The calcium-permeable channel OSCA1.3 regulates plant stomatal immunity.

Perception of biotic and abiotic stresses often leads to stomatal closure in plants1,2. Rapid influx of calcium ions (Ca2+) across the plasma membrane has an important role in this response, but the identity of the Ca2+ channels involved has remained elusive3,4. Here we report that the Arabidopsis thaliana Ca2+-permeable channel OSCA1.3 controls stomatal closure during immune signalling. OSCA1.3 is rapidly phosphorylated upon perception of pathogen-associated molecular patterns (PAMPs). Biochemical and quantitative phosphoproteomics analyses reveal that the immune receptor-associated cytosolic kinase BIK1 interacts with and phosphorylates the N-terminal cytosolic loop of OSCA1.3 within minutes of treatment with the peptidic PAMP flg22, which is derived from bacterial flagellin. Genetic and electrophysiological data reveal that OSCA1.3 is permeable to Ca2+, and that BIK1-mediated phosphorylation on its N terminus increases this channel activity. Notably, OSCA1.3 and its phosphorylation by BIK1 are critical for stomatal closure during immune signalling, and OSCA1.3 does not regulate stomatal closure upon perception of abscisic acid-a plant hormone associated with abiotic stresses. This study thus identifies a plant Ca2+ channel and its activation mechanisms underlying stomatal closure during immune signalling, and suggests specificity in Ca2+ influx mechanisms in response to different stresses.

Publisher Correction: The calcium-permeable channel OSCA1.3 regulates plant stomatal immunity.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

A novel mutant allele of AtCNGC15 reveals a dual function of nuclear calcium release in the root meristem.

Calcium release to the nucleoplasm of root meristem cells was demonstrated to modulate root development. The calcium channel encoded by cyclic nucleotide-gated channel (CNGC) 15 localizes at the nuclear envelope in young Arabidopsis seedlings. In contrast, at later stages of root growth, overexpression analysis showed that AtCNGC15 can relocalize to the plasma membrane to mediate primary nitrate-induced gene expression. This raises the question as to whether nuclear localized AtCNGC15 is required for root apical meristem development in young Arabidopsis seedlings, and whether nitrate signalling occurs independently of nuclear localized AtCNGC15 at this developmental stage. In this study, we characterize a novel mutant allele of AtCNGC15 and demonstrate that the mutation of a highly conserved aspartic acid in the C-linker domain is sufficient to impair the gating of AtCNCG15. We demonstrate that AtCNGC15 mediates the nuclear calcium release that modulates root apical meristem development and nitrate-induced LBD39 expression. We also show that, in the presence of nitrate, the relocalization of AtCNGC15 at the plasma membrane occurs specifically in the columella cells. Our results further suggest that the induction of LBD37, LBD38, and LBD39 in the presence of nitrate is modulated by different inputs of cytoplasmic or nuclear calcium release.

The carbon dioxide neutralizing effect of energy innovation on international tourism in EU-5 countries under the prism of the EKC hypothesis.

Mitigation of carbon dioxide emissions has become an utmost important global agenda, keeping into consideration the associated environmental hardships. As a result, it is important to unearth the factors which can neutralize carbon emissions to transform the world economy into a low-carbon one. Against this backdrop, this study explores the carbon dioxide neutralizing effects of economic growth, international tourism, clean energy promotion, and technological innovation in the context of five European Union (EU-5) nations during the 1990-2015 period. This study's main contribution is in terms of its approach to test the interaction effect between foreign direct investment (FDI) inflows and energy innovation on carbon dioxide emissions. The econometric analysis chronologically involves the employment of unit root, cointegration, causality, and regression methods. Overall, the findings support the inverted-U-shaped economic growth-carbon dioxide emissions nexus to verify the Environmental Kuznets Curve (EKC) hypothesis. Besides, the Pollution Haven Hypothesis in the context of the selected panel is also verified as higher FDI inflows are seen to boost the carbon dioxide emission levels. The results also confirm that energy innovation moderates the harmful effect of air transport (a proxy for international tourism) on carbon dioxide emissions during the developing stage of the tourism industry. On the other hand, renewable energy promotion is found to curb carbon dioxide emissions. These findings suggest that the European governments need to enhance investments in their respective renewable energy sectors and simultaneously ensure the development of clean industries, which can collectively help these nations become carbon-neutral in the future.

Rubisco small subunits from the unicellular green alga Chlamydomonas complement Rubisco-deficient mutants of Arabidopsis.

Introducing components of algal carbon concentrating mechanisms (CCMs) into higher plant chloroplasts could increase photosynthetic productivity. A key component is the Rubisco-containing pyrenoid that is needed to minimise CO2 retro-diffusion for CCM operating efficiency. Rubisco in Arabidopsis was re-engineered to incorporate sequence elements that are thought to be essential for recruitment of Rubisco to the pyrenoid, namely the algal Rubisco small subunit (SSU, encoded by rbcS) or only the surface-exposed algal SSU α-helices. Leaves of Arabidopsis rbcs mutants expressing 'pyrenoid-competent' chimeric Arabidopsis SSUs containing the SSU α-helices from Chlamydomonas reinhardtii can form hybrid Rubisco complexes with catalytic properties similar to those of native Rubisco, suggesting that the α-helices are catalytically neutral. The growth and photosynthetic performance of complemented Arabidopsis rbcs mutants producing near wild-type levels of the hybrid Rubisco were similar to those of wild-type controls. Arabidopsis rbcs mutants expressing a Chlamydomonas SSU differed from wild-type plants with respect to Rubisco catalysis, photosynthesis and growth. This confirms a role for the SSU in influencing Rubisco catalytic properties.

Practical deployment of automation to expedite aqueous two-phase extraction.

The feasibility of bioprocess development relies heavily on the successful application of primary recovery and purification techniques. Aqueous two-phase extraction (ATPE) disrupts the definition of "unit operation" by serving as an integrative and intensive technique that combines different objectives such as the removal of biomass and integrated recovery and purification of the product of interest. The relative simplicity of processing large samples renders this technique an attractive alternative for industrial bioprocessing applications. However, process development is hindered by the lack of easily predictable partition behaviours, the elucidation of which necessitates a large number of experiments to be conducted. Liquid handling devices can assist to address this problem; however, they are configured to operate using low viscosity fluids such as water and water-based solutions as opposed to highly viscous polymeric solutions, which are typically required in ATPE. In this work, an automated high throughput ATPE process development framework is presented by constructing phase diagrams and identifying the binodal curves for PEG6000, PEG3000, and PEG2000. Models were built to determine viscosity- and volume-independent transfer parameters. The framework provided an appropriate strategy to develop a very precise and accurate operation by exploiting the relationship between different liquid transfer parameters and process error. Process accuracy, measured by mean absolute error, and device precision, evaluated by the coefficient of variation, were both shown to be affected by the mechanical properties, particularly viscosity, of the fluids employed. For PEG6000, the mean absolute error improved by six-fold (from 4.82% to 0.75%) and the coefficient of variation improved by three-fold (from 0.027 to 0.008) upon optimisation of the liquid transfer parameters accounting for the viscosity effect on the PEG-salt buffer utilising ATPE operations. As demonstrated here, automated liquid handling devices can serve to streamline process development for APTE enabling wide adoption of this technique in large scale bioprocess applications.

Revisiting the effects of energy, population, foreign direct investment, and economic growth in Visegrad countries under the EKC scheme.

This research studied the impacts of the environmental Kuznets curve and the determinants of economic growth for Visegrad countries from 1990 to 2018. This paper reflects on the effects of renewable and non-renewable energy, urban population, foreign direct investment, economic growth, and carbon dioxide emissions. According to our results, the panel of unit root tests showed that the variables under study are integrated into the first differences. Considering the empirical results for the environmental Kuznets curve, we observe that economic growth is positively correlated with pollution emissions; nevertheless, the squared income per capita is negatively impacted by carbon dioxide emissions. Energy consumption increases carbon emissions, and foreign direct investment confirms the pollution halo hypothesis. Therefore, the econometric results showed that renewable energy consumption promotes regional growth. Consequently, urban population and foreign direct investment positively correlate with economic growth.

Revisiting Marginal Intra-Industry Trade and Portuguese Labour Market.

OBJECTIVES: This study aims to empirically test the smooth adjustment hypothesis (SAH) in the Portuguese labour market during 2000-2018, considering changes in employment, wage, productivity, consumption and the marginal intra-industry trade. RESEARCH DESIGN: So, following the literature, a greater marginal intra-industry trade intensity should reduce adverse shocks expressed in temporary inefficiencies such as undesirable job search costs and workers' relocation and retraining. According to state of the art, our research strategy considered a battery of diagnosis tests about the random generating process of variables included in a dynamic panel data model. METHODS: The extensive work developed in this paper is a further step to introduce recent techniques such as the Method of Moments Quantile Regression and the cointegration panel models to infer long-term dynamics. RESULTS AND CONCLUSIONS: Overall, the main point is that we find evidence confirming the hypothesis mentioned above, showing that mutual interactions reduce adverse shocks above mentioned. Thus, the study demonstrates that the marginal intra-industry trade promotes smooth adjustment in the Portuguese economy.

INTEGRALL: a database and search engine for integrons, integrases and gene cassettes.

INTEGRALL is a freely available, text-based search system developed with the aim of collecting and organizing information on integrons in a single database. The current release (1.2) contains more than 4800 integron sequences and provides a public genetic repository for sequence data and nomenclature, offering scientists an easy and interactive access to integron's DNA sequences, their molecular arrangements as well as their genetic contexts.

The role of tourism, trade, renewable energy use and carbon dioxide emissions on economic growth: evidence of tourism-led growth hypothesis in EU-28.

The article examines the effects of renewable energy, trade, carbon dioxide emissions and international tourism on economic growth in EU-28, considering panel data for the period 1995-2014. The investigation finds the new determinants of economic growth. The empirical results find support from the panel fully modified least squares (FMOLS), panel dynamic least squares (DOLS) and fixed effects (FE) as estimation techniques. The econometric results are consistent with the existing literature. The variables considered in this study are cointegrated in the first difference, as suggested by the panel unit root test. The present study seeks to advance the knowledge of the growth determinants, paying attention to the effect that both the tourism and energy sector exerts on economic growth for EU-28 countries. The empirical results demonstrate that trade openness, tourism arrivals and renewable energy encourage economic growth. Therefore, according to the econometric results, renewable energy allows improving environmental quality. However, CO2 emissions are positively correlated with economic growth, showing that growth is directly correlated by climate change and greenhouse gas. The results also confirm the tourism-led growth hypothesis (TLGH) for the panel. Finally, the empirical results confirm that trade openness, energy use and international tourism contribute to enhance economic growth. Based on these findings, further insights and policy prescription are offered in the concluding section.Graphical abstract.

Nuclear calcium signatures are associated with root development.

In plants, nuclear Ca2+ releases are essential to the establishment of nitrogen-fixing and phosphate-delivering arbuscular mycorrhizal endosymbioses. In the legume Medicago truncatula, these nuclear Ca2+ signals are generated by a complex of nuclear membrane-localised ion channels including the DOES NOT MAKE INFECTIONS 1 (DMI1) and the cyclic nucleotide-gated channels (CNGC) 15s. DMI1 and CNCG15s are conserved among land plants, suggesting roles for nuclear Ca2+ signalling that extend beyond symbioses. Here we show that nuclear Ca2+ signalling initiates in the nucleus of Arabidopsis root cells and that these signals are correlated with primary root development, including meristem development and auxin homeostasis. In addition, we demonstrate that altering genetically AtDMI1 is sufficient to modulate the nuclear Ca2+ signatures, and primary root development. This finding supports the postulate that stimulus-specific information can be encoded in the frequency and duration of a Ca2+ signal and thereby regulate cellular function.

Dual Color Sensors for Simultaneous Analysis of Calcium Signal Dynamics in the Nuclear and Cytoplasmic Compartments of Plant Cells.

Spatiotemporal changes in cellular calcium (Ca2+) concentrations are essential for signal transduction in a wide range of plant cellular processes. In legumes, nuclear and perinuclear-localized Ca2+ oscillations have emerged as key signatures preceding downstream symbiotic signaling responses. Förster resonance energy transfer (FRET) yellow-based Ca2+ cameleon probes have been successfully exploited to measure the spatiotemporal dynamics of symbiotic Ca2+ signaling in legumes. Although providing cellular resolution, these sensors were restricted to measuring Ca2+ changes in single subcellular compartments. In this study, we have explored the potential of single fluorescent protein-based Ca2+ sensors, the GECOs, for multicolor and simultaneous imaging of the spatiotemporal dynamics of cytoplasmic and nuclear Ca2+ signaling in root cells. Single and dual fluorescence nuclear and cytoplasmic-localized GECOs expressed in transgenic Medicago truncatula roots and Arabidopsis thaliana were used to successfully monitor Ca2+ responses to microbial biotic and abiotic elicitors. In M. truncatula, we demonstrate that GECOs detect symbiosis-related Ca2+ spiking variations with higher sensitivity than the yellow FRET-based sensors previously used. Additionally, in both M. truncatula and A. thaliana, the dual sensor is now able to resolve in a single root cell the coordinated spatiotemporal dynamics of nuclear and cytoplasmic Ca2+ signaling in vivo. The GECO-based sensors presented here therefore represent powerful tools to monitor Ca2+ signaling dynamics in vivo in response to different stimuli in multi-subcellular compartments of plant cells.

Frequency of blood type A, B, and AB in 515 domestic shorthair cats from the Lisbon area.

BACKGROUND: The A, B, and AB feline blood types are recognized worldwide and their frequencies vary geographically and among breeds. Frequencies of feline blood types have been reported previously from northern Portugal; however, they are unknown in other parts of the country. OBJECTIVES: This 13-year retrospective study was undertaken to determine the frequency of feline blood types in domestic shorthair (DSH) cats from the Lisbon area of central Portugal. METHODS: Blood samples were obtained at the Veterinary Teaching Hospital of the Technical University of Lisbon and its Veterinary Blood Bank and at several veterinary clinics in the Lisbon area. Blood-typing was performed by the classical agglutination assay or using a cartridge assay. RESULTS: The study population comprised 515 DSH cats of both sexes and various ages. Frequencies of blood types A, B, and AB were 97.5%, 2.1%, and 0.4%, respectively. CONCLUSION: As in other parts of the world, this study showed a clear predominance of type-A cats in the Lisbon area of Portugal.