate at the Root Apex. Particularly, the transition zone (TZ) of Root Apex has been suggested as a signalling-response zone. This study dissects cellular and molecular mechanisms underlying NO3- resupply effects on primary Root growth in maize, confirming nitric oxide (NO) as a putative modulator. Nitrate restoration induced primary Root elongation within the first 2 h, corresponding to a stimulation of cell elongation at the basal border of the TZ. Xyloglucans (XGs) immunolocalization together with Brefeldin A applications demonstrated that nitrate resupply induces XG accumulation. This effect was blocked by cPTIO (NO scavenger). Transcriptional analysis of ZmXET1 confirmed the stimulatory effect of nitrate on XGs accumulation in cells of the TZ. Immunolocalization analyses revealed a positive effect of nitrate resupply on auxin and PIN1 accumulation, but a transcriptional regulation of auxin biosynthesis/transport/signalling genes was excluded. Short-term nitrate treatment repressed the transcription of genes involved in strigolactones (SLs) biosynthesis and transport, mainly in the TZ. Enhancement of carotenoid cleavage dioxygenases (CCDs) transcription in presence of cPTIO indicated endogenous NO as a negative modulator of CCDs activity. Finally, treatment with the SLs-biosynthesis inhibitor (TIS108) restored the Root growth in the nitrate-starved seedlings. Present report suggests that the NO-mediated Root Apex responses to nitrate are accomplished in cells of the TZ via integrative actions of auxin, NO and SLs.
Stefano Mancuso - One of the best experts on this subject based on the ideXlab platform.
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immunogold em analysis reveal brefeldin a sensitive clusters of auxin in arabidopsis Root Apex cells
Communicative & Integrative Biology, 2017Co-Authors: U Mettbach, Stefano Mancuso, Miroslav Strnad, František BaluškaAbstract:Immunogold electron microscopy (EM) study of Arabidopsis Root apices analyzed using specific IAA antibody and high-pressure freeze fixation technique allowed, for the first time, vizualization of subcellular localization of IAA in cells assembled intactly within plant tissues. Our quantitative analysis reveals that there is considerable portion of IAA gold particles that clusters within vesicles and membraneous compartments in all Root Apex cells. There are clear tissue-specific and developmental differences of clustered IAA in Root apices. These findings have significant consequences for our understanding of this small molecule which is controlling plant growth, development and behavior.
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The Electrical Network of Maize Root Apex is Gravity Dependent
Scientific reports, 2015Co-Authors: Elisa Masi, František Baluška, Sergio Mugnai, Elisa Azzarello, Marzena Ciszak, Camilla Pandolfi, Diego Comparini, Emanuela Monetti, Stefano MancusoAbstract:Investigations carried out on maize Roots under microgravity and hypergravity revealed that gravity conditions have strong effects on the network of plant electrical activity. Both the duration of action potentials (APs) and their propagation velocities were significantly affected by gravity. Similarly to what was reported for animals, increased gravity forces speed-up APs and enhance synchronized electrical events also in plants. The Root Apex transition zone emerges as the most active, as well as the most sensitive, Root region in this respect.
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Root Apex Transition Zone As Oscillatory Zone
Frontiers in plant science, 2013Co-Authors: František Baluška, Stefano MancusoAbstract:Root Apex of higher plants shows very high sensitivity to environmental stimuli. The Root cap acts as the most prominent plant sensory organ; sensing diverse physical parameters such as gravity, light, humidity, oxygen and critical inorganic nutrients. However, the motoric responses to these stimuli are accomplished in the elongation region. This spatial discrepancy was solved when we have discovered and characterized the transition zone which is interpolated between the apical meristem and the subapical elongation zone. Cells of this zone are very active in the cytoskeletal rearrangements, endocytosis and endocytic vesicle recycling, as well as in electric activities. Here we discuss the oscillatory nature of the transition zone which, together with several other features of this zone, suggest that it acts as some kind of command centre. In accordance with the early proposal of Charles and Francis Darwins, cells of this Root zone receive sensory information from the Root cap and instruct the motoric responses of cells in the elongation zone.
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Local Root Apex hypoxia induces NO-mediated hypoxic acclimation of the entire Root.
Plant & cell physiology, 2012Co-Authors: Sergio Mugnai, František Baluška, Elisa Azzarello, Stefano MancusoAbstract:Roots are very sensitive to hypoxia and adapt effectively to a reduced availability of oxygen in the soil. However, the site of the Root where oxygen availability is sensed and how Roots acclimate to hypoxia remain unclear. In this study, we found that the Root Apex transition zone plays central roles in both sensing and adapting to Root hypoxia. The exposure of cells of the Root Apex to hypoxia is sufficient to achieve hypoxic acclimation of the entire Root; particularly relevant in this respect is that, of the entire Root Apex, the transition zone cells show the highest demand for oxygen and also emit the largest amount of nitric oxide (NO). Local Root Apex-specific oxygen deprivation dramatically inhibits the oxygen influx peak in the transition zone and simultaneously stimulates a local increase in NO emission. The hypoxia-induced efflux of NO is strictly associated with the transition zone and is essential for hypoxic acclimation of the entire Root.
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Root Apex transition zone a signalling response nexus in the Root
Trends in Plant Science, 2010Co-Authors: František Baluška, Stefano Mancuso, Dieter Volkmann, Peter W. BarlowAbstract:Longitudinal zonation, as well as a simple and regular anatomy, are hallmarks of the Root Apex. Here we focus on one particular Root-Apex zone, the transition zone, which is located between the apical meristem and basal elongation region. This zone has a unique role as the determiner of cell fate and Root growth; this is accomplished by means of the complex system of a polar auxin transport circuit. The transition zone also integrates diverse inputs from endogenous (hormonal) and exogenous (sensorial) stimuli and translates them into signalling and motoric outputs as adaptive differential growth responses. These underlie the Root-Apex tropisms and other aspects of adaptive Root behaviour.
Peter W. Barlow - One of the best experts on this subject based on the ideXlab platform.
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Root Apex transition zone a signalling response nexus in the Root
Trends in Plant Science, 2010Co-Authors: František Baluška, Stefano Mancuso, Dieter Volkmann, Peter W. BarlowAbstract:Longitudinal zonation, as well as a simple and regular anatomy, are hallmarks of the Root Apex. Here we focus on one particular Root-Apex zone, the transition zone, which is located between the apical meristem and basal elongation region. This zone has a unique role as the determiner of cell fate and Root growth; this is accomplished by means of the complex system of a polar auxin transport circuit. The transition zone also integrates diverse inputs from endogenous (hormonal) and exogenous (sensorial) stimuli and translates them into signalling and motoric outputs as adaptive differential growth responses. These underlie the Root-Apex tropisms and other aspects of adaptive Root behaviour.
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Root Apex transition zone: a signalling–response nexus in the Root
Trends in plant science, 2010Co-Authors: František Baluška, Stefano Mancuso, Dieter Volkmann, Peter W. BarlowAbstract:Longitudinal zonation, as well as a simple and regular anatomy, are hallmarks of the Root Apex. Here we focus on one particular Root-Apex zone, the transition zone, which is located between the apical meristem and basal elongation region. This zone has a unique role as the determiner of cell fate and Root growth; this is accomplished by means of the complex system of a polar auxin transport circuit. The transition zone also integrates diverse inputs from endogenous (hormonal) and exogenous (sensorial) stimuli and translates them into signalling and motoric outputs as adaptive differential growth responses. These underlie the Root-Apex tropisms and other aspects of adaptive Root behaviour.
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Structure and function at the Root Apex - phylogenetic and ontogenetic perspectives on apical cells and quiescent centres
Plant and Soil, 1994Co-Authors: Peter W. BarlowAbstract:The summit of Roots of various plant species may be occupied by a single, rapidly proliferating tetrahedral apical cell (as in ferns), or by a multicellular and slowly proliferating quiescent centre (as in angiosperms), or by intermediate types of cellular organizations. The present paper attempts to deduce the phylogeny of these various types of cellular patterning at the Root Apex.
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Molecular characterization of cell populations in the maize Root Apex
Molecular and Cell Biology of the Plant Cell Cycle, 1993Co-Authors: Paolo A. Sabelli, S. R. Burgess, Jesus V. Carbajosa, J. S. Parker, Nigel G. Halford, Peter R. Shewry, Peter W. BarlowAbstract:Several features make the Root Apex of maize (Zea mays L.) a good experimental system for studying cell cycle controls in relation to development in higher plants. Actively dividing meristematic cells, slowly-cycling quiescent centre cells, differentiating cap cells and senescent detaching cap cells are distinctively compartmented. In addition, the quiescent centre can be activated into rapid proliferation in response to stresses. Although there is a wealth of cytological and physiological information about the behaviour of cells in the Root Apex, very little is known about the molecular factors which control the patterns of cell division and differentiation. Differential screening of cDNA libraries obtained from discrete cell populations from the Apex may provide a means to identify genes which are expressed in cell cycle- and differentiation-dependent manners.
Dieter Volkmann - One of the best experts on this subject based on the ideXlab platform.
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Root Apex transition zone a signalling response nexus in the Root
Trends in Plant Science, 2010Co-Authors: František Baluška, Stefano Mancuso, Dieter Volkmann, Peter W. BarlowAbstract:Longitudinal zonation, as well as a simple and regular anatomy, are hallmarks of the Root Apex. Here we focus on one particular Root-Apex zone, the transition zone, which is located between the apical meristem and basal elongation region. This zone has a unique role as the determiner of cell fate and Root growth; this is accomplished by means of the complex system of a polar auxin transport circuit. The transition zone also integrates diverse inputs from endogenous (hormonal) and exogenous (sensorial) stimuli and translates them into signalling and motoric outputs as adaptive differential growth responses. These underlie the Root-Apex tropisms and other aspects of adaptive Root behaviour.
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Root Apex transition zone: a signalling–response nexus in the Root
Trends in plant science, 2010Co-Authors: František Baluška, Stefano Mancuso, Dieter Volkmann, Peter W. BarlowAbstract:Longitudinal zonation, as well as a simple and regular anatomy, are hallmarks of the Root Apex. Here we focus on one particular Root-Apex zone, the transition zone, which is located between the apical meristem and basal elongation region. This zone has a unique role as the determiner of cell fate and Root growth; this is accomplished by means of the complex system of a polar auxin transport circuit. The transition zone also integrates diverse inputs from endogenous (hormonal) and exogenous (sensorial) stimuli and translates them into signalling and motoric outputs as adaptive differential growth responses. These underlie the Root-Apex tropisms and other aspects of adaptive Root behaviour.
Herbert J. Kronzucker - One of the best experts on this subject based on the ideXlab platform.
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Root-Apex Proton Fluxes at the Centre of Soil-Stress Acclimation
Trends in plant science, 2020Co-Authors: Wei Siao, František Baluška, Devrim Coskun, Herbert J. KronzuckerAbstract:Proton (H+) fluxes in plant Roots play critical roles in maintaining Root growth and facilitating plant responses to multiple soil stresses, including fluctuations in nutrient supply, salt infiltration, and water stress. Soil mining for nutrients and water, rates of nutrient uptake, and the modulation of cell expansion all depend on the regulation of Root H+ fluxes, particularly at the Root Apex, mediated primarily by the activity of plasma membrane (PM) H+-ATPases. Here, we summarize recent findings on the regulatory mechanisms of H+ fluxes at the Root Apex under three abiotic stress conditions – phosphate deficiency, salinity stress, and water deficiency – and present an integrated physiomolecular view of the functions of H+ fluxes in maintaining Root growth in the acclimation to soil stress.
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The Response of the Root Apex in Plant Adaptation to Iron Heterogeneity in Soil.
Frontiers in plant science, 2016Co-Authors: Herbert J. Kronzucker, Weiming ShiAbstract:Iron (Fe) is an essential micronutrient for plant growth and development, and is frequently limiting. By contrast, over-accumulation of iron in plant tissues leads to toxicity. In soils, the distribution of Fe is highly heterogeneous. To cope with this heterogeneity, plant Roots engage an array of adaptive responses to adjust their morphology and physiology. In this article, we review Root morphological and physiological changes in response to low- and high-Fe conditions and highlight differences between these responses. We especially focus on the role of the Root Apex in dealing with the stresses resulting from Fe shortage and excess.
