Bibliografias temáticas / Ion channels Molecular aspects

Índice

Artigos de revistas
Teses / dissertações
Livros
Capítulos de livros
Trabalhos de conferências
Relatórios de organizações

Literatura científica selecionada sobre o tema "Ion channels Molecular aspects"

Autor: Grafiati

Publicado: 4 de junho de 2021

Última modificação: 28 de janeiro de 2023

Crie uma referência precisa em APA, MLA, Chicago, Harvard, e outros estilos

Selecione um tipo de fonte:

Consulte a lista de atuais artigos, livros, teses, anais de congressos e outras fontes científicas relevantes para o tema "Ion channels Molecular aspects".

Ao lado de cada fonte na lista de referências, há um botão "Adicionar à bibliografia". Clique e geraremos automaticamente a citação bibliográfica do trabalho escolhido no estilo de citação de que você precisa: APA, MLA, Harvard, Chicago, Vancouver, etc.

Você também pode baixar o texto completo da publicação científica em formato .pdf e ler o resumo do trabalho online se estiver presente nos metadados.

Artigos de revistas sobre o assunto "Ion channels Molecular aspects"

IMOTO, KEIJI. "Molecular Aspects of Ion Permeation through Channels". Annals of the New York Academy of Sciences 707, n.º 1 Molecular Bas (dezembro de 1993): 38–50. http://dx.doi.org/10.1111/j.1749-6632.1993.tb38040.x.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

Vacher, Helene, Durga P. Mohapatra e James S. Trimmer. "Localization and Targeting of Voltage-Dependent Ion Channels in Mammalian Central Neurons". Physiological Reviews 88, n.º 4 (outubro de 2008): 1407–47. http://dx.doi.org/10.1152/physrev.00002.2008.

Texto completo da fonte

Resumo:

The intrinsic electrical properties and the synaptic input-output relationships of neurons are governed by the action of voltage-dependent ion channels. The localization of specific populations of ion channels with distinct functional properties at discrete sites in neurons dramatically impacts excitability and synaptic transmission. Molecular cloning studies have revealed a large family of genes encoding voltage-dependent ion channel principal and auxiliary subunits, most of which are expressed in mammalian central neurons. Much recent effort has focused on determining which of these subunits coassemble into native neuronal channel complexes, and the cellular and subcellular distributions of these complexes, as a crucial step in understanding the contribution of these channels to specific aspects of neuronal function. Here we review progress made on recent studies aimed to determine the cellular and subcellular distribution of specific ion channel subunits in mammalian brain neurons using in situ hybridization and immunohistochemistry. We also discuss the repertoire of ion channel subunits in specific neuronal compartments and implications for neuronal physiology. Finally, we discuss the emerging mechanisms for determining the discrete subcellular distributions observed for many neuronal ion channels.

Estilos ABNT, Harvard, Vancouver, APA, etc.

Fahlke, Christoph. "Ion permeation and selectivity in ClC-type chloride channels". American Journal of Physiology-Renal Physiology 280, n.º 5 (1 de maio de 2001): F748—F757. http://dx.doi.org/10.1152/ajprenal.2001.280.5.f748.

Texto completo da fonte

Resumo:

Voltage-gated anion channels are present in almost every living cell and have many physiological functions. Recently, a novel gene family encoding voltage-gated chloride channels, the ClC family, was identified. The knowledge of primary amino acid sequences has allowed for the study of these anion channels in heterologous expression systems and made possible the combination of site-directed mutagenesis and high-resolution electrophysiological measurements as a means of gaining insights into the molecular basis of channel function. This review focuses on one particular aspect of chloride channel function, the selective transport of anions through biological membranes. I will describe recent experiments using a combination of cellular electrophysiology, molecular genetics, and recombinant DNA technology to study the molecular basis of ion permeation and selection in ClC-type chloride channels. These novel tools have provided new insights into basic mechanisms underlying the function of these biologically important channels.

Estilos ABNT, Harvard, Vancouver, APA, etc.

Tiffner, Adéla, Valentina Hopl e Isabella Derler. "CRAC and SK Channels: Their Molecular Mechanisms Associated with Cancer Cell Development". Cancers 15, n.º 1 (23 de dezembro de 2022): 101. http://dx.doi.org/10.3390/cancers15010101.

Texto completo da fonte

Resumo:

Cancer represents a major health burden worldwide. Several molecular targets have been discovered alongside treatments with positive clinical outcomes. However, the reoccurrence of cancer due to therapy resistance remains the primary cause of mortality. Endeavors in pinpointing new markers as molecular targets in cancer therapy are highly desired. The significance of the co-regulation of Ca2+-permeating and Ca2+-regulated ion channels in cancer cell development, proliferation, and migration make them promising molecular targets in cancer therapy. In particular, the co-regulation of the Orai1 and SK3 channels has been well-studied in breast and colon cancer cells, where it finally leads to an invasion-metastasis cascade. Nevertheless, many questions remain unanswered, such as which key molecular components determine and regulate their interplay. To provide a solid foundation for a better understanding of this ion channel co-regulation in cancer, we first shed light on the physiological role of Ca2+ and how this ion is linked to carcinogenesis. Then, we highlight the structure/function relationship of Orai1 and SK3, both individually and in concert, their role in the development of different types of cancer, and aspects that are not yet known in this context.

Estilos ABNT, Harvard, Vancouver, APA, etc.

Arcangeli, Annarosa. "Ion channels and transporters in cancer. 3. Ion channels in the tumor cell-microenvironment cross talk". American Journal of Physiology-Cell Physiology 301, n.º 4 (outubro de 2011): C762—C771. http://dx.doi.org/10.1152/ajpcell.00113.2011.

Texto completo da fonte

Resumo:

The traditional view of cancer as a collection of proliferating cells must be reconsidered, and cancer must be viewed as a “tissue” constituted by both transformed cells and a heterogeneous microenvironment, that tumor cells construct and remodel during multistep tumorigenesis. The “tumor microenvironment” (TM) is formed by mesenchymal, endothelial, and immune cells immersed in a network of extracellular matrix (ECM) proteins and soluble factors. The TM strongly contributes to tumor progression, through long distance, cell-to-cell or cell-to-matrix signals, which influence different aspects of tumor cell behavior. Understanding the relationships among the different components of the cancer tissue is crucial to design and develop new therapeutic strategies. Ion channels are emerging as relevant players in the cross talk between tumor cells and their TM. Ion channels are expressed on tumor cells, as well as in the different cellular components of the TM. In all these cells, ion channels are in a strategic position to sense and transmit extracellular signals into the intracellular machinery. Often, this transmission is mediated by integrin adhesion receptors, which can be functional partners of ion channels since they form molecular complexes with the channel protein in the context of the plasma membrane. The same relevant role is exerted by ion transporters, which also contribute to determine two facets of the cancer tissue: hypoxia and the acidic extracellular pH. On the whole, it is conceivable to prospect the targeting of ion channels for new therapeutic strategies aimed at better controlling the malignant progression of the cancer tissue.

Estilos ABNT, Harvard, Vancouver, APA, etc.

Hernández-Araiza, Ileana, Sara L. Morales-Lázaro, Jesús Aldair Canul-Sánchez, León D. Islas e Tamara Rosenbaum. "Role of lysophosphatidic acid in ion channel function and disease". Journal of Neurophysiology 120, n.º 3 (1 de setembro de 2018): 1198–211. http://dx.doi.org/10.1152/jn.00226.2018.

Texto completo da fonte

Resumo:

Lysophosphatidic acid (LPA) is a bioactive phospholipid that exhibits a wide array of functions that include regulation of protein synthesis and adequate development of organisms. LPA is present in the membranes of cells and in the serum of several mammals and has also been shown to participate importantly in pathophysiological conditions. For several decades it was known that LPA produces some of its effects in cells through its interaction with specific G protein-coupled receptors, which in turn are responsible for signaling pathways that regulate cellular function. Among the target proteins for LPA receptors are ion channels that modulate diverse aspects of the physiology of cells and organs where they are expressed. However, recent studies have begun to unveil direct effects of LPA on ion channels, highlighting this phospholipid as a direct agonist and adding to the knowledge of the field of lipid-protein interactions. Moreover, the roles of LPA in pathophysiological conditions associated with the function of some ion channels have also begun to be clarified, and molecular mechanisms have been identified. This review focuses on the effects of LPA on ion channel function under normal and pathological conditions and highlights our present knowledge of the mechanisms by which it regulates the function and expression of N- and T-type Ca++ channels; M-type K+ channel and inward rectifier K+ channel subunit 2.1; transient receptor potential (TRP) melastatin 2, TRP vanilloid 1, and TRP ankyrin 1 channels; and TWIK-related K+ channel 1 (TREK-1), TREK-2, TWIK-related spinal cord K+ channel (TRESK), and TWIK-related arachidonic acid-stimulated K+ channel (TRAAK).

Estilos ABNT, Harvard, Vancouver, APA, etc.

Kytikova, Oxana Yu, Tatyana P. Novgorodtseva, Yulia K. Denisenko, Denis E. Naumov, Tatyana A. Gvozdenko e Juliy M. Perelman. "Thermosensory Transient Receptor Potential Ion Channels and Asthma". Biomedicines 9, n.º 7 (14 de julho de 2021): 816. http://dx.doi.org/10.3390/biomedicines9070816.

Texto completo da fonte

Resumo:

Asthma is a widespread chronic disease of the bronchopulmonary system with a heterogeneous course due to the complex etiopathogenesis. Natural-climatic and anthropogenic factors play an important role in the development and progression of this pathology. The reception of physical and chemical environmental stimuli and the regulation of body temperature are mediated by thermosensory channels, members of a subfamily of transient receptor potential (TRP) ion channels. It has been found that genes encoding vanilloid, ankyrin, and melastatin TRP channels are involved in the development of some asthma phenotypes and in the formation of exacerbations of this pathology. The review summarizes modern views on the role of high and low temperatures in airway inflammation in asthma. The participation of thermosensory TRP channels (vanilloid, ankyrin, and melastatin TRP channels) in the reaction to high and low temperatures and air humidity as well as in the formation of bronchial hyperreactivity and respiratory symptoms accompanying asthma is described. The genetic aspects of the functioning of thermosensory TRP channels are discussed. It is shown that new methods of treatment of asthma exacerbations caused by the influence of temperature and humidity should be based on the regulation of channel activity.

Estilos ABNT, Harvard, Vancouver, APA, etc.

Weissmann, Carina, Adriana A. Albanese, Natalia E. Contreras, María N. Gobetto, Libia C. Salinas Castellanos e Osvaldo D. Uchitel. "Ion channels and pain in Fabry disease". Molecular Pain 17 (janeiro de 2021): 174480692110331. http://dx.doi.org/10.1177/17448069211033172.

Texto completo da fonte

Resumo:

Fabry disease (FD) is a progressive, X-linked inherited disorder of glycosphingolipid metabolism due to deficient or absent lysosomal α-galactosidase A (α-Gal A) activity which results in progressive accumulation of globotriaosylceramide (Gb3) and related metabolites. One prominent feature of Fabry disease is neuropathic pain. Accumulation of Gb3 has been documented in dorsal root ganglia (DRG) as well as other neurons, and has lately been associated with the mechanism of pain though the pathophysiology is still unclear. Small fiber (SF) neuropathy in FD differs from other entities in several aspects related to the perception of pain, alteration of fibers as well as drug therapies used in the practice with patients, with therapies far from satisfying. In order to develop better treatments, more information on the underlying mechanisms of pain is needed. Research in neuropathy has gained momentum from the development of preclinical models where different aspects of pain can be modelled and further analyzed. This review aims at describing the different in vitro and FD animal models that have been used so far, as well as some of the insights gained from their use. We focus especially in recent findings associated with ion channel alterations -that apart from the vascular alterations-, could provide targets for improved therapies in pain.

Estilos ABNT, Harvard, Vancouver, APA, etc.

Turner, Kathryn L., e Harald Sontheimer. "Cl − and K + channels and their role in primary brain tumour biology". Philosophical Transactions of the Royal Society B: Biological Sciences 369, n.º 1638 (19 de março de 2014): 20130095. http://dx.doi.org/10.1098/rstb.2013.0095.

Texto completo da fonte

Resumo:

Profound cell volume changes occur in primary brain tumours as they proliferate, invade surrounding tissue or undergo apoptosis. These volume changes are regulated by the flux of Cl − and K + ions and concomitant movement of water across the membrane, making ion channels pivotal to tumour biology. We discuss which specific Cl − and K + channels are involved in defined aspects of glioma biology and how these channels are regulated. Cl − is accumulated to unusually high concentrations in gliomas by the activity of the NKCC1 transporter and serves as an osmolyte and energetic driving force for volume changes. Cell volume condensation is required as cells enter M phase of the cell cycle and this pre-mitotic condensation is caused by channel-mediated ion efflux. Similarly, Cl − and K + channels dynamically regulate volume in invading glioma cells allowing them to adjust to small extracellular brain spaces. Finally, cell condensation is a hallmark of apoptosis and requires the concerted activation of Cl − and Ca 2+ -activated K + channels. Given the frequency of mutation and high importance of ion channels in tumour biology, the opportunity exists to target them for treatment.

Estilos ABNT, Harvard, Vancouver, APA, etc.

Flaxer, Eli. "Comprehensive Controller for Super Sonic Molecular Beam Gas Chromatograph Mass Spectrometer". Separations 9, n.º 12 (7 de dezembro de 2022): 417. http://dx.doi.org/10.3390/separations9120417.

Texto completo da fonte

Resumo:

This paper presents a new, comprehensive digital circuit used for the control of a novel gas chromatograph mass spectrometer (GC-MS) interface that is based on supersonic molecular beam (SMB). The circuit includes a Texas Instruments 150 MHz digital signal controller (DSC), high voltage amplifiers for 8 independent channels and 4 independent channels of high resolution pulse width modulation (PWM). The circuit, along with a sophisticated embedded program and a custom made personal computer (PC) application, control all aspects of the interface: smart filament emission-current stabilization, static and scanning mass-dependent ion-source voltages, transfer-line heater proportional integral differential (PID) controls with thermocouple feedbacks, on/off valves, relays and several peripheral device controls that enable the full operation of a turbo-molecular vacuum pump, and of gas flow and pressure controllers. All aspects of this comprehensive controller were successfully tested. The signal for the 450 Th ion (C32H66) for example increased by 123% which is a significant increase. It is obvious that correctly tuned dynamic voltages can guarantee the optimal signal for each mass.

Estilos ABNT, Harvard, Vancouver, APA, etc.

Mais fontes

Teses / dissertações sobre o assunto "Ion channels Molecular aspects"

Qiu, Min Ru Clinical School of Medicine St Vincent's Hospital UNSW. "Functional and molecular aspects of ion channels in macrophages". Awarded by:University of New South Wales. Clinical School of Medicine, St. Vincent's Hospital, 2003. http://handle.unsw.edu.au/1959.4/20442.

Texto completo da fonte

Resumo:

Monocytes/macrophages play very important roles in innate and adaptive immunity. Ion channels are small molecules embedded in the cell membrane and they play fundamental roles in cell function. Both topics have been extensively studied in isolation, however the role of ion channels in macrophage function is far less understood. In this thesis, the functional and molecular aspects of two ion channels expressed in macrophages, Kor, a potassium channel, and CLIC1, a chloride channel were studied. The biological function of Kor and CLIC1 in activated human macrophages was examined using ion channel blockers. In addition, the role of CLIC1 in the cell cycling of CHO-K1 cells was also investigated. The in vitro studies showed that Kor and CLIC1 are involved in cytokine production by PMA-activated human macrophages and that CLIC1 is also involved in the cell cycling of CHO-K1 cells. Despite providing interesting data, the results of the in vitro studies were difficult to interpret due to the uncertain specificities of the Cl- channel blockers. Therefore, to understand the biological role of CLIC1 in vivo, a gene targeting experiment was performed to create a CLIC1 knock-out (KO) mouse. This involved cloning the mouse CLIC1 gene, making a targeting vector, producing targeted ES cells, and generating a CLIC1 knock-in (KI) mouse which carries a flag tag at the N-terminal and three loxP sites in the targeted locus. Crossing the CLIC1 KI mouse with the TNAP-Cre mouse, a strain over expressing Cre recombinase under a TNAP promoter, a CLIC1 KO mouse was generated. The initial phenotype analysis showed no major development or growth abnormality in the CLIC1 KO mouse. Instead, hyperplasia of megakaryocytes and possible erythroid cells in the spleen and bone marrow was observed suggesting some degree of abnormality in the haematopoeitic system. Furthermore, a comparison of wild type mice with the CLIC1 KO mouse showed that CLIC1 protein expresses at high levels in monocytes, lymphocytes, platelets, and tissue macrophages of normal animals tissues, such as spleen, kidney (mesangial cell), and liver (kupffer cells). This further indicates that CLIC1 may play a significant role in regulating functions of platelets, lymphocytes, and specially tissue macrophages. More extensive studies can now be performed on the CLIC1 KO mouse to clarify the biological function of CLIC1. In summary, the generation of the CLIC1 KO mouse provides a valuable model to study the biological function of CLIC1 both in vivo and in vitro.

Estilos ABNT, Harvard, Vancouver, APA, etc.

Corry, Ben Alexander. "Simulation studies of biological ion channels". View thesis entry in Australian Digital Theses Program, 2002. http://thesis.anu.edu.au/public/adt-ANU20030423.162927/index.html.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

Amiri, Shiva. "Computational modelling and molecular dynamics simulations of ligand-gated ion channels". Thesis, University of Oxford, 2006. http://ora.ox.ac.uk/objects/uuid:119c7ccb-e7b2-4da1-a137-40c3289c3ad8.

Texto completo da fonte

Resumo:

Torpedo AChR structure was used to make models of other LGICs. Coarse-grain MD allowed the identification of residues in the TM domain interacting with the lipid-bilayer. Born energy profiles through LGIC pores reveal that the EC domain plays a key role in ion selectivity.

Estilos ABNT, Harvard, Vancouver, APA, etc.

Hedley, Paula Louise. "Molecular and functional characterisation of Long QT Syndrome causing genes". Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/86480.

Texto completo da fonte

Resumo:

Thesis (PhD)-- Stellenbosch University, 2014.
ENGLISH ABSTRACT: Ventricular arrhythmias are the most important cause of sudden cardiac death (SCD) among adults living in industrialised nations. Genetic factors have substantial effects in determining population-based risk for SCD and may also account for inter-individual variability in susceptibility. Great progress has been made in identifying genes underlying various Mendelian disorders associated with inherited arrhythmia susceptibility. The most well studied familial arrhythmia syndrome is the congenital long QT syndrome (LQTS) caused by mutations in genes encoding subunits of myocardial ion channels. Not all mutation carriers have equal risk for experiencing the clinical manifestations of disease (i.e. syncope, sudden death). This observation has raised the possibility that additional genetic factors may modify the risk of LQTS manifestations. This study establishes the genetic aetiology of LQTS in South Africa and Denmark through the identification and characterisation of LQTS-causative mutations in five previously identified genes, as well as examining possible novel genetic causes of LQTS in a cohort comprising Danish and British probands. We have functionally characterised several of the mutations identified in this study and examined other cardiac phenotypes that may be explained by variants causing repolarisation disorders.
AFRIKAANSE OPSOMMING: Ventrikulêre aritmie bly die enkele belangrikste oorsaak van skielike hart dood (SCD) onder volwassenes wat in geïndustrialiseerde lande woon. Genetiese faktore het aansienlike gevolge in die bepaling van bevolking-gebaseerde risiko vir SCD en kan ook verantwoordelik wees vir die inter-individuele variasie in vatbaarheid. Groot vordering is gemaak in die identifisering van gene onderliggende verskeie Mendeliese siektes wat verband hou met geërf aritmie vatbaarheid. Die mees goed bestudeerde familie aritmie sindroom is die aangebore lang QT-sindroom (LQTS) wat veroorsaak word deur mutasies in gene kode subeenhede van miokardiale ioonkanale. Nie alle mutasie draers het 'n gelyke risiko vir die ervaring van die kliniese manifestasies van die siekte (dws sinkopee, skielike dood). Hierdie waarneming het die moontlikheid genoem dat genetiese faktore anders as die primêre siekte-verwante mutasie kan die risiko van LQTS manifestasies verander. Hierdie studie stel die genetiese oorsake van LQTS in Suid-Afrika en Denemarke deur die identifisering en karakterisering van LQTS-veroorsakende mutasies in vyf voorheen geïdentifiseer gene, asook die behandeling van moontlike nuwe genetiese oorsake van LQTS in 'n groep wat bestaan uit van die Deense en die Britse probands. Ons het funksioneel gekenmerk verskeie van die mutasies wat in hierdie studie ondersoek en ander kardiovaskulêre fenotipes wat deur variante veroorsaak repolarisasie versteurings verduidelik word.
South African National Research Foundation
Harry and Doris Crossley Foundation
Danish Strategic Research Foundation.

Estilos ABNT, Harvard, Vancouver, APA, etc.

Breed, Jason. "Molecular modelling of ion channels". Thesis, University of Oxford, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.308690.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

Zhou, Xin. "Towards voltage-gated ion channels, molecular diodes". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0012/NQ32730.pdf.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

Bjelkmar, Pär. "Modeling of voltage-gated ion channels". Doctoral thesis, Stockholms universitet, Institutionen för biokemi och biofysik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-63437.

Texto completo da fonte

Resumo:

The recent determination of several crystal structures of voltage-gated ion channels has catalyzed computational efforts of studying these remarkable molecular machines that are able to conduct ions across biological membranes at extremely high rates without compromising the ion selectivity. Starting from the open crystal structures, we have studied the gating mechanism of these channels by molecular modeling techniques. Firstly, by applying a membrane potential, initial stages of the closing of the channel were captured, manifested in a secondary-structure change in the voltage-sensor. In a follow-up study, we found that the energetic cost of translocating this 310-helix conformation was significantly lower than in the original conformation. Thirdly, collaborators of ours identified new molecular constraints for different states along the gating pathway. We used those to build new protein models that were evaluated by simulations. All these results point to a gating mechanism where the S4 helix undergoes a secondary structure transformation during gating. These simulations also provide information about how the protein interacts with the surrounding membrane. In particular, we found that lipid molecules close to the protein diffuse together with it, forming a large dynamic lipid-protein cluster. This has important consequences for the understanding of protein-membrane interactions and for the theories of lateral diffusion of membrane proteins. Further, simulations of the simple ion channel antiamoebin were performed where different molecular models of the channel were evaluated by calculating ion conduction rates, which were compared to experimentally measured values. One of the models had a conductance consistent with the experimental data and was proposed to represent the biological active state of the channel. Finally, the underlying methods for simulating molecular systems were probed by implementing the CHARMM force field into the GROMACS simulation package. The implementation was verified and specific GROMACS-features were combined with CHARMM and evaluated on long timescales. The CHARMM interaction potential was found to sample relevant protein conformations indifferently of the model of solvent used.
At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 3: Manuscript.

Estilos ABNT, Harvard, Vancouver, APA, etc.

Adcock, Charlotte. "Molecular modelling and electrostatic properties of ion channels". Thesis, University of Oxford, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.297941.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

Bahnasi, Yahya Mohamed. "Molecular physiology and pharmacolgy of TRPC5 ion channels". Thesis, University of Leeds, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.496554.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

Elliott, David James Stuart. "Molecular mechanisms of voltage sensing by ion channels". Thesis, University of Leeds, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.406206.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

Mais fontes

Livros sobre o assunto "Ion channels Molecular aspects"

Society of General Physiologists. Symposium. Ion channels and genetic diseases. New York: Rockefeller University Press, 1995.

Encontre o texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

Boeynaems, J. M. Regulation of the vascular endothelium: Signals and transduction mechanisms. Austin: R.G.Landes, 1994.

Encontre o texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

NATO Advanced Research Workshop on Molecular Biology of Neuroreceptors and Ion Channels (1988 Thera Island, Greece). Molecular biology of neuroreceptors and ion channels. Berlin: Springer-Verlag, 1989.

Encontre o texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

Maelicke, Alfred, ed. Molecular Biology of Neuroreceptors and Ion Channels. Berlin, Heidelberg: Springer Berlin Heidelberg, 1989. http://dx.doi.org/10.1007/978-3-642-74155-5.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

Clark, J. Marshall, ed. Molecular Action of Insecticides on Ion Channels. Washington, DC: American Chemical Society, 1995. http://dx.doi.org/10.1021/bk-1995-0591.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

Becchetti, Andrea. Integrins and ion channels: Molecular complexes and signaling. New York: Springer Science+Business Media, 2010.

Encontre o texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

1963-, Becchetti Andrea, e Arcangeli Annarosa, eds. Integrins and ion channels: Molecular complexes and signaling. New York: Springer Science+Business Media, 2010.

Encontre o texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

Y, Kao C., Levinson S. R e New York Academy of Sciences., eds. Tetrodotoxin, saxitoxin, and the molecular biology of the sodium channel. New York, N.Y: New York Academy of Sciences, 1986.

Encontre o texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

Derek, Chadwick, Goode Jamie e Novartis Foundation, eds. Mammalian TRP channels as molecular targets. Chichester: John Wiley, 2004.

Encontre o texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

Morad, Martin, Setsuro Ebashi, Wolfgang Trautwein e Yoshihisa Kurachi, eds. Molecular Physiology and Pharmacology of Cardiac Ion Channels and Transporters. Dordrecht: Springer Netherlands, 1996. http://dx.doi.org/10.1007/978-94-011-3990-8.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

Mais fontes

Capítulos de livros sobre o assunto "Ion channels Molecular aspects"

Barchi, Robert L. "Molecular Aspects of Voltage-Dependent Ion Channels". In Advances in Experimental Medicine and Biology, 107–17. Boston, MA: Springer US, 1991. http://dx.doi.org/10.1007/978-1-4684-6015-5_9.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

Gillery, Marie-Jose, e Raoul Ranjeva. "Characterization of Calcium Channels in Carrot Cells". In Molecular and Cellular Aspects of Calcium in Plant Development, 421–22. Boston, MA: Springer US, 1986. http://dx.doi.org/10.1007/978-1-4613-2177-4_89.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

Nelson, Deborah J., e Harry A. Fozzard. "Ion Channels". In Principles of Molecular Regulation, 135–48. Totowa, NJ: Humana Press, 2000. http://dx.doi.org/10.1007/978-1-59259-032-2_8.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

Becchetti, Andrea, e Patrizia Aracri. "Ion Channels and Transporters". In Molecular Life Sciences, 1–22. New York, NY: Springer New York, 2014. http://dx.doi.org/10.1007/978-1-4614-6436-5_190-2.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

Becchetti, Andrea, e Patrizia Aracri. "Ion Channels and Transporters". In Molecular Life Sciences, 591–610. New York, NY: Springer New York, 2018. http://dx.doi.org/10.1007/978-1-4614-1531-2_190.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

Haerteis, Silke, e Stephan Kellenberger. "Acid-Sensing Ion Channels". In Encyclopedia of Molecular Pharmacology, 1–7. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-21573-6_10054-1.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

Haerteis, Silke, e Stephan Kellenberger. "Acid-Sensing Ion Channels". In Encyclopedia of Molecular Pharmacology, 18–24. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-57401-7_10054.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

Reuter, H. "Regulation of Ion Channels". In Molecular Mechanisms of Hormone Action, 126–31. Berlin, Heidelberg: Springer Berlin Heidelberg, 1989. http://dx.doi.org/10.1007/978-3-642-75022-9_15.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

Swandulla, Dieter, e Hanns Ulrich Zeilhofer. "Calcium Regulation of Ion Channels". In Integrative Aspects of Calcium Signalling, 79–97. Boston, MA: Springer US, 1998. http://dx.doi.org/10.1007/978-1-4899-1901-4_5.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

Dunn, Susan M. J., Manjunatha B. Bhat e A. Murat Öz. "The Molecular Structure and Gating of Calcium Channels". In Ion Channels and Ion Pumps, 1–18. New York, NY: Springer New York, 1994. http://dx.doi.org/10.1007/978-1-4612-2596-6_1.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

Trabalhos de conferências sobre o assunto "Ion channels Molecular aspects"

Cheng, C. H., Y. W. Chang e C. W. Hong. "Multi-Scale Analysis of Transport Phenomenon Inside the SOFC Using MD and CFD Techniques". In ASME 2004 2nd International Conference on Fuel Cell Science, Engineering and Technology. ASMEDC, 2004. http://dx.doi.org/10.1115/fuelcell2004-2491.

Texto completo da fonte

Resumo:

This paper analyzes the transport phenomenon of a solid oxide fuel cell (SOFC) from micro and macro aspects. The micro-scale model focuses on the ion hopping transportation inside the solid electrolyte and the macro-scale model aims at the flow phenomenon and thermal management inside the diffusion layers and the flow channel. In SOFCs, oxygen ions are conducted through the ceramic membrane of Yttria-Stablized Ziconia (YSZ), which is composed of ZrO2 and Y2O3. This paper uses molecular dynamics (MD) method to evaluate the ion conductivity of the solid electrolyte. Doping with different percentage of Y2O3, the ion hopping simulation shows that about 8 mole % gives the optimal performance. Also the higher the operation temperature, the better the ion conduction. Temperature field management is also a critical issue in the SOFC design. A set of three-dimensional computational fluid dynamics (CFD) model (including mass, momentum, energy and concentration equations) inside the porous diffusion layers and the flow channel of the SOFC were employed to estimate the cooling effect under different pattern of flow channel designs. All simulation results were validated with experiments reported from other literatures. The integration of the micro and macro-scale analyses proves to be versatile in the SOFC prototype design.

Estilos ABNT, Harvard, Vancouver, APA, etc.

Tieleman, D. Peter. "Molecular Motions in Ion Channels: a Possible Link to Noise in Single Channels". In UNSOLVED PROBLEMS OF NOISE AND FLUCTUATIONS: UPoN 2002: Third International Conference on Unsolved Problems of Noise and Fluctuations in Physics, Biology, and High Technology. AIP, 2003. http://dx.doi.org/10.1063/1.1584904.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

Diaz-Torres, A., D. J. Hinde, M. Dasgupta, G. J. Milburn, J. A. Tostevin, K. Ernst Rehm, Birger B. Back, Henning Esbensen e C. J. (Kim) Lister. "Coupled-Channels Approach for Dissipative Quantum Dynamics in Near-Barrier Collisions". In FUSION08: New Aspects of Heavy Ion Collisions Near the Coulomb Barrier. AIP, 2009. http://dx.doi.org/10.1063/1.3108859.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

Lukyanov, S. M., Yu E. Penionzhkevich, R. A. Astabatyan, N. A. Demekhina, Z. Dlouhy, M. P. Ivanov, R. Kalpakchieva et al. "The 2n-Evaporation Channels In the Fusion of [sup 4,6]He with [sup 206,208]Pb". In FUSION08: New Aspects of Heavy Ion Collisions Near the Coulomb Barrier. AIP, 2009. http://dx.doi.org/10.1063/1.3108814.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

Daiguji, Hirofumi. "Transport and Adsorption Phenomena in Mesoporous Silica". In ASME 2012 10th International Conference on Nanochannels, Microchannels, and Minichannels collocated with the ASME 2012 Heat Transfer Summer Conference and the ASME 2012 Fluids Engineering Division Summer Meeting. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/icnmm2012-73137.

Texto completo da fonte

Resumo:

The analysis and control of transport phenomena in fluidic nanopores and nanochannels is important in applications such as biochemical analysis, power generation and environmental protection. A unique aspect of nanofluidics is that the relevant length scale is comparable to the range of various surface and interfacial forces in liquids (such as electrostatic, van der Waals and steric interactions). Thus, to obtain an adequate description of transport phenomena in nanospace, it is necessary to understand the discreteness of molecules, especially when the size decreases to 2 nm. Micelle-templated mesoporous silicas (MPSs) possess highly ordered structures such as 2D hexagonal and 3D cubic structures and pores within the 2–50 nm range. In particular, 2D hexagonal films that generally have pore channels parallel to the surface plane have been widely synthesized by using various types of template molecules. If the pore channels of such materials are aligned in a certain direction, these materials can be employed for various purposes such as the fabrication of oriented nanowires, optoelectronic devices, recording media, selective separations, and nanofluidic systems. 3D cubic structures give large surface areas and become good candidates for highly efficient catalysts and sensors. Advances in the synthesis, measurement and analysis of nanotubes and nanochannels have allowed ion and liquid transport to be routinely examined and controlled in spaces with dimensions that range from 10 to 100 nm. The ability to now explore transport and adsorption phenomena in confined spaces of around 2 nm offers a range of possibilities. We have investigated several unique transport and adsorption phenomena in mesopores measuring a few nanometers in diameter, including nonlinear I–V curves of ionic current passing through MPS thin films filled with aqueous solutions, humidity-dependent adsorption rate of water into MPS, and the reduction of melting and freezing temperature of water in MPS.

Estilos ABNT, Harvard, Vancouver, APA, etc.

Spijker, Peter, Albert J. Markvoort, Huub M. M. ten Eikelder, Silvia V. Nedea e Peter A. J. Hilbers. "New Derivation of a Particle Wall Boundary Condition in Molecular Dynamics". In ASME 2007 5th International Conference on Nanochannels, Microchannels, and Minichannels. ASMEDC, 2007. http://dx.doi.org/10.1115/icnmm2007-30094.

Texto completo da fonte

Resumo:

In this paper a new particle wall boundary condition to replace explicit solid walls in molecular dynamics (MD) simulations is proposed. This new wall potential reduces the computational complexity considerably and allows the investigation of larger channels without compromising macroscopic quantities, such as density, temperature, pressure and heat flux. Since it is common practice in MD to truncate pair interaction potentials, an alternative and explicit derivation of the wall potential is possible, which is in contrast to previous work. Moreover, different types of crystal lattices can be included in the new potential. To demonstrate the applicablity of the method, MD simulations of a gas between two parallel plates at different temperatures and densities have been performed. The results of these simulations are compared to explicit wall simulations and previously proposed wall potentials. Although differences with other wall potentials are minor, some superior aspects of the new potential are addressed.

Estilos ABNT, Harvard, Vancouver, APA, etc.

Tavousi, Pouya, Meysam T. Chorsi, Caitlyn Mundrane, Vitaliy Gorbatyuk, Kazem Kazerounian e Horea Ilies. "Kinematic Design of Functional Nanoscale Mechanisms From Molecular Primitives". In ASME 2020 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/detc2020-22061.

Texto completo da fonte

Resumo:

Abstract Natural nanomechanisms such as capillaries, neurotransmitters, and ion channels play a vital role in the living systems. But the design principles developed by nature through evolution are not well understood and, hence, not applicable to engineered nanomachines. Thus, the design of nanoscale mechanisms with prescribed functions remains a challenge. Here, we present a systematic approach based on established kinematics techniques to designing, analyzing, and controlling manufacturable nanomachines with prescribed mobility and function built from a finite but extendable number of available “molecular primitives.” Our framework allows the systematic exploration of the design space of irreducibly simple nanomachines, built with prescribed motion specification by combining available nanocomponents into systems having constrained, and consequently controllable motions. We show that the proposed framework has allowed us to discover and verify a molecule in the form of a seven link, seven revolute (7R) close loop spatial linkage with mobility (degree of freedom) of one. Furthermore, our experiments exhibit the type and range of motion predicted by our simulations. Enhancing such a structure into functional nanomechanisms by exploiting and controlling their motions individually or as part of an ensemble could galvanize development of the multitude of engineering, scientific, medical, and consumer applications that can benefit from engineered nanomachines.

Estilos ABNT, Harvard, Vancouver, APA, etc.

Wang, Yu, e Zhenyu Liu. "Effect of Temperature on Velocity Profiles of Ions and Water Molecules in Charged Nanotubes". In ASME 2020 Heat Transfer Summer Conference collocated with the ASME 2020 Fluids Engineering Division Summer Meeting and the ASME 2020 18th International Conference on Nanochannels, Microchannels, and Minichannels. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/ht2020-9026.

Texto completo da fonte

Resumo:

Abstract High surface charge density makes it possible for charge inversion to occur in the electrical double layer, in which cases, flow reversal appears for electroosmotic driven flow that is one of the best-known methods of fluid transport based on the electro-kinetic phenomenon. Reverse electroosmotic flow of an aqueous solution of KCl was studied using MD method in this work. Nonequilibrium molecular dynamics simulations were carried out to investigate the effect of temperature on velocity profiles of ions and water molecules confined in charged carbon nanotubes (CNTs) with a diameter of 3.0 nm. The results demonstrate that the temperature dependence of velocity of ions and water molecules is obviously different for various distances to the tube wall. It is found that the temperature has a direct effect on the ion velocity profiles, that is, as the temperature increases, the velocity of either counter-ion or co-ion in the diffuse layer increases significantly though the velocity drops sharply in the vicinity of the tube wall surface. As for water molecules, the MD simulations show plenty of velocity profiles, in which the velocity is slightly positive near the tube wall, but is negative in most of the rest region. The temperature effect on reverse electroosmotic flow is clearly observed, which is reflected in two aspects: the viscosity of the fluid and the velocity profiles of ion and water molecule.

Estilos ABNT, Harvard, Vancouver, APA, etc.

Smith, Sonya T., e Richard Chadwick. "Nanofluidics of Mammalian Hearing". In ASME 2011 International Mechanical Engineering Congress and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/imece2011-64729.

Texto completo da fonte

Resumo:

The inner hair cell stereocilia bundle performs the role of transducer in mammalian hearing. Acoustic stimuli deflect the hair bundle to open ion channels, resulting in cation influx and the subsequent release of a neurotransmitter at the base of the cell. Hypotheses for this transduction include fluid shear-driven motion between the tectorial membrane and the reticular lamina to deflect the bundle. It is presumed that ‘molecular gates’ sense tension in tip-links that connect adjacent stepped rows of stereocilia to open the channels. However, almost nothing is known about the endolymphatic flow in the micron-sized gap surrounding the bundle and the nanoscale sized gaps between individual stereocilia rows and between individual bundles. Here we show with nanometer resolution, how each row of stereocilia, their associated tip links and gates and the corresponding flow patterns move in response to acoustical input.

Estilos ABNT, Harvard, Vancouver, APA, etc.

Kim, Daejoong, e Eric Darve. "Interactions of Wall Roughness and Electroosmotic Flows Inside Nanochannels". In ASME 3rd International Conference on Microchannels and Minichannels. ASMEDC, 2005. http://dx.doi.org/10.1115/icmm2005-75237.

Texto completo da fonte

Resumo:

We are reporting electroosmotic flows in nanochannels having different surface roughness. Molecular dynamics simulation technique has been applied to understand microscopic or molecular aspects of solid-liquid interactions. The surface roughness in this study was modeled as a succession of expanding and contracting steps along the flow direction, determined by the electric field direction. Water and sodium ion density profiles for the smooth wall show strong layering of water molecules near the solid wall. For rough walls, the density profiles are very similar for all cases except where the steps are located. We observed that this disturbance grows with the amplitude of the roughness and decreases with the period of the roughness. To further investigate strong layering of the water molecules, the net electric dipole moment was computed for the smooth and rough walls. It shows ordering of water molecules near the wall. The rough wall result show water molecules are ordered more in the expanded region. The velocity profiles and the flow rate were calculated for all cases. From these, electric double layers are found to overlap. The maximum velocities and the flow rate decreased for the lower period and the higher amplitude of surface roughness.

Estilos ABNT, Harvard, Vancouver, APA, etc.

Relatórios de organizações sobre o assunto "Ion channels Molecular aspects"

Marshall, Garland R. Molecular Mechanism of Voltage-Dependent Ion Channels. Fort Belvoir, VA: Defense Technical Information Center, novembro de 1990. http://dx.doi.org/10.21236/ada229777.

Texto completo da fonte

Estilos ABNT, Harvard, Vancouver, APA, etc.

Tel-Zur, Neomi, e Jeffrey J. Doyle. Role of Polyploidy in Vine Cacti Speciation and Crop Domestication. United States Department of Agriculture, janeiro de 2012. http://dx.doi.org/10.32747/2012.7697110.bard.

Texto completo da fonte

Resumo:

1. Abstract: Over the past 25 years, vine cacti of the genera Hylocereus and Selenicereus have been introduced into Israel and southern California as new exotic fruit crops. The importance of these crops lies in their high water use efficiency and horticultural potential as exotic fruit crops. Our collaboration focused on the cytological, molecular and evolutionary aspects of vine cacti polyploidization to confront the agricultural challenge of genetic improvement, ultimately to improve success of vine cacti as commercial fruit crop plants. More specifically, we worked on the: 1- Identification of the putative ancestor(s) of the tetraploid H. megalanthus; 2- Determination of the number of origins of H. megalanthus (single vs. multiple origins of polyploidy); 3- Cytogenetic analysis of BC1 and F1 hybrids; 4- Determination of important agricultural traits and the selection of superior hybrids for cultivation. The plant material used in this study comprised interspecific Hylocereus F1 and first backcross (BC1) hybrids, nine Hylocereus species (58 genotypes), nine Selenicereus species (14 genotypes), and four Epiphyllum genotypes. Two BC1 hexaploids (BC-023 and BC-031) were obtained, a high ploidy level that can be explained only by a fertilization event between one unreduced female gamete from the triploid hybrid and a balanced gamete from the pollen donor, the diploid H. monacanthus. These findings are scientific evidence that support the possibility that “hybridization followed by chromosome doubling” could also occur in nature. Cytomixis, the migration of chromatin between adjacent cells through connecting cytoplasmatic channels, was observed in vine cacti hybrids and may thus imply selective DNA elimination in response to the allopolyploidization process. Evidence from plastid and nrDNA internal transcribed spacers (ITS) sequences support the placement of H. megalanthus within a monophyletic Hylocereus group. Furthermore, both plastid and ITS datasets are most consistent with a conclusion that this tetraploid species is an autopolyploid, despite observations that the species appears to be morphologically intermediate between Hylocereus and Selenicereus. Although the possibility of very narrow allopolyploidly (i.e., derivation from parents that are barely diverged from each other such as closely related species in the same genus) cannot be ruled out entirely based on our data (in part due to the unavailability of Hylocereus species considered to be morphologically the closest relatives of H. megalanthus), the possibility of H. megalanthus representing an intergeneric cross (i.e., Hylocereus × Selenicereus) seems extremely unlikely. Interestingly, the process of homogenization of ITS sequences (concerted evolution) is either incomplete or lacking in both Hylocereus and Selenicereus, and the inclusion of several artificial hybrids in the molecular study revealed the potential for biparental plastid inheritance in Hylocereus. The most important agricultural implication of this research project was the information collected for F1 and BC1 hybrids. Specifically, this project concluded with the selection of four superior hybrids in terms of fruit quality and potential yields under extreme high temperatures. These selected hybrids are self-compatible, avoiding the need for hand cross pollination to set fruits, thus reducing manpower costs. We recently offered these hybrids to growers in Israel for prioritized rapid evaluation and characterization.

Estilos ABNT, Harvard, Vancouver, APA, etc.

Wackett, Lawrence, Raphi Mandelbaum e Michael Sadowsky. Bacterial Mineralization of Atrazine as a Model for Herbicide Biodegradation: Molecular and Applied Aspects. United States Department of Agriculture, janeiro de 1999. http://dx.doi.org/10.32747/1999.7695835.bard.

Texto completo da fonte

Resumo:

Atrazine is a broadly used herbicide in agriculture and it was used here as a model to study the biodegradation of herbicides. The bacterium Pseudomonas sp. ADP metabolizes atrazine to carbon dioxide and ammonia and chloride. The genes encoding atrazine catabolism to cyanuric acid were cloned and expressed in Escherichia coli. The genes were designated atzA, atzB and atzC. Each gene was sequenced. The enzyme activities were characterized. AtzA is atrazine chlorohydrolase which takes atrazine to hydroxyatrizine. AtzB is hydroxyatrazine N-ethylaminohydrolase which produces N-isopropylammelide and N-ethylamine. AtzC is N-isopropylammelide N-isopropylaminohydrolase which produces cyanuric acid and N-isopropylamine. Each product was isolated and characterized to confirm their identity by chromatography and mass spectrometry. Sequence analysis indicated that each of the hydrolytic enzymes AtzA, AtzB and AtzC share identity which the aminohydrolase protein superfamily. Atrazine chlorohydrolase was purified to homogeneity. It was shown to have a kcat of 11 s-1 and a KM of 150 uM. It was shown to require a metal ion, either Fe(II), Mn(II) or Co(II), for activity. The atzA, atzB and atzC genes were shown to reside on a broad-host range plasmid in Pseudomonas sp. ADP. Six other recently isolated atrazine-degrading bacteria obtained from Europe and the United States contained homologs to the atz genes identified in Pseudomonas sp. ADP. The identity of the sequences were very high, being greater than 98% in all pairwise comparisons. This indicates that many atrazine-degrading bacteria worldwide metabolize atrazine via a pathway that proceeds through hydroxyatrazine, a metabolite which is non-phytotoxic and non-toxic to mammals. Enzymes were immobilized and used for degradation of atrazine in aqueous phases. The in-depth understanding of the genomics and biochemistry of the atrazine mineralization pathway enabled us to study factors affecting the prevalence of atrazine degradation in various agricultural soils under conservative and new agricultural practices. Moreover, Pseudomonas sp. ADP and/or its enzymes were added to atrazine-contaminated soils, aquifers and industrial wastewater to increase the rate and extent of atrazine biodegradation above that of untreated environments. Our studies enhance the ability to control the fate of regularly introduced pesticides in agriculture, or to reduce the environmental impact of unintentional releases.

Estilos ABNT, Harvard, Vancouver, APA, etc.

Shani, Uri, Lynn Dudley, Alon Ben-Gal, Menachem Moshelion e Yajun Wu. Root Conductance, Root-soil Interface Water Potential, Water and Ion Channel Function, and Tissue Expression Profile as Affected by Environmental Conditions. United States Department of Agriculture, outubro de 2007. http://dx.doi.org/10.32747/2007.7592119.bard.

Texto completo da fonte

Resumo:

Constraints on water resources and the environment necessitate more efficient use of water. The key to efficient management is an understanding of the physical and physiological processes occurring in the soil-root hydraulic continuum.While both soil and plant leaf water potentials are well understood, modeled and measured, the root-soil interface where actual uptake processes occur has not been sufficiently studied. The water potential at the root-soil interface (yᵣₒₒₜ), determined by environmental conditions and by soil and plant hydraulic properties, serves as a boundary value in soil and plant uptake equations. In this work, we propose to 1) refine and implement a method for measuring yᵣₒₒₜ; 2) measure yᵣₒₒₜ, water uptake and root hydraulic conductivity for wild type tomato and Arabidopsis under varied q, K⁺, Na⁺ and Cl⁻ levels in the root zone; 3) verify the role of MIPs and ion channels response to q, K⁺ and Na⁺ levels in Arabidopsis and tomato; 4) study the relationships between yᵣₒₒₜ and root hydraulic conductivity for various crops representing important botanical and agricultural species, under conditions of varying soil types, water contents and salinity; and 5) integrate the above to water uptake term(s) to be implemented in models. We have made significant progress toward establishing the efficacy of the emittensiometer and on the molecular biology studies. We have added an additional method for measuring ψᵣₒₒₜ. High-frequency water application through the water source while the plant emerges and becomes established encourages roots to develop towards and into the water source itself. The yᵣₒₒₜ and yₛₒᵢₗ values reflected wetting and drying processes in the rhizosphere and in the bulk soil. Thus, yᵣₒₒₜ can be manipulated by changing irrigation level and frequency. An important and surprising finding resulting from the current research is the obtained yᵣₒₒₜ value. The yᵣₒₒₜ measured using the three different methods: emittensiometer, micro-tensiometer and MRI imaging in both sunflower, tomato and corn plants fell in the same range and were higher by one to three orders of magnitude from the values of -600 to -15,000 cm suggested in the literature. We have added additional information on the regulation of aquaporins and transporters at the transcript and protein levels, particularly under stress. Our preliminary results show that overexpression of one aquaporin gene in tomato dramatically increases its transpiration level (unpublished results). Based on this information, we started screening mutants for other aquaporin genes. During the feasibility testing year, we identified homozygous mutants for eight aquaporin genes, including six mutants for five of the PIP2 genes. Including the homozygous mutants directly available at the ABRC seed stock center, we now have mutants for 11 of the 19 aquaporin genes of interest. Currently, we are screening mutants for other aquaporin genes and ion transporter genes. Understanding plant water uptake under stress is essential for the further advancement of molecular plant stress tolerance work as well as for efficient use of water in agriculture. Virtually all of Israel’s agriculture and about 40% of US agriculture is made possible by irrigation. Both countries face increasing risk of water shortages as urban requirements grow. Both countries will have to find methods of protecting the soil resource while conserving water resources—goals that appear to be in direct conflict. The climate-plant-soil-water system is nonlinear with many feedback mechanisms. Conceptual plant uptake and growth models and mechanism-based computer-simulation models will be valuable tools in developing irrigation regimes and methods that maximize the efficiency of agricultural water. This proposal will contribute to the development of these models by providing critical information on water extraction by the plant that will result in improved predictions of both water requirements and crop yields. Plant water use and plant response to environmental conditions cannot possibly be understood by using the tools and language of a single scientific discipline. This proposal links the disciplines of soil physics and soil physical chemistry with plant physiology and molecular biology in order to correctly treat and understand the soil-plant interface in terms of integrated comprehension. Results from the project will contribute to a mechanistic understanding of the SPAC and will inspire continued multidisciplinary research.

Estilos ABNT, Harvard, Vancouver, APA, etc.

Oferecemos descontos em todos os planos premium para autores cujas obras estão incluídas em seleções literárias temáticas. Contate-nos para obter um código promocional único!