The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Marja C P Timmermans - One of the best experts on this subject based on the ideXlab platform.
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spatiotemporal developmental trajectories in the arabidopsis Root revealed using high throughput single Cell rna sequencing
Developmental Cell, 2019Co-Authors: Tom Denyer, Simon Klesen, Emanuele Scacchi, Kay Nieselt, Marja C P TimmermansAbstract:High-throughput single-Cell RNA sequencing (scRNA-seq) is becoming a cornerstone of developmental research, providing unprecedented power in understanding dynamic processes. Here, we present a high-resolution scRNA-seq expression atlas of the Arabidopsis Root composed of thousands of independently profiled Cells. This atlas provides detailed spatiotemporal information, identifying defining expression features for all major Cell types, including the scarce Cells of the quiescent center. These reveal key developmental regulators and downstream genes that translate Cell fate into distinctive Cell shapes and functions. Developmental trajectories derived from pseudotime analysis depict a finely resolved cascade of Cell progressions from the niche through differentiation that are supported by mirroring expression waves of highly interconnected transcription factors. This study demonstrates the power of applying scRNA-seq to plants and provides an unparalleled spatiotemporal perspective of Root Cell differentiation.
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spatiotemporal developmental trajectories in the arabidopsis Root revealed using high throughput single Cell rna sequencing
Social Science Research Network, 2018Co-Authors: Tom Denyer, Simon Klesen, Emanuele Scacchi, Kay Nieselt, Marja C P TimmermansAbstract:High-throughput single Cell RNA-sequencing (scRNA-seq) is becoming a cornerstone of developmental research, providing unprecedented power in understanding dynamic processes. Here, we present a high-resolution scRNA-seq expression atlas of the Arabidopsis Root, composed of thousands of independently profiled Cells. This atlas provides precise spatiotemporal information, identifying defining expression features for all major Cell types, including the scarce Cells of the quiescent centre. These reveal new developmental regulators and downstream genes that translate Cell fate into distinctive Cell shapes and functions. Developmental trajectories derived from pseudotime analysis depict a finely resolved cascade of Cell progressions from the niche through differentiation that are supported by mirroring expression waves of highly interconnected transcription factors. This study demonstrates the power of applying scRNA-seq to plants, and provides a unique spatiotemporal perspective of Root Cell differentiation.
Leon V Kochian - One of the best experts on this subject based on the ideXlab platform.
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natural variation underlies alterations in nramp aluminum transporter nrat1 expression and function that play a key role in rice aluminum tolerance
Proceedings of the National Academy of Sciences of the United States of America, 2014Co-Authors: Jiping Liu, Dekun Dong, Xiaomin Jia, Susan R Mccouch, Leon V KochianAbstract:Aluminum (Al) toxicity is a major constraint for crop production on acid soils which compose ∼40% of arable land in the tropics and subtropics. Rice is the most Al-tolerant cereal crop and offers a good model for identifying Al tolerance genes and mechanisms. Here we investigated natural variation in the rice Nramp aluminum transporter (NRAT1) gene encoding a Root plasma membrane Al uptake transporter previously hypothesized to underlie a unique Al tolerance mechanism. DNA sequence variation in the NRAT1 coding and regulatory regions was associated with changes in NRAT1 expression and NRAT1 Al transport properties. These sequence changes resulted in significant differences in Al tolerance that were found to be associated with changes in the Al content of Root Cell wall and Cell sap in 24 representative rice lines from a rice association panel. Expression of the tolerant OsNRAT1 allele in yeast resulted in higher Al uptake than did the sensitive allele and conferred greater Al tolerance when expressed in transgenic Arabidopsis. These findings indicate that NRAT1 plays an important role in rice Al tolerance by reducing the level of toxic Al in the Root Cell wall and transporting Al into the Root Cell, where it is ultimately sequestered in the vacuole. Given its ability to enhance Al tolerance in rice and Arabidopsis, this work suggests that the NRAT1 gene or its orthologs may be useful tools for enhancing Al tolerance in a wide range of plant species.
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the role of iron deficiency stress responses in stimulating heavy metal transport in plants
Plant Physiology, 1998Co-Authors: Clara K Cohen, Tama C Fox, David F. Garvin, Leon V KochianAbstract:Plant accumulation of Fe and other metals can be enhanced under Fe deficiency. We investigated the influence of Fe status on heavy-metal and divalent-cation uptake in Roots of pea ( Pisum sativum L. cv Sparkle) seedlings using Cd 2+ uptake as a model system. Radiotracer techniques were used to quantify unidirectional 109 Cd influx into Roots of Fe-deficient and Fe-sufficient pea seedlings. The concentration-dependent kinetics for 109 Cd influx were graphically complex and nonsaturating but could be resolved into a linear component and a saturable component exhibiting Michaelis-Menten kinetics. We demonstrated that the linear component was apoplastically bound Cd 2+ remaining in the Root Cell wall after desorption, whereas the saturable component was transporter-mediated Cd 2+ influx across the Root-Cell plasma membrane. The Cd 2+ transport system in Roots of both Fe-deficient and Fe-sufficient seedlings exhibited similar Michaelis constant values, 1.5 and 0.6 μm, respectively, for saturable Cd 2+ influx, whereas the maximum initial velocity for Cd 2+ uptake in Fe-deficient seedlings was nearly 7-fold higher than that in Fe-grown seedlings. Investigations into the mechanistic basis for this response demonstrated that Fe-deficiency-induced stimulation of the plasma membrane H + -ATPase did not play a role in the enhanced Cd 2+ uptake. Expression studies with the Fe 2+ transporter cloned from Arabidopsis, IRT1, indicated that Fe deficiency induced the expression of this transporter, which might facilitate the transport of heavy-metal divalent cations such as Cd 2+ and Zn 2+ , in addition to Fe 2+ .
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Physiological Characterization of Root Zn2+ Absorption and Translocation to Shoots in Zn Hyperaccumulator and Nonaccumulator Species of Thlaspi
Plant physiology, 1996Co-Authors: Mitch M Lasat, Alan J. M. Baker, Leon V KochianAbstract:Radiotracer techniques were employed to characterize 65Zn2+ influx into the Root symplasm and translocation to the shoot in Thlaspi caerulescens, a Zn hyperaccumulator, and Thlaspi arvense, a nonaccumulator. A protocol was developed that allowed us to quantify unidirectional 65Zn2+ influx across the Root-Cell plasma membrane (20 min of radioactive uptake followed by 15 min of desorption in a 100 [mu]M ZnCl2 + 5 mM CaCl2 solution). Concentration-dependent Zn2+ influx in both Thlaspi species yielded nonsaturating kinetic curves that could be resolved into linear and saturable components. The linear kinetic component was shown to be Cell-wall-bound Zn2+ remaining in the Root after desorption, and the saturable component was due to Zn2+ influx across the Root-Cell plasma membrane. This saturable component followed Michaelis-Menten kinetics, with similar apparent Michaelis constant values for T. caerulescens and T. arvense (8 and 6 [mu]M, respectively). However, the maximum initial velocity for Zn2+ influx in T. caerulescens Root Cells was 4.5-fold higher than for T. arvense, indicating that enhanced absorption into the Root is one of the mechanisms involved in Zn hyperaccumulation. After 96 h 10-fold more 65Zn was translocated to the shoot of T. caerulescens compared with T. arvense. This indicates that transport sites other than entry into the Root symplasm are also stimulated in T. caerulescens. We suggest that although increased Root Zn2+ influx is a significant component, transport across the plasma membrane and tonoplast of leaf Cells must also be critical sites for Zn hyperaccumulation in T. caerulescens.
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induction of iron iii and copper ii reduction in pea pisum sativum l Roots by fe and cu status does the Root Cell plasmalemma fe iii chelate reductase perform a general role in regulating cation uptake
Planta, 1993Co-Authors: Ross M Welch, Wendell A Norvell, Stephen C Schaefer, Jon E Shaff, Leon V KochianAbstract:We investigated the effects of Fe and Cu status of pea (Pisum sativum L.) seedlings on the regulation of the putative Root plasma-membrane Fe(III)-chelate reductase that is involved in Fe(III)-chelate reduction and Fe2+ absorption in dicotyledons and nongraminaceous monocotyledons. Additionally, we investigated the ability of this reductase system to reduce Cu(II)-chelates as well as Fe(III)-chelates. Pea seedlings were grown in full nutrient solutions under control, -Fe, and -Cu conditions for up to 18 d. Iron(III) and Cu(II) reductase activity was visualized by placing Roots in an agarose gel containing either Fe(III)-EDTA and the Fe(II) chelate, Na2bathophenanthrolinedisulfonic acid (BPDS), for Fe(III) reduction, or CuSO4, Na3citrate, and Na2-2,9-dimethyl-4,7-diphenyl-1, 10-phenanthrolinedisulfonic acid (BCDS) for Cu(II) reduction. Rates of Root Fe(III) and Cu(II) reduction were determined via spectrophotometric assay of the Fe(II)-BPDS or the Cu(I)-BCDS chromophore. Reductase activity was induced or stimulated by either Fe deficiency or Cu depletion of the seedlings. Roots from both Fe-deficient and Cu-depleted plants were able to reduce exogenous Cu(II)-chelate as well as Fe(III)-chelate. When this reductase was induced by Fe deficiency, the accumulation of a number of mineral cations (i.e., Cu, Mn, Fe, Mg, and K) in leaves of pea seedlings was significantly increased. We suggest that, in addition to playing a critical role in Fe absorption, this plasma-membrane reductase system also plays a more general role in the regulation of cation absorption by Root Cells, possibly via the reduction of critical sulfhydryl groups in transport proteins involved in divalent-cation transport (divalent-cation channels?) across the Root-Cell plasmalemma.
Tom Denyer - One of the best experts on this subject based on the ideXlab platform.
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spatiotemporal developmental trajectories in the arabidopsis Root revealed using high throughput single Cell rna sequencing
Developmental Cell, 2019Co-Authors: Tom Denyer, Simon Klesen, Emanuele Scacchi, Kay Nieselt, Marja C P TimmermansAbstract:High-throughput single-Cell RNA sequencing (scRNA-seq) is becoming a cornerstone of developmental research, providing unprecedented power in understanding dynamic processes. Here, we present a high-resolution scRNA-seq expression atlas of the Arabidopsis Root composed of thousands of independently profiled Cells. This atlas provides detailed spatiotemporal information, identifying defining expression features for all major Cell types, including the scarce Cells of the quiescent center. These reveal key developmental regulators and downstream genes that translate Cell fate into distinctive Cell shapes and functions. Developmental trajectories derived from pseudotime analysis depict a finely resolved cascade of Cell progressions from the niche through differentiation that are supported by mirroring expression waves of highly interconnected transcription factors. This study demonstrates the power of applying scRNA-seq to plants and provides an unparalleled spatiotemporal perspective of Root Cell differentiation.
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spatiotemporal developmental trajectories in the arabidopsis Root revealed using high throughput single Cell rna sequencing
Social Science Research Network, 2018Co-Authors: Tom Denyer, Simon Klesen, Emanuele Scacchi, Kay Nieselt, Marja C P TimmermansAbstract:High-throughput single Cell RNA-sequencing (scRNA-seq) is becoming a cornerstone of developmental research, providing unprecedented power in understanding dynamic processes. Here, we present a high-resolution scRNA-seq expression atlas of the Arabidopsis Root, composed of thousands of independently profiled Cells. This atlas provides precise spatiotemporal information, identifying defining expression features for all major Cell types, including the scarce Cells of the quiescent centre. These reveal new developmental regulators and downstream genes that translate Cell fate into distinctive Cell shapes and functions. Developmental trajectories derived from pseudotime analysis depict a finely resolved cascade of Cell progressions from the niche through differentiation that are supported by mirroring expression waves of highly interconnected transcription factors. This study demonstrates the power of applying scRNA-seq to plants, and provides a unique spatiotemporal perspective of Root Cell differentiation.
Cuncang Jiang - One of the best experts on this subject based on the ideXlab platform.
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excess boron inhibited the trifoliate orange growth by inducing oxidative stress alterations in Cell wall structure and accumulation of free boron
Plant Physiology and Biochemistry, 2019Co-Authors: Muhammad Riaz, Lei Yan, Saddam Hussain, Omar Aziz, Zeinab Eldesouki, Cuncang JiangAbstract:The boron (B) is an essential nutrient and plays an important role in the stability of the primary Cell wall (CW). Due to the narrow window between B deficiency and toxicity, mismanagement practices lead to B toxicity that inhibit Root growth and overall crop productivity. However, the exact cause of Root growth inhibition remains unclear. The present study examined the potential causes and targets of B toxicity by studying interCellular mechanism. The trifoliate seedlings were cultured under excess B conditions. The results indicated that plant growth was inhibited by excess B, nevertheless, the effects were prominent on Roots and leaves. B toxicity exacerbated oxidative stress and Root Cell death. The analysis of CW functional groups, CW microstructure and B forms lead to the conclusion that alterations in CW, and accumulation of free-B and carbohydrates might cause inhibition of growth and visible symptoms of B toxicity.
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boron alleviates the aluminum toxicity in trifoliate orange by regulating antioxidant defense system and reducing Root Cell injury
Journal of Environmental Management, 2018Co-Authors: Muhammad Riaz, Lei Yan, Saddam Hussain, Omar Aziz, Yuhan Wang, Muhammad Imran, Cuncang JiangAbstract:Aluminium (Al) toxicity is the most important soil constraint for plant growth and development in acid soils (pH < 5.5) globally in agricultural regions. Boron (B) is an essential micronutrient for the growth and development of higher plants. The results of previous studies propose that B might ameliorate Al toxicity; however, none of the studies have been conducted on trifoliate orange to study this effect. Thus, a study was carried out in hydroponics comprising of two different Al concentrations, 0 and 400 μM. For every concentration, two B treatments (0 and 10 μM as H3BO3) were applied to investigate the B-induced alleviation of Al toxicity and exploring the underneath mechanisms. The results revealed that Al toxicity under B deficiency severely hampered the Root growth and physiology of plant, caused oxidative stress and membrane damage, leading to severe Root injury and damage. However, application of B under Al toxicity improved the Root elongation and photosynthesis, while reduced Al uptake and mobilization into plant parts. Moreover, B supply regulated the activities of antioxidant enzymes, proline, secondary metabolites (phenylalanine ammonia lyase and polyphenol oxidase) contents, and stabilized integrity of proteins. Our study results imply that B supply promoted Root growth as well as defense system by reducing reactive oxygen species (ROS) and Al concentrations in plant parts thus B induced alleviation of Al toxicity; a fact that might be significant for higher productivity of agricultural plants grown in acidic conditions.
Simon Klesen - One of the best experts on this subject based on the ideXlab platform.
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spatiotemporal developmental trajectories in the arabidopsis Root revealed using high throughput single Cell rna sequencing
Developmental Cell, 2019Co-Authors: Tom Denyer, Simon Klesen, Emanuele Scacchi, Kay Nieselt, Marja C P TimmermansAbstract:High-throughput single-Cell RNA sequencing (scRNA-seq) is becoming a cornerstone of developmental research, providing unprecedented power in understanding dynamic processes. Here, we present a high-resolution scRNA-seq expression atlas of the Arabidopsis Root composed of thousands of independently profiled Cells. This atlas provides detailed spatiotemporal information, identifying defining expression features for all major Cell types, including the scarce Cells of the quiescent center. These reveal key developmental regulators and downstream genes that translate Cell fate into distinctive Cell shapes and functions. Developmental trajectories derived from pseudotime analysis depict a finely resolved cascade of Cell progressions from the niche through differentiation that are supported by mirroring expression waves of highly interconnected transcription factors. This study demonstrates the power of applying scRNA-seq to plants and provides an unparalleled spatiotemporal perspective of Root Cell differentiation.
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spatiotemporal developmental trajectories in the arabidopsis Root revealed using high throughput single Cell rna sequencing
Social Science Research Network, 2018Co-Authors: Tom Denyer, Simon Klesen, Emanuele Scacchi, Kay Nieselt, Marja C P TimmermansAbstract:High-throughput single Cell RNA-sequencing (scRNA-seq) is becoming a cornerstone of developmental research, providing unprecedented power in understanding dynamic processes. Here, we present a high-resolution scRNA-seq expression atlas of the Arabidopsis Root, composed of thousands of independently profiled Cells. This atlas provides precise spatiotemporal information, identifying defining expression features for all major Cell types, including the scarce Cells of the quiescent centre. These reveal new developmental regulators and downstream genes that translate Cell fate into distinctive Cell shapes and functions. Developmental trajectories derived from pseudotime analysis depict a finely resolved cascade of Cell progressions from the niche through differentiation that are supported by mirroring expression waves of highly interconnected transcription factors. This study demonstrates the power of applying scRNA-seq to plants, and provides a unique spatiotemporal perspective of Root Cell differentiation.
