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Plant glutamate receptor-like (GLR) genes encode ion channels with demonstrated roles in electrical and calcium (Ca2+) signaling. The expansion of the GLR family along the lineage of land plants, culminating in the appearance of a multiclade system among flowering plants, has been a topic of interest since their discovery nearly 25 years ago. GLRs are involved in many physiological processes, from wound signaling to transcriptional regulation to sexual reproduction. Emerging evidence supports the notion that their fundamental functions are conserved among different groups of plants as well. In this review, we update the physiological and genetic evidence for GLRs, establishing their role in signaling and cell–cell communication. Special emphasis is given to the recent discussion of GLRs’ atomic structures. Along with functional assays, a structural view of GLRs’ molecular organization presents a window for novel hypotheses regarding the molecular mechanisms underpinning signaling associated with the ionic fluxes that GLRs regulate. Newly uncovered transcriptional regulations associated with GLRs—which propose the involvement of genes from all clades of Arabidopsis thaliana in ways not previously observed—are discussed in the context of the broader impacts of GLR activity. We posit that the functions of GLRs in plant biology are probably much broader than anticipated, but describing their widespread involvement will only be possible with ( a) a comprehensive understanding of the channel's properties at the molecular and structural levels, including protein–protein interactions, and ( b) the design of new genetic approaches to explore stress and pathogen responses where precise transcriptional control may result in more precise testable hypotheses to overcome their apparent functional redundancies.

Changes in cytosolic calcium concentration are among the earliest reactions to a multitude of stress cues. Whereas a plethora of calcium-permeable channels may generate distinct calcium signatures and contribute to response specificities, the mechanisms by which calcium signatures are decoded is poorly understood. Here we develop a genetically encoded, FRET-based reporter that visualizes the conformational change of calcium-dependent protein kinases (CDPKs/CPKs), preceding kinase activation, for calcium-dependent AtCPK21 and calcium-independent AtCPK23. In pollen tubes, naturally displaying a physiological calcium range, CPK21-FRET, but not CPK23-FRET, report activity oscillations with similar features to cytosolic calcium, suggesting an isoform-specific calcium dependency and reversibility of the conformational change. In guard cells CPK21-FRET identifies CPK21 as a decoder of signal-specific calcium signatures in response to ABA and flg22. Based on this data, CDPK-FRET stands as a novel approach for tackling real-time live-cell calcium decoding in a multitude of plant developmental and stress responses.

A COVID-19, doença causada pelo novo coronavírus, está afetando consideravelmente as práticas de saúde da maioria dos países. Ela se apresenta com sintomas respiratórios, culminando, algumas vezes, em morte ocasionada por Síndrome Respiratória Aguda Grave. Esse contexto exigiu uma mudança na organização dos sistemas de saúde, novos protocolos e alteração da atuação de profissionais, como do fisioterapeuta. A atuação desses profissionais no âmbito da reabilitação tem se mostrado muito útil ao prognóstico dos pacientes. Por isso, este busca revisar a literatura existente acerca da fisioterapia e reabilitação respiratória em pacientes portadores do novo coronavírus (SARS-CoV-2) e assim, levantar o atual estado dessa prática. Trata-se de um trabalho qualitativo, básico, exploratório e bibliográfico integrativo. A busca foi realizada utilizando os descritores: Physical Therapy, Intesive Physiotherapy, Coronavirus Infection e Respiration, nos repositórios Pubmed, Bireme e Springerlink e foram incluídos trabalhos em inglês e francês de 2020 e 2021. Os dados relatados sugerem que a fisioterapia fornece suporte ventilatório durante a fase aguda da doença e intervenções de reabilitação posteriores a fim de promover a funcionalidade. Apesar de não existir evidências que ela altere o curso do COVID-19 na fase aguda da doença em pacientes com insuficiência respiratória hipoxêmica e tosse seca, pacientes com tosse produtiva podem se beneficiar de manobras de higiene brônquica que estimulem a tosse. Fornecimento de oxigênio, ventilação mecânica não invasiva, desmame da ventilação assistida e desobstrução das vias aéreas são aplicados, manobras de mobilização precoce e variação da postura são efetuadas cotidianamente. Contudo, para pacientes com ventilação mecânica invasiva, há poucas indicações do trabalho fisioterápico, que tem principalmente um papel de monitoramento e posicionamento do paciente para otimizar a razão ventilação/perfusão. A posição prona é recomendada para pacientes em situação grave. Além disso, são garantidas todas as ações que promovam a autonomia respiratória do paciente, quando as condições clínicas permitem. Considera-se que há pouca base de dados relatados na literatura para uma discussão concisa acerca do tema proposto. Contudo, pode-se inferir que existem evidências de que a fisioterapia para o paciente acometido pela COVID-19 auxilia no prognóstico, na medida em que proporciona melhor oxigenação e trocas gasosas, além de oferecer técnicas de desobstrução das vias aéreas para pacientes ventilados e auxiliar no posicionamento de pacientes com insuficiência respiratória grave. Evidentemente, o acompanhamento, no decorrer da enfermidade e na recuperação, é importante para o acometido que apresenta melhor evolução clínica.

Physiological oscillations (or rhythms) pervade all spatiotemporal scales of biological organization, either because they perform critical functions or simply because they can arise spontaneously and may be difficult to prevent. Regardless of the case, they reflect regulatory relationships between control points of a given system and offer insights as read-outs of the concerted regulation of a myriad of biological processes. Here we review recent advances in understanding ultradian oscillations (period < 24h) in plant cells, with a special focus on single-cell oscillations. Ion channels are at the center stage due to their involvement in electrical/excitabile phenomena associated with oscillations and cell-cell communication. We highlight the importance of quantitative approaches to measure oscillations in appropriate physiological conditions, which are essential strategies to deal with the complexity of biological rhythms. Future development of optogenetics techniques in plants will further boost research on the role of membrane potential in oscillations and waves across multiple cell types.

Ion-specific probes and fluorescent indicators have been key in establishing the role of ion signaling, namely calcium, protons, and anions, in plant development, providing a robust approach for monitoring spatiotemporal changes in intracellular ion dynamics. The integration of protons/pH in signaling mechanisms is especially important as reports of their biological functions continue to expand; however, attaining quantitative estimates with high spatiotemporal resolution in single cells poses a major research challenge. Here, we detail the use of the genetically encoded pH-sensitive pHluorin reporter expressed in Arabidopsis thaliana pollen tubes to assess cytosolic measurements with calibration to provide actual pH values. This technique enabled us to identify critical phenotypes and establish the importance of tip-focused pH gradient for pollen tube growth, although it can be adapted to other experimental systems.

Wounding is a trigger for both regeneration and defense in plants, but it is not clear whether the two responses are linked by common activation or regulated as trade-offs. Although plant glutamate-receptor-like proteins (GLRs) are known to mediate defense responses, here, we implicate GLRs in regeneration through dynamic changes in chromatin and transcription in reprogramming cells near wound sites. We show that genetic and pharmacological inhibition of GLR activity increases regeneration efficiency in multiple organ repair systems in Arabidopsis and maize. We show that the GLRs work through salicylic acid (SA) signaling in their effects on regeneration, and mutants in the SA receptor NPR1 are hyper-regenerative and partially resistant to GLR perturbation. These findings reveal a conserved mechanism that regulates a trade-off between defense and regeneration, and they also offer a strategy to improve regeneration in agriculture and conservation.

Wounding is a trigger for both regeneration and defense in plants, but it is not clear if the two responses are linked by common activation or regulated as tradeoffs. While plant glutamate-like receptors (GLRs) are known to mediate defense, here we implicate GLRs in regeneration through dynamic changes in chromatin and transcription in reprogramming cells near wound sites. We show that genetic and pharmacological inhibition of GLR activity increases regeneration efficiency in multiple organ repair systems and plant species. Perturbation of GLR-mediated function speeds cell division and re-specification of the stem cell niche while dampening defense responses. We show that the GLRs work through salicylic acid (SA) signaling in regeneration, with mutants in the SA receptor NPR1 partially resistant to GLR perturbation and hyper regenerative. These findings reveal a conserved mechanism that regulates a tradeoff between defense and regeneration and offer new strategies to improve regeneration in agriculture and conservation.

The ion-selective vibrating probe has been used to detect and quantify the magnitude and direction of transmembrane fluxes of several ions in a wide range of biological systems. Inherently non-invasive, vibrating probes have been essential to access relevant electrophysiological parameters related to apical growth and morphogenesis in pollen tubes, a highly specialized cell where spatiotemporal tuning of ion dynamics is fundamental. Of relevance, crucial processes to the cell physiology of pollen tubes associated with protons and anions have been elucidated using vibrating probes, allowing the identification of diverse molecular players underlying and regulating their extracellular fluxes. The use of Arabidopsis thaliana as a genetic model system posed new challenges given their relatively small dimensions and difficult manipulation in vitro. Here, we describe protocol optimizations that made the use of the ion-selective vibrating probe in Arabidopsis pollen tubes feasible, ensuring consistent and reproducible data. Quantitative methods like this enabled characterizing phenotypes of ion transporter mutants, which are not directly detectable by evident morphological and reproductive defects, providing valuable insights into molecular and cellular mechanisms. The protocol for quantifying extracellular proton and anionic fluxes detailed here can be adjusted to other systems and species, while the sample preparation can be applied to correlated techniques, facilitating the research of pollen tube growth and development.

Whereas the role of calcium ions (Ca\(^{2+}\)) in plant signaling is well studied, the physiological significance of pH‐changes remains largely undefined. Here we developed CapHensor, an optimized dual‐reporter for simultaneous Ca\(^{2+}\) and pH ratio‐imaging and studied signaling events in pollen tubes (PTs), guard cells (GCs), and mesophyll cells (MCs). Monitoring spatio‐temporal relationships between membrane voltage, Ca\(^{2+}\)‐ and pH‐dynamics revealed interconnections previously not described. In tobacco PTs, we demonstrated Ca\(^{2+}\)‐dynamics lag behind pH‐dynamics during oscillatory growth, and pH correlates more with growth than Ca\(^{2+}\). In GCs, we demonstrated abscisic acid (ABA) to initiate stomatal closure via rapid cytosolic alkalization followed by Ca2+ elevation. Preventing the alkalization blocked GC ABA‐responses and even opened stomata in the presence of ABA, disclosing an important pH‐dependent GC signaling node. In MCs, a flg22‐induced membrane depolarization preceded Ca2+‐increases and cytosolic acidification by c. 2 min, suggesting a Ca\(^{2+}\)/pH‐independent early pathogen signaling step. Imaging Ca2+ and pH resolved similar cytosol and nuclear signals and demonstrated flg22, but not ABA and hydrogen peroxide to initiate rapid membrane voltage‐, Ca\(^{2+}\)‐ and pH‐responses. We propose close interrelation in Ca\(^{2+}\)‐ and pH‐signaling that is cell type‐ and stimulus‐specific and the pH having crucial roles in regulating PT growth and stomata movement.

The phytohormone ethylene has numerous effects on plant growth and development. Its immediate precursor, 1-aminocyclopropane-1-carboxylic acid (ACC), is a non-proteinogenic amino acid produced by ACC SYNTHASE (ACS). ACC is often used to induce ethylene responses. Here, we demonstrate that ACC exhibits ethylene-independent signaling in Arabidopsis thaliana reproduction. By analyzing an acs octuple mutant with reduced seed set, we find that ACC signaling in ovular sporophytic tissue is involved in pollen tube attraction, and promotes secretion of the pollen tube chemoattractant LURE1.2. ACC activates Ca2+-containing ion currents via GLUTAMATE RECEPTOR-LIKE (GLR) channels in root protoplasts. In COS-7 cells expressing moss PpGLR1, ACC induces the highest cytosolic Ca2+ elevation compared to all twenty proteinogenic amino acids. In ovules, ACC stimulates transient Ca2+ elevation, and Ca2+ influx in octuple mutant ovules rescues LURE1.2 secretion. These findings uncover a novel ACC function and provide insights for unraveling new physiological implications of ACC in plants., Ethylene is synthesized from the non-proteinogenic amino acid ACC. Here, Mou et al. show that ACC itself acts independently of ethylene to trigger secretion of a pollen tube attractant in the sporophytic tissue of Arabidopsis ovules and can activate Ca2+-currents via GLUTAMATE RECEPTOR-LIKE channels.

Conspicuous intracellular gradients manifest and/or drive intracellular polarity in pollen tubes. However, quantifying these gradients raises multiple technical challenges. Here we present a sensible computational protocol to analyze gradients in growing pollen tubes and to filter nonrepresentative time points. As an example, we use imaging data from pollen tubes expressing a genetically encoded ratiometric Ca

Pollen tubes are highly polarized tip-growing cells that depend on cytosolic pH gradients for signaling and growth. Autoinhibited plasma membrane proton (H+) ATPases (AHAs) have been proposed to energize pollen tube growth and underlie cell polarity, however, mechanistic evidence for this is lacking. Here we report that the combined loss of AHA6, AHA8, and AHA9 in Arabidopsis thaliana delays pollen germination and causes pollen tube growth defects, leading to drastically reduced fertility. Pollen tubes of aha mutants had reduced extracellular proton (H+) and anion fluxes, reduced cytosolic pH, reduced tip-to-shank proton gradients, and defects in actin organization. Furthermore, mutant pollen tubes had less negative membrane potentials, substantiating a mechanistic role for AHAs in pollen tube growth through plasma membrane hyperpolarization. Our findings define AHAs as energy transducers that sustain the ionic circuit defining the spatial and temporal profiles of cytosolic pH, thereby controlling downstream pH-dependent mechanisms essential for pollen tube elongation, and thus plant fertility.

A pesquisa objetiva demonstrar os benefícios da gestão da qualidade como ferramenta para otimização da prestação jurisdicional, se aplicada pelo Poder Judiciário do Estado do Tocantins (PJTO), tendo como referência a teoria do gerencialismo como modelo para a gestão pública. Na perspectiva teórica e, sob o enfoque jurídico, a pesquisa fundamentase no princípio constitucional da eficiência na administração pública relacionados aos princípios da gestão da qualidade. Na perspectiva empírica, através da análise de sistemas de gestão da qualidade já implantados, de modo a identificar como a aplicação dos princípios da qualidade na administração judiciária no PJTO poderia propiciar a melhoraria da eficácia da prestação jurisdicional. Assim, são abordados os temas da crise na administração pública e na administração judiciária. Através de uma revisão bibliográfica em livros e artigos levantou-se as contribuições de autores sobre o tema em análise. Uma correlação entre os princípios da qualidade e a realidade encontrada na administração de unidades judiciárias, através das fontes analisadas para o estudo, foi realizada com o fim de demonstrar a validade da aplicação dos princípios para nortear as mudanças necessárias para a melhoria da prestação jurisdicional e a aumentar a satisfação da sociedade. A pesquisa empírica foi realizada mediante a aplicação de um questionário, respondido por magistrados e servidores que atuam em unidades dos órgãos componentes da amostra com sistemas de gestão da qualidade implantados e certificados conforme o padrão ISO 9001, com o objetivo de compreender a percepção dos colaboradores da organização quanto ao sistema de gestão da qualidade (SGQ) e a certificação destas unidades. Com base nos resultados da pesquisa bibliográfica e da empírica foi possível confirmar a aplicabilidade de um SGQ, conforme o modelo da norma ABNT NBR ISO 9001:2015, como uma alternativa eficaz para que o Poder Judiciário apresente a resposta mais adequada para a necessidade de melhoria na eficiência da gestão, materializados no produto final proposto que são os modelos de um manual da qualidade e de procedimentos operacionais aplicáveis a qualquer unidade judiciária do PJTO. This thesis aims to demonstrate the benefits of quality management as a tool for optimizing jurisdictional delivery, when applied by the Judiciary of the State of Tocantins (PJTO), having as reference the theory of managerialism as a model for public management. From a theoretical a legal perspective, this thesis is based on the constitutional principle of efficiency in public administration related to the principles of quality management. From an empirical perspective, through the analysis of quality management systems already in place, in order to identify how the application of the principles of quality to the judiciary in the PJTO could improve the effectiveness of the judicial service. Thus, the themes of the crisis in public administration and judicial administration are addressed. Through a bibliographic review in books and articles, the contributions of authors on the subject under analysis were raised. A correlation between the principles of quality and the reality found in the administration of judicial units, through the sources analyzed for the study, was made in order to demonstrate the validity of the application of the principles to guide the necessary changes for the improvement of the judicial provision and the increase of society's satisfaction. The empirical research was conducted through the application of a questionnaire, answered by justices and public servers who work in units of the sample component bodies with quality management systems in place and certified according to the ISO 9001 standard, in order to understand the perception of employees, the quality management system and the certification of these units. Based on the results of the literature review and empirical research, it was possible to confirm the applicability of a quality management system, according to the model of the norm ABNT NBR ISO 9001: 2015, as an effective alternative for the Judiciary Power to present the most adequate answer for this need for improvement in management efficiency, embodied in the proposed final product, which are the models of a quality manual and operational procedures applicable to any judiciary unit of the PJTO.

Multiple, diverse, and complex Calcium currents characterize the developing pollen tube in the small mustard plant Arabidopsis and correlate with growth at the tip of the pollen tube. This system constitutes a practical model for screening for Ca 2+ -signaling mechanisms in plants. Wudick et al. analyzed multiple variants of glutamate receptor–like (GLR) channels and discovered that some work alone and others work in pairs or trios. Subcellular localization of GLRs is a complex response to CORNICHON sorting proteins, which leave some GLRs at the plasma membrane and ferry others to internal calcium reservoirs. The calcium current at the tip of the growing pollen tube apparently integrates multiple intracellular currents. Science , this issue p. 533

Pollen tubes (PTs) are characterized by having tip-focused cytosolic calcium ion (Ca2+ ) concentration ([Ca2+ ]cyt ) gradients, which are believed to control PT growth. However, the mechanisms by which the apical [Ca2+ ]cyt orchestrates PT growth are not well understood. Here, we aimed to identify these mechanisms by combining reverse genetics, cell biology, electrophysiology, and live-cell Ca2+ and anion imaging. We triggered Ca2+ -channel activation by applying hyperpolarizing voltage pulses and observed that the evoked [Ca2+ ]cyt increases were paralleled by high anion channel activity and a decrease in the cytosolic anion concentration at the PT tip. We confirmed a functional correlation between these patterns by showing that inhibition of Ca2+ -permeable channels eliminated the [Ca2+ ]cyt increase, resulting in the abrogation of anion channel activity via Ca2+ -dependent protein kinases (CPKs). Functional characterization of CPK and anion-channel mutants revealed a CPK2/20/6-dependent activation of SLAH3 and ALMT12/13/14 anion channels. The impaired growth phenotypes of anion channel and CPK mutants support the physiological significance of a kinase- and Ca2+ -dependent pathway to control PT growth via anion channel activation. Other than unveiling this functional link, our membrane hyperpolarization method allows for unprecedented manipulation of the [Ca2+ ]cyt gradient or oscillations in the PT tips and opens an array of opportunities for channel screenings.

Glutamate receptor-like channels (GLRs) play vital roles in various physiological processes in plants, such as wound response, stomatal aperture control, seed germination, root development, innate immune response, pollen tube growth, and morphogenesis. Despite the importance of GLRs, knowledge about their molecular organization is limited. Here we employ X-ray crystallography and single-particle cryo-EM to solve structures of the Arabidopsis thaliana GLR3.4. Our structures reveal the tetrameric assembly of GLR3.4 subunits into a three-layer domain architecture, reminiscent of animal ionotropic glutamate receptors (iGluRs). However, the non-swapped arrangement between layers of GLR3.4 domains, binding of glutathione through S-glutathionylation of cysteine C205 inside the amino-terminal domain clamshell, unique symmetry, inter-domain interfaces, and ligand specificity distinguish GLR3.4 from representatives of the iGluR family and suggest distinct features of the GLR gating mechanism. Our work elaborates on the principles of GLR architecture and symmetry and provides a molecular template for deciphering GLR-dependent signaling mechanisms in plants.

A data analysis pipeline that integrates diverse data sources, detects tip growth in kymographs, and analyses oscillations and synchronization reveales oscillatory signatures underlying distinct growth regimes in Arabidopsis pollen tubes., Oscillations in pollen tubes have been reported for many cellular processes, including growth, extracellular ion fluxes, and cytosolic ion concentrations. However, there is a shortage of quantitative methods to measure and characterize the different dynamic regimes observed. Herein, a suite of open-source computational methods and original algorithms were integrated into an automated analysis pipeline that we employed to characterize specific oscillatory signatures in pollen tubes of Arabidopsis thaliana (Col-0). Importantly, it enabled us to detect and quantify a Ca2+ spiking behaviour upon growth arrest and synchronized oscillations involving growth, extracellular H+ fluxes, and cytosolic Ca2+, providing the basis for novel hypotheses. Our computational approach includes a new tip detection method with subpixel resolution using linear regression, showing improved ability to detect oscillations when compared to currently available methods. We named this data analysis pipeline ‘Computational Heuristics for Understanding Kymographs and aNalysis of Oscillations Relying on Regression and Improved Statistics’, or CHUKNORRIS. It can integrate diverse data types (imaging, electrophysiology), extract quantitative and time-explicit estimates of oscillatory characteristics from isolated time series (period and amplitude) or pairs (phase relationships and delays), and evaluate their synchronization state. Here, its performance is tested with ratiometric and single channel kymographs, ion flux data, and growth rate analysis.

Conspicuous intracellular gradients manifest and/or drive intracellular polarity in pollen tubes. However, quantifying these gradients raises multiple technical challenges. Here we present a sensible computational protocol to analyze gradients in growing pollen tubes and to filter nonrepresentative time points. As an example, we use imaging data from pollen tubes expressing a genetically encoded ratiometric Ca2+ probe, Yellow CaMeleon 3.6, from which a kymograph is extracted. The tip of the pollen tube is detected with CHUKNORRIS, our previously published methodology, allowing the reconstruction of the intracellular gradient through time. Statistically confounding time points, such as growth arrest where gradients are highly oscillatory, are filtered out and a mean spatial profile is estimated with a local polynomial regression method. Finally, we estimate the gradient slope by the linear portion of the decay in mean fluorescence, offering a quantitative method to detect phenotypes of gradient steepness, location, intensity, and variability. The data manipulation protocol proposed can be achieved in a simple and efficient manner using the statistical programming language R, opening paths to perform high-throughput spatiotemporal phenotyping of intracellular gradients in apically growing cells.

Pollen tubes are highly polarized tip-growing cells that depend on cytosolic pH gradients for signaling and growth. Autoinhibited plasma membrane proton (H+) ATPases (AHAs) have been proposed to energize pollen tube growth and underlie cell polarity, however, mechanistic evidence for this is lacking. Here we report that the combined loss of AHA6, AHA8, and AHA9 in Arabidopsis thaliana delays pollen germination and causes pollen tube growth defects, leading to drastically reduced fertility. Pollen tubes of aha mutants had reduced extracellular proton (H+) and anion fluxes, reduced cytosolic pH, reduced tip-to-shank proton gradients, and defects in actin organization. Furthermore, mutant pollen tubes had less negative membrane potentials, substantiating a mechanistic role for AHAs in pollen tube growth through plasma membrane hyperpolarization. Our findings define AHAs as energy transducers that sustain the ionic circuit defining the spatial and temporal profiles of cytosolic pH, thereby controlling downstream pH-dependent mechanisms essential for pollen tube elongation, and thus plant fertility., Cytosolic ion gradients in growing pollen tubes are thought to be required for polar growth. Here the authors show that the Arabidopsis plasma membrane H+ ATPases, AHA6, AHA8, and AHA9, maintain tip-to-shank proton gradients, oscillations in cytosolic pH and actin organization to enable pollen tube elongation.

SummaryNitric oxide (NO) is a key signaling molecule that regulates diverse biological processes in both animals and plants. In animals, NO regulates vascular wall tone, neurotransmission and immune response while in plants, NO is essential for development and responses to biotic and abiotic stresses [1–3]. Interestingly, NO is involved in the sexual reproduction of both animals and plants mediating physiological events related to the male gamete [2, 4]. In animals, NO stimulates sperm motility [4] and binding to the plasma membrane of oocytes [5] while in plants, NO mediates pollen-stigma interactions and pollen tube guidance [6, 7]. NO generation in pollen tubes (PTs) has been demonstrated [8] and intracellular responses to NO include cytosolic Ca2+ elevation, actin organization, vesicle trafficking and cell wall deposition [7, 9]. However, the NO-responsive proteins that mediate these responses are still elusive. Here we show that PTs of Arabidopsis lacking the pollen-specific Diacylglycerol Kinase 4 (DGK4) grow slower and become insensitive to NO-dependent growth inhibition and re-orientation responses. Recombinant DGK4 protein yields NO-responsive spectral and catalytic changes in vitro which are compatible with a role in NO perception and signaling in PTs. NO is a fast, diffusible gas and, based on our results, we hypothesize it could serve in long range signaling and/or rapid cell-cell communication functions mediated by DGK4 downstream signaling during the progamic phase of angiosperm reproduction.

Glutamate receptor-like channels (GLRs) play important roles in numerous plant physiological processes. GLRs are homologous to ionotropic glutamate receptors (iGluRs) that mediate neurotransmission in vertebrates. Here we determine crystal structures of Arabidopsis thaliana GLR3.2 ligand-binding domain (LBD) in complex with glycine and methionine to 1.58- and 1.75-Å resolution, respectively. Our structures show a fold similar to that of iGluRs, but with several secondary structure elements either missing or different. The closed clamshell conformation of GLR3.2 LBD suggests that both glycine and methionine act as agonists. The mutation R133A strongly increases the constitutive activity of the channel, suggesting that the LBD mutated at the residue critical for agonist binding produces a more stable closed clamshell conformation. Furthermore, our structures explain the promiscuity of GLR activation by different amino acids, confirm evolutionary conservation of structure between GLRs and iGluRs, and predict common molecular principles of their gating mechanisms driven by bilobed clamshell-like LBDs.

Premise of the study Upon pollination, dehydrated pollen grains take water out of the stigma surface, an event that constitutes the first functional checkpoint of sexual reproduction in higher plants. Little is known about possible functional connections between rehydration speed and further steps of fertilization. Here we addressed the mechanisms of water uptake control by dehydrated pollen grains. Because dehydrated cells have no energy-driven active mechanism such as membrane-based osmoregulation for controlling water movement, we tested the hypothesis that another mechanism might exist, namely, the use of hydrogel-behaving molecules. Methods We developed an imaging protocol to visualize and quantify the rate of water entry into pollen grains of Eucalyptus globulus and tested the influence of different treatments linked to hydrogel-behaving molecules. We complemented these analyses by immunostaining pectins in the pollen grain with monoclonal antibodies JIM5 and JIM7. Key results Water entry seemed to proceed exclusively through the germination apertures of the pollen grain, and the changes observed in different hydration media are compatible with hydrogel behavior. When JIM5 and JIM7 were used to characterize pectins on the germination apertures during hydration, pectin localization and esterification changed during hydration and were affected by the hydration solutions. These results suggest that chemical modification of the pectins may change their hydrogel behavior, thus modifying the hydration speed. Conclusions The hydrogel behavior of pectins and pectin localization on apertures strongly suggest that pectins act like "valves" for water entry, enabling a regulated process of water uptake into the dehydrated pollen grain. We propose that this regulation evolved in terms of achieving the correct self-organization of molecules and cellular components to resume metabolism and pollen tube growth, especially in species that are subject to demanding environmental water stress.

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We investigated the molecular basis and physiological implications of anion transport during pollen tube (PT) growth in Arabidopsis thaliana (Col-0). Patch-clamp whole-cell configuration analysis of pollen grain protoplasts revealed three subpopulations of anionic currents differentially regulated by cytoplasmic calcium ([Ca

GESTAO DO JUDICIARIO E GESTAO DA QUALIDADE: UMA QUESTAO DE PRINCIPIOS Resumo: O objetivo deste artigo e contribuir ao debate acerca da gestao do Poder Judiciario tendo como referencia o principio constitucional da eficiencia na administracao publica e os principios da gestao da qualidade. Sob esse enfoque sao abordados os temas da crise na administracao publica e na administracao judiciaria. Atraves de uma revisao bibliografica em livros e artigos levantou-se as contribuicoes de autores sobre o tema em analise. Uma correlacao entre os principios da qualidade e a realidade encontrada na administracao de unidades judiciarias, atraves das fontes analisadas para o estudo, e realizada com o fim de demonstrar a validade da aplicacao dos principios para nortear as mudancas necessarias para a melhoria da prestacao jurisdicional e a aumentar a satisfacao da sociedade. O artigo apresenta a aplicabilidade de um sistema de gestao da qualidade, conforme o modelo da norma ABNT NBR ISO 9001:2015, como uma alternativa eficaz para que o Poder Judiciario apresente a resposta mais adequada para a necessidade de melhoria na eficiencia da gestao do Poder Judiciario. Palavras-chaves: Administracao Publica. Gestao. Judiciario. Eficiencia. Qualidade. JUDICIARY MANAGEMENT AND QUALITY MANAGEMENT: A QUESTION OF PRINCIPLES Abstract: The purpose of this article is to contribute to the debate about the management of the Judiciary having as point of reference the constitutional principle of efficiency in the Public Administration and the principles of quality management. This approach addresses the issues of crisis in the public administration and judicial administration. Through a bibliographical review in books and articles the contributions of authors on the subject under analysis were compiled. A correlation between the principles of quality and the reality found in the management of judicial units, through the sources analyzed for the study, is established in order to demonstrate the validity of the application of the principles to guide the changes necessary to improve the jurisdictional performance and to increase the satisfaction of society. The article presents the applicability of a quality management system, according to the model of ABNT NBR ISO 9001: 2015, as an effective alternative for the Judiciary to provide the most appropriate response to the need of improving the efficiency of the Judiciary management. Keywords: Public Administration. Management. Judiciary. Efficiency. Quality. Data da submissao: 22/08/2018 Data da aprovacao: 01/12/2018

GESTÃO DO JUDICIÁRIO E GESTÃO DA QUALIDADE: UMA QUESTÃO DE PRINCÍPIOS Resumo: O objetivo deste artigo é contribuir ao debate acerca da gestão do Poder Judiciário tendo como referência o princípio constitucional da eficiência na administração pública e os princípios da gestão da qualidade. Sob esse enfoque são abordados os temas da crise na administração pública e na administração judiciária. Através de uma revisão bibliográfica em livros e artigos levantou-se as contribuições de autores sobre o tema em análise. Uma correlação entre os princípios da qualidade e a realidade encontrada na administração de unidades judiciárias, através das fontes analisadas para o estudo, é realizada com o fim de demonstrar a validade da aplicação dos princípios para nortear as mudanças necessárias para a melhoria da prestação jurisdicional e a aumentar a satisfação da sociedade. O artigo apresenta a aplicabilidade de um sistema de gestão da qualidade, conforme o modelo da norma ABNT NBR ISO 9001:2015, como uma alternativa eficaz para que o Poder Judiciário apresente a resposta mais adequada para a necessidade de melhoria na eficiência da gestão do Poder Judiciário.Palavras-chaves: Administração Pública. Gestão. Judiciário. Eficiência. Qualidade.JUDICIARY MANAGEMENT AND QUALITY MANAGEMENT: A QUESTION OF PRINCIPLESAbstract: The purpose of this article is to contribute to the debate about the management of the Judiciary having as point of reference the constitutional principle of efficiency in the Public Administration and the principles of quality management. This approach addresses the issues of crisis in the public administration and judicial administration. Through a bibliographical review in books and articles the contributions of authors on the subject under analysis were compiled. A correlation between the principles of quality and the reality found in the management of judicial units, through the sources analyzed for the study, is established in order to demonstrate the validity of the application of the principles to guide the changes necessary to improve the jurisdictional performance and to increase the satisfaction of society. The article presents the applicability of a quality management system, according to the model of ABNT NBR ISO 9001: 2015, as an effective alternative for the Judiciary to provide the most appropriate response to the need of improving the efficiency of the Judiciary management.Keywords: Public Administration. Management. Judiciary. Efficiency. Quality.Data da submissão: 22/08/2018 Data da aprovação: 01/12/2018

We investigated the molecular basis and physiological implications of anion transport during pollen tube (PT) growth in Arabidopsis thaliana (Col-0). Patch-clamp whole-cell configuration analysis of pollen grain protoplasts revealed three subpopulations of anionic currents differentially regulated by cytoplasmic calcium ([Ca2+ ]cyt ). We investigated the pollen-expressed proteins AtSLAH3, AtALMT12, AtTMEM16 and AtCCC as the putative anion transporters responsible for these currents. AtCCC-GFP was observed at the shank and AtSLAH3-GFP at the tip and shank of the PT plasma membrane. Both are likely to carry the majority of anion current at negative potentials, as extracellular anionic fluxes measured at the tip of PTs with an anion vibrating probe were significantly lower in slah3-/- and ccc-/- mutants, but unaffected in almt12-/- and tmem16-/- . We further characterised the effect of pH and GABA by patch clamp. Strong regulation by extracellular pH was observed in the wild-type, but not in tmem16-/- . Our results are compatible with AtTMEM16 functioning as an anion/H+ cotransporter and therefore, as a putative pH sensor. GABA presence: (1) inhibited the overall currents, an effect that is abrogated in the almt12-/- and (2) reduced the current in AtALMT12 transfected COS-7 cells, strongly suggesting the direct interaction of GABA with AtALMT12. Our data show that AtSLAH3 and AtCCC activity is sufficient to explain the major component of extracellular anion fluxes, and unveils a possible regulatory system linking PT growth modulation by pH, GABA, and [Ca2+ ]cyt through anionic transporters. info:eu-repo/semantics/publishedVersion