scholarly journals Apoplastic histochemical features of plant root walls that may facilitate ion uptake and retention

2021 ◽  
Vol 16 (1) ◽  
pp. 1347-1356
Author(s):  
Di Wu ◽  
Linbao Li ◽  
Chengdao Li ◽  
Bicheng Dun ◽  
Jun Zhang ◽  
...  
Keyword(s):  
Plant Root ◽  
Root Apex ◽  
Pteris Vittata ◽  
Root Cap ◽  
Pistia Stratiotes ◽  
Epifluorescence Microscopy ◽  
Alternanthera Philoxeroides ◽  
Indigenous Plants ◽  
Invasion Mechanisms

Abstract We used brightfield and epifluorescence microscopy, as well as permeability tests, to investigate the apoplastic histochemical features of plant roots associated with ion hyperaccumulation, invasion, and tolerance of oligotrophic conditions. In hyperaccumulator species with a hypodermis (exodermis absent), ions penetrated the root apex, including the root cap. By contrast, in non-hyperaccumulator species possessing an exodermis, ions did not penetrate the root cap. In vivo, the lignified hypodermis blocked the entry of ions into the cortex, while root exodermis absorbed ions and restricted them to the cortex. The roots of the hyperaccumulators Pteris vittata and Cardamine hupingshanensis, as well as the aquatic invasives Alternanthera philoxeroides, Eichhornia crassipes, and Pistia stratiotes, contained lignin and pectins. These compounds may trap and store ions before hypodermis maturation, facilitating ion hyperaccumulation and retention in the apoplastic spaces of the roots. These apoplastic histochemical features were consistent with certain species-specific characters, including ion hyperaccumulation, invasive behaviors in aquatic environments, or tolerance of oligotrophic conditions. We suggest that apoplastic histochemical features of the root may act as invasion mechanisms, allowing these invasive aquatic plants to outcompete indigenous plants for ions.

Cytological and histochemical characteristics of the axenic root surface of Alnus glutinosa

1986 ◽  
Vol 64 (10) ◽  
pp. 2216-2226 ◽  
Author(s):  
Yves Prin ◽  
Mireille Rougier
Keyword(s):  
Cell Wall ◽  
Root Hair ◽  
Root Hairs ◽  
Root Apex ◽  
Alnus Glutinosa ◽  
Root Surface ◽  
Infection Process ◽  
Root Cap ◽  
A Cell ◽  
Histochemical Tests

The aim of the present study was to investigate the Alnus root surface using seedlings grown axenically. This study has focused on root zones where infection by the symbiotic actinomycete Frankia takes place. The zones examined extend from the root cap to the emerging root hair zone. The root cap ensheaths the Alnus root apex and extends over the root surface as a layer of highly flattened cells closely appressed to the root epidermal cell wall. These cells contain phenolic compounds as demonstrated by various histochemical tests. They are externally bordered by a thin cell wall coated by a thin mucilage layer. The root cap is ruptured when underlying epidermal cells elongate, and cell remnants are still found in the emerging root hair zone. Young emerging root hairs are bordered externally by a cell wall covered by a thin mucilage layer which reacts positively to the tests used for the detection of polysaccharides, glycoproteins, and anionic sites. The characteristics of the Alnus root surface and the biological function of mucilage and phenols present at the root surface are discussed in relation to the infection process.

scholarly journals In silico identification and in vivo validation of a set of evolutionary conserved plant root-specific cis-regulatory elements

2013 ◽  
Vol 130 (1) ◽  
pp. 70-81 ◽  
Author(s):  
Aurélie Christ ◽  
Ira Maegele ◽  
Nati Ha ◽  
Hong Ha Nguyen ◽  
Martin D. Crespi ◽  
...  
Keyword(s):  
In Silico ◽  
Plant Root ◽  
Regulatory Elements ◽  
In Silico Identification ◽  
In Vivo Validation

scholarly journals A study on plant root apex morphology as a model for soft robots moving in soil

PLoS ONE ◽  
2018 ◽  
Vol 13 (6) ◽  
pp. e0197411 ◽  
Author(s):  
Anand Kumar Mishra ◽  
Francesca Tramacere ◽  
Roberto Guarino ◽  
Nicola Maria Pugno ◽  
Barbara Mazzolai
Keyword(s):  
Plant Root ◽  
Root Apex ◽  
Soft Robots

Inhibition of initial transport rate of basolateral organic anion carrier in renal PT by BK and phenylephrine

1999 ◽  
Vol 277 (2) ◽  
pp. F251-F256 ◽  
Author(s):  
Michael Gekle ◽  
Sigrid Mildenberger ◽  
Christoph Sauvant ◽  
Dallas Bednarczyk ◽  
Stephen H. Wright ◽  
...  
Keyword(s):  
Direct Action ◽  
Organic Anion ◽  
Specific Inhibitor ◽  
Peptide Hormone ◽  
Organic Anion Transporter ◽  
Epifluorescence Microscopy ◽  
Anion Transporter ◽  
Initial Uptake Rate ◽  
Continuous Presence

The effect of ligands for phospholipase C-coupled receptors and of protein kinase C (PKC) stimulation with phorbol ester [phorbol 12-myristate 13-acetate (PMA)] or 1,2-dioctanoyl- sn-glycerol on the activity of the basolateral organic anion transporter (OAT) in S2 segments of single, nonperfused rabbit proximal tubules (PT) was measured with the use of fluorescein and epifluorescence microscopy. The initial uptake rate (25 s, OAT activity) was measured in real time by using conditions similar to those found in vivo. Stimulation of PKC with PMA or 1,2-dioctanoyl- sn-glycerol led to an inhibition of OAT activity, which could be prevented by 10−7 mol/l of the PKC-specific inhibitor bisindolylmaleimide. The α1-receptor agonist phenylephrine as well as the peptide hormone bradykinin induced a reversible decrease of OAT activity, which was prevented by bisindolylmaleimide. The observed effect was not due to a decrease in the concentration of the counterion α-ketoglutarate or to impaired α-ketoglutarate recycling, because it was unchanged in the continuous presence of α-ketoglutarate or methyl succinate. We conclude that physiological stimuli can inhibit the activity of OAT in rabbit PT via PKC. The effect is not mediated by alterations in counterion availability but by a direct action on the OAT.

In vivo visualization of oxygen transport in microvascular network

1994 ◽  
Vol 267 (5) ◽  
pp. H2068-H2078 ◽  
Author(s):  
T. Itoh ◽  
K. Yaegashi ◽  
T. Kosaka ◽  
T. Kinoshita ◽  
T. Morimoto
Keyword(s):  
Oxygen Transport ◽  
Time Lag ◽  
Epifluorescence Microscopy ◽  
Oxygen Quenching ◽  
Microvascular Network ◽  
Membrane Technique ◽  
Po2 Measurement ◽  
Micropositioning System

Oxygen transport from the blood to the tissues is a diffusive process driven by the gradient of oxygen tension (PO2). We developed an oxygen-quenching fluorescent membrane that allowed visualization of the PO2 distribution near the microvessels as optical patterns on the membrane by epifluorescence microscopy. This membrane was highly gas permeable to allow PO2 measurement and was transparent enough to also permit observation of the microcirculation. In combination with a newly devised gastight chamber and a micropositioning system, this membrane technique made it possible to visualize the PO2 distribution in the rat mesenteric microvascular network under well-defined conditions. Our preliminary findings indicate that the oxygen distribution in the microvascular network is heterogeneous and suggest that there is considerable release of oxygen from the arterioles. The time lag of the system for tracking rapid PO2 changes in vitro was shown to be negligible, indicating that dynamic PO2 changes occurring in vivo can also be assessed. This technique should provide a novel tool for the study of oxygen transport and metabolism under normal and abnormal conditions.

scholarly journals Levantamento da infestação de plantas aquáticas em Porto Primavera antes do enchimento final do reservatório

2009 ◽  
Vol 27 (spe) ◽  
pp. 879-886 ◽  
Author(s):  
D Martins ◽  
R.A Pitelli ◽  
M.S Tomazella ◽  
R.H Tanaka ◽  
A.C.P Rodrigues
Keyword(s):  
Eichhornia Crassipes ◽  
Pistia Stratiotes ◽  
Alternanthera Philoxeroides ◽  
Typha Angustifolia ◽  
Pontederia Cordata ◽  
Eichhornia Azurea ◽  
Echinochloa Polystachya ◽  
Polygonum Lapathifolium ◽  
Paspalum Repens ◽  
Egeria Najas

O objetivo deste trabalho foi identificar as plantas aquáticas e os níveis de infestação de cada espécie em Porto Primavera antes do enchimento final do reservatório. Foram avaliados todos os focos de vegetação aquática no reservatório (72 pontos), sendo os pontos demarcados com um aparelho de GPS. As espécies foram identificadas e estimouse visualmente (tamanho da área) a distribuição proporcional das plantas no foco de infestação. Após a identificação, foram encontradas 18 espécies de plantas aquáticas vegetando no reservatório, das quais foram determinadas a frequência de espécie de planta aquática e a distribuição dentro do sistema de geração de energia. As espécies encontradas no reservatório foram: Eichhornia crassipes, Eichhornia azurea, Pistia stratiotes, Paspalum repens, Cyperus brevifolius, Paspalum conspersum, Echinochloa polystachya, Egeria densa, Egeria najas, Polygonum hidropiperoides, Polygonum lapathifolium, Alternanthera philoxeroides, Eleocharis sellowiana, Nymphaea ampla, Pontederia cordata, Salvinia auriculata, Salvinia rotundifolia e Typha angustifolia. As maiores frequências relativas foram observadas em: E. azurea (36,11%), E. crassipes (16,67%), P. stratiotes (13,89%), S. auriculata (13,89%), C. brevifolius (11,11%) e P. lapathifolium (6,94%).

ET-1 induced alterations of hepatic microcirculation: sinusoidal and extrasinusoidal sites of action

1994 ◽  
Vol 267 (1) ◽  
pp. G143-G149 ◽  
Author(s):  
M. Bauer ◽  
J. X. Zhang ◽  
I. Bauer ◽  
M. G. Clemens
Keyword(s):  
Recovery Period ◽  
Epifluorescence Microscopy ◽  
Microvascular Blood Flow ◽  
Red Cell ◽  
Hepatic Microcirculation ◽  
Cell Velocity ◽  
Red Cell Velocity ◽  
Sites Of Action ◽  
Systemic Application

Using epifluorescence microscopy, we investigated the dynamic changes in hepatic sinusoidal hemodynamics in vivo during continuous infusion of endothelin-1 (ET-1) in pentobarbital-anesthetized rats. ET-1 was infused for 20 min at rates of 2 or 10 pmol/min either systemically or into the portal vein, followed by a 90-min recovery period. In contrast to systemic application of ET-1 that did not cause a consistent hepatic microvascular effect, we observed two different patterns of microcirculatory alterations during portal application. Infusion of 2 pmol/min elicited a rapid, reversible decrease in sinusoidal diameter that was paralleled by a slight increase in red cell velocity, resulting in conservation of volumetric flow and sinusoid density. Infusion of 10 pmol/min resulted in a biphasic narrowing followed by transient increase in sinusoidal diameter and a profound and lasting decrease in red cell velocity, leading to an almost complete cessation of hepatic microvascular blood flow. These results indicate that ET-1 is a potent constrictor in the liver microcirculation in vivo and acts at both extrasinusoidal and sinusoidal sites, although the sinusoidal sites appear to be more sensitive to lower concentrations.

APPLICATION OF MICRO-PIXE AND ICP-MS TO ANALYSIS OF ELEMENTAL DISTRIBUTION IN ROOT APEX OF PLANTS

2001 ◽  
Vol 11 (03n04) ◽  
pp. 125-131 ◽  
Author(s):  
Y. WATANABE ◽  
S. HOMMA-TAKEDA ◽  
M. YUKAWA ◽  
Y. NISHIMURA ◽  
H. IMASEKI
Keyword(s):  
Inductively Coupled Plasma ◽  
Developmental Stages ◽  
Plant Root ◽  
Root Apex ◽  
Tissue Level ◽  
Essential Elements ◽  
Elemental Distribution ◽  
Inductively Coupled ◽  
Icp Ms ◽  
Almost All

Micro-PIXE and inductively coupled plasma mass spectrometry (ICP-MS) were applied to elemental distribution analyses in plant root apex which is composed of various types of tissues and cells in different developmental stages. ICP-MS was so sensitive that a large number of elements including Na, Mg, P, S, K, Ca, Mn, Fe, Cu, Zn, Se, Rb, Sr and Cs could be determined quantitatively. These fourteen elements included almost all the essential elements for plant growth. Only a rough estimation, however, could be obtained by ICP-MS for the elemental distribution at the tissue level, by analyzing sections from the root apex. On the other hand, micro-PIXE was effective for detailed mappings of elemental distributions. The images of elemental distributions were obtained for Na, Mg, P, S, K, Ca, Mn, Fe and Zn, corresponding to the microscopic images of the root structures. The localizations of P, K and Zn in some tissues were observed by the mappings. These results indicated that micro-PIXE and ICP-MS have different, but complementary abilities for the investigation of elemental distributions in plant tissues.

scholarly journals Molecular counting by photobleaching in protein complexes with many subunits: best practices and application to the cellulose synthesis complex

2014 ◽  
Vol 25 (22) ◽  
pp. 3630-3642 ◽  
Author(s):  
Yalei Chen ◽  
Nathan C. Deffenbaugh ◽  
Charles T. Anderson ◽  
William O. Hancock
Keyword(s):  
Best Practices ◽  
Protein Complexes ◽  
Epifluorescence Microscopy ◽  
Cellulose Synthesis ◽  
Complex Composition ◽  
Step Detection ◽  
Detection Algorithms ◽  
Large Numbers ◽  
Common Problems

The constituents of large, multisubunit protein complexes dictate their functions in cells, but determining their precise molecular makeup in vivo is challenging. One example of such a complex is the cellulose synthesis complex (CSC), which in plants synthesizes cellulose, the most abundant biopolymer on Earth. In growing plant cells, CSCs exist in the plasma membrane as six-lobed rosettes that contain at least three different cellulose synthase (CESA) isoforms, but the number and stoichiometry of CESAs in each CSC are unknown. To begin to address this question, we performed quantitative photobleaching of GFP-tagged AtCESA3-containing particles in living Arabidopsis thaliana cells using variable-angle epifluorescence microscopy and developed a set of information-based step detection procedures to estimate the number of GFP molecules in each particle. The step detection algorithms account for changes in signal variance due to changing numbers of fluorophores, and the subsequent analysis avoids common problems associated with fitting multiple Gaussian functions to binned histogram data. The analysis indicates that at least 10 GFP-AtCESA3 molecules can exist in each particle. These procedures can be applied to photobleaching data for any protein complex with large numbers of fluorescently tagged subunits, providing a new analytical tool with which to probe complex composition and stoichiometry.

scholarly journals Monocytes, neutrophils, and platelets cooperate to initiate and propagate venous thrombosis in mice in vivo

2012 ◽  
Vol 209 (4) ◽  
pp. 819-835 ◽  
Author(s):  
Marie-Luise von Brühl ◽  
Konstantin Stark ◽  
Alexander Steinhart ◽  
Sue Chandraratne ◽  
Ildiko Konrad ◽  
...  
Keyword(s):  
Time Course ◽  
Cardiovascular Death ◽  
Epifluorescence Microscopy ◽  
Factor Xii ◽  
Blood Monocytes ◽  
Extrinsic Pathway ◽  
Genetic Ablation ◽  
Vein Thrombosis ◽  
Sequence Of Events

Deep vein thrombosis (DVT) is a major cause of cardiovascular death. The sequence of events that promote DVT remains obscure, largely as a result of the lack of an appropriate rodent model. We describe a novel mouse model of DVT which reproduces a frequent trigger and resembles the time course, histological features, and clinical presentation of DVT in humans. We demonstrate by intravital two-photon and epifluorescence microscopy that blood monocytes and neutrophils crawling along and adhering to the venous endothelium provide the initiating stimulus for DVT development. Using conditional mutants and bone marrow chimeras, we show that intravascular activation of the extrinsic pathway of coagulation via tissue factor (TF) derived from myeloid leukocytes causes the extensive intraluminal fibrin formation characteristic of DVT. We demonstrate that thrombus-resident neutrophils are indispensable for subsequent DVT propagation by binding factor XII (FXII) and by supporting its activation through the release of neutrophil extracellular traps (NETs). Correspondingly, neutropenia, genetic ablation of FXII, or disintegration of NETs each confers protection against DVT amplification. Platelets associate with innate immune cells via glycoprotein Ibα and contribute to DVT progression by promoting leukocyte recruitment and stimulating neutrophil-dependent coagulation. Hence, we identified a cross talk between monocytes, neutrophils, and platelets responsible for the initiation and amplification of DVT and for inducing its unique clinical features.

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