Publications by authors named "José Pardo"

141 Publications

[Acute myocardial infarction caused by thrombosis of left main coronary artery. Report of two cases].

Rev Med Chil 2020 Oct;148(10):1508-1512

Hospital Militar de Santiago, Chile.

Acute myocardial infarction caused by thrombosis of left main coronary artery generate acute cardiac failure, cardiogenic shock and death. Along with the clinical history, the electrocardiogram (EKG) is the most useful tool for its recognition and timely management. Classically the EKG shows ST elevation > 1 mm in aVR or V1 with ST depression in the other leads. Urgent coronary angiography with percutaneous coronary angioplasty using drug eluting stents is recommended when the diagnosis is made. We report two cases to exemplify the clinical presentation, EKG and angiographic findings and therapeutic approach.
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http://dx.doi.org/10.4067/S0034-98872020001001508DOI Listing
October 2020

The role of PQL genes in response to salinity tolerance in and barley.

Plant Direct 2021 Feb 10;5(2):e00301. Epub 2021 Feb 10.

Division of Biological and Environmental Sciences and Engineering King Abdullah University of Science and Technology Thuwal Kingdom of Saudi Arabia.

While soil salinity is a global problem, how salt enters plant root cells from the soil solution remains underexplored. Non-selective cation channels (NSCCs) are suggested to be the major pathway for the entry of sodium ions (Na), yet their genetic constituents remain unknown. Yeast PQ loop (PQL) proteins were previously proposed to encode NSCCs, but the role of PQLs in plants is unknown. The hypothesis tested in this research is that PQL proteins constitute NSCCs mediating some of the Na influx into the root, contributing to ion accumulation and the inhibition of growth in saline conditions. We identified plant PQL homologues, and studied the role of one clade of PQL genes in Arabidopsis and barley. Using heterologous expression of and in HEK293 cells allowed us to resolve sizable inwardly directed currents permeable to monovalent cations such as Na, K, or Li upon membrane hyperpolarization. We observed that GFP-tagged PQL proteins localized to intracellular membrane structures, both when transiently over-expressed in tobacco leaf epidermis and in stable Arabidopsis transformants. Expression of , and was increased by salt stress in the shoot tissue compared to non-stressed plants. Mutant lines with altered expression of and developed larger rosettes in saline conditions, while altered levels of AtPQL1a severely reduced development of lateral roots in all conditions. This study provides the first step toward understanding the function of PQL proteins in plants and the role of NSCC in salinity tolerance.
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http://dx.doi.org/10.1002/pld3.301DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7876507PMC
February 2021

Insights into the Mechanisms of Transport and Regulation of the Arabidopsis High-affinity K+ Transporter HAK51.

Plant Physiol 2021 Jan 29. Epub 2021 Jan 29.

Departamento de Nutrición Vegetal, Centro de Edafología y Biología Aplicada del Segura, Consejo Superior de Investigaciones Científicas, Campus de Espinardo, 30100 Murcia, Spain.

The high-affinity K+ transporter HAK5 from Arabidopsis (Arabidopsis thaliana) is essential for K+ acquisition and plant growth at low micromolar K+ concentrations. Despite its functional relevance in plant nutrition, information about functional domains of HAK5 is scarce. Its activity is enhanced by phosphorylation via the AtCIPK23/AtCBL1-9 complex. Based on the recently published three-dimensionalstructure of the bacterial ortholog KimA from Bacillus subtilis, we have modeled AtHAK5 and, by a mutational approach, identified residues G67, Y70, G71, D72, D201, and E312 as essential for transporter function. According to the structural model, residues D72, D201, and E312 may bind K+, whereas residues G67, Y70, and G71 may shape the selective filter for K+, which resembles that of K+shaker-like channels. In addition, we show that phosphorylation of residue S35 by AtCIPK23 is required for reaching maximal transport activity. Serial deletions of the AtHAK5 C-terminus disclosed the presence of an autoinhibitory domain located between residues 571 and 633 together with an AtCIPK23-dependent activation domain downstream of position 633. Presumably, autoinhibition of AtHAK5 is counteracted by phosphorylation of S35 by AtCIPK23. Our results provide a molecular model for K+ transport and describe CIPK-CBL-mediated regulation of plant HAK transporters.
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http://dx.doi.org/10.1093/plphys/kiab028DOI Listing
January 2021

[Type I Brugada electrocardiographic pattern associated with Influenza B and fever. Report of a case].

Rev Med Chil 2020 Sep;148(9):1368-1370

Unidad Coronaria, Hospital Militar de Santiago, Santiago, Chile.

We report a 44-year-old male who was admitted for Influenza B and fever, presenting a type I Brugada pattern on the electrocardiogram. He evolved without cardiovascular symptoms. The pharmacological test with intravenous Procainamide reproduced type I Brugada pattern and the programmed electrical stimulation was negative for ventricular arrhythmias. He was discharged without incidents. Clinical aspects of Brugada syndrome and the importance of fever are discussed in the current context of the COVID-19 pandemic.
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http://dx.doi.org/10.4067/S0034-98872020000901368DOI Listing
September 2020

HOS15 is a transcriptional corepressor of NPR1-mediated gene activation of plant immunity.

Proc Natl Acad Sci U S A 2020 12 16;117(48):30805-30815. Epub 2020 Nov 16.

Department of Biomedical Science and Engineering, Konkuk University, 05029 Seoul, South Korea;

Transcriptional regulation is a complex and pivotal process in living cells. HOS15 is a transcriptional corepressor. Although transcriptional repressors generally have been associated with inactive genes, increasing evidence indicates that, through poorly understood mechanisms, transcriptional corepressors also associate with actively transcribed genes. Here, we show that HOS15 is the substrate receptor for an SCF/CUL1 E3 ubiquitin ligase complex (SCF) that negatively regulates plant immunity by destabilizing transcriptional activation complexes containing NPR1 and associated transcriptional activators. In unchallenged conditions, HOS15 continuously eliminates NPR1 to prevent inappropriate defense gene expression. Upon defense activation, HOS15 preferentially associates with phosphorylated NPR1 to stimulate rapid degradation of transcriptionally active NPR1 and thus limit the extent of defense gene expression. Our findings indicate that HOS15-mediated ubiquitination and elimination of NPR1 produce effects contrary to those of CUL3-containing ubiquitin ligase that coactivate defense gene expression. Thus, HOS15 plays a key role in the dynamic regulation of pre- and postactivation host defense.
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http://dx.doi.org/10.1073/pnas.2016049117DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7720166PMC
December 2020

Review about Non-Lipid Components and Minor Fat-Soluble Bioactive Compounds of Almond Kernel.

Foods 2020 Nov 11;9(11). Epub 2020 Nov 11.

Higher Technical School of Agricultural and Forestry Engineering, University of Castilla-La Mancha, Campus Universitario, s/n, 02071 Albacete, Spain.

This work presents a bibliographic review about almond kernel non-lipid components, in particular about the protein fraction, the carbohydrates and the mineral fraction. In addition, other fat-soluble phytochemicals which are present in minor concentrations but show important antioxidant activities are reviewed. Almond kernel is a rich protein food (8.4-35.1%), in which the globulin-albumin fraction dominates, followed by glutelins and prolamins. Within the almond kernel protein profile, amandine dominates. Free amino acids represent a small amount of the total nitrogen quantity, highlighting the presence of glutamic acid and aspartic acid, followed by arginine. Carbohydrates that appear in almond kernels (14-28%) are soluble sugars (mainly sucrose), starch and other polysaccharides such as cellulose and non-digestible hemicelluloses. Regarding the mineral elements, potassium is the most common, followed by phosphorus; both macronutrients represent more than 70% of the total mineral fraction, without taking into account nitrogen. Microminerals include sodium, iron, copper, manganese and zinc. Within the phytochemical compounds, tocopherols, squalene, phytosterols, stanols, sphingolipids, phospholipids, chlorophylls, carotenoids, phenols and volatile compounds can be found.
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http://dx.doi.org/10.3390/foods9111646DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7697880PMC
November 2020

Beyond the patch-clamp resolution: functional activity of nonelectrogenic vacuolar NHX proton/potassium antiporters and inhibition by phosphoinositides.

New Phytol 2021 03 29;229(5):3026-3036. Epub 2020 Nov 29.

Institute of Biophysics, National Research Council, Via De Marini 6, Genova, 16149, Italy.

We combined the patch-clamp technique with ratiometric fluorescence imaging using the proton-responsive dye BCECF as a luminal probe. Upon application of a steep cytosol-directed potassium ion (K ) gradient in Arabidopsis mesophyll vacuoles, a strong and reversible acidification of the vacuolar lumen was detected, whereas no associated electrical currents were observed, in agreement with electroneutral cation/H exchange. Our data show that this acidification was generated by NHX antiport activity, because: it did not distinguish between K and sodium (Na ) ions; it was sensitive to the NHX inhibitor benzamil; and it was completely absent in vacuoles from nhx1 nhx2 double knockout plants. Our data further show that NHX activity could be reversed, was voltage-independent and specifically impaired by the low-abundance signaling lipid PI(3,5)P , which may regulate salt accumulation in plants by acting as a common messenger to coordinately shut down secondary active carriers responsible for cation and anion uptake inside the vacuole. Finally, we developed a theory based on thermodynamics, which supports the data obtained by our novel experimental approach. This work, therefore, represents a proof-of-principle that can be applied to the study of proton-dependent exchangers from plants and animals, which are barely detectable using conventional techniques.
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http://dx.doi.org/10.1111/nph.17021DOI Listing
March 2021

From By-Product to the Food Chain: Melon ( L.) Seeds as Potential Source for Oils.

Foods 2020 Sep 23;9(10). Epub 2020 Sep 23.

Higher Technical School of Agricultural and Forestry Engineering, University of Castilla-La Mancha, Campus Universitario s/n, 02071 Albacete, Spain.

Fruit-processing industries annually discard large volumes of fruit by-products. Thousands of tons of melon seeds could be recovered through the year from melon production. These seeds are an excellent source of vegetable oil with significant health-promoting properties due to their unsaturated fatty acid profile and high content of specific bioactive compounds. However, little information exists about the influence of melon cultivars and oil-extraction methods on oil characteristics. In this study, oils from nine different melon cultivars were evaluated. Additionally, two oil-extraction methods (screw and hydraulic press) were studied. Results showed that melon seeds may be used as a novel source of healthy oils. Higher-quality oils were obtained with the hydraulic press; however, low yields reduced industrial interest in this method. Oils extracted from the different cultivars showed high variability in the content of linoleic (51-69%) and oleic (15-34%) acids. Regarding vitamin E, γ-tocopherol was the main isoform found in melon-seed oils (99.81-456.73 mg/kg), followed by α- and δ-tocopherols. Significant concentrations of tocotrienols (α, β, and γ) were also found. Although all cultivars showed positive attributes, principal-component analysis (PCA) showed that Honey Dew and Blanco de Ribatejo could be specifically considered as a potential source of polyunsaturated oils with high concentrations of vitamin E.
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http://dx.doi.org/10.3390/foods9101341DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7598262PMC
September 2020

The Histone-Modifying Complex PWR/HOS15/HD2C Epigenetically Regulates Cold Tolerance.

Plant Physiol 2020 10 30;184(2):1097-1111. Epub 2020 Jul 30.

Department of Biomedical Science and Engineering, Konkuk University, Seoul 05029, Republic of Korea

Cold stress is a major environmental stress that severely affects plant growth and crop productivity. Arabidopsis () HIGH EXPRESSION OF OSMOTICALLY RESPONSIVE GENE15 (HOS15) is a substrate receptor of the CULLIN4-based CLR4 ubiquitin E3 ligase complex, which epigenetically regulates cold tolerance by degrading HISTONE DEACETYLASE2C (HD2C) to switch from repressive to permissive chromatin structure in response to cold stress. In this study, we characterized a HOS15-binding protein, POWERDRESS (PWR), and analyzed its function in the cold stress response. PWR loss-of-function plants () showed lower expression of cold-regulated () genes and sensitivity to freezing. PWR interacts with HD2C through HOS15, and cold-induced HD2C degradation by HOS15 is diminished in the mutant. The association of HOS15 and HD2C to promoters of cold-responsive genes was dependent on PWR. Consistent with these observations, the high acetylation levels of histone H3 by cold-induced and HOS15-mediated HD2C degradation were significantly reduced in under cold stress. PWR also interacts with C-repeat element-binding factor transcription factors to modulate their cold-induced binding to the promoter of genes. Collectively, our data signify that the PWR-HOS15-HD2C histone-modifying complex regulates the expression of genes and the freezing tolerance of plants.
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http://dx.doi.org/10.1104/pp.20.00439DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7536694PMC
October 2020

ABAting the Response: A Novel ABA Signal Terminator that Disrupts the Hormone Co-receptor Complex.

Mol Plant 2020 09 24;13(9):1241-1243. Epub 2020 Jul 24.

Department of Biomedical Science & Engineering, Konkuk University, Seoul 05029, South Korea. Electronic address:

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http://dx.doi.org/10.1016/j.molp.2020.07.017DOI Listing
September 2020

The GIGANTEA-ENHANCED EM LEVEL Complex Enhances Drought Tolerance via Regulation of Abscisic Acid Synthesis.

Plant Physiol 2020 09 20;184(1):443-458. Epub 2020 Jul 20.

Department of Biomedical Science and Engineering, Konkuk University, Seoul 05029, Korea

Drought is one of the most critical environmental stresses limiting plant growth and crop productivity. The synthesis and signaling of abscisic acid (ABA), a key phytohormone in the drought stress response, is under photoperiodic control. GIGANTEA (GI), a key regulator of photoperiod-dependent flowering and the circadian rhythm, is also involved in the signaling pathways for various abiotic stresses. In this study, we isolated ENHANCED EM LEVEL (EEL)/basic Leu zipper 12, a transcription factor involved in ABA signal responses, as a GI interactor in Arabidopsis (). The diurnal expression of (), a rate-limiting ABA biosynthetic enzyme, was reduced in the , , and mutants under normal growth conditions. Chromatin immunoprecipitation and electrophoretic mobility shift assays revealed that EEL and GI bind directly to the ABA-responsive element motif in the promoter. Furthermore, the , , and mutants were hypersensitive to drought stress due to uncontrolled water loss. The transcript of , endogenous ABA levels, and stomatal closure were all reduced in the , , and mutants under drought stress. Our results suggest that the EEL-GI complex positively regulates diurnal ABA synthesis by affecting the expression of , and contributes to the drought tolerance of Arabidopsis.
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http://dx.doi.org/10.1104/pp.20.00779DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7479899PMC
September 2020

HKT sodium and potassium transporters in Arabidopsis thaliana and related halophyte species.

Physiol Plant 2021 Apr 23;171(4):546-558. Epub 2020 Jul 23.

Department of Biomedical Science & Engineering, Konkuk University, Seoul, 05029, South Korea.

High salinity induces osmotic stress and often leads to sodium ion-specific toxicity, with inhibitory effects on physiological, biochemical and developmental pathways. To cope with increased Na in soil water, plants restrict influx, compartmentalize ions into vacuoles, export excess Na from the cell, and distribute ions between the aerial and root organs. In this review, we discuss our current understanding of how high-affinity K transporters (HKT) contribute to salinity tolerance, focusing on HKT1-like family members primarily involved in long-distance transport, and in the recent research in the model plant Arabidopsis and its halophytic counterparts of the Eutrema genus. Functional characterization of the salt overly sensitive (SOS) pathway and HKT1-type transporters in these species indicate that they utilize similar approaches to deal with salinity, regardless of their tolerance.
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http://dx.doi.org/10.1111/ppl.13166DOI Listing
April 2021

Evolution of Virgin Olive Oil during Long-term Storage.

J Oleo Sci 2020 Aug 9;69(8):809-814. Epub 2020 Jul 9.

Escuela Técnica Superior de Ingenieros Agrónomos y de Montes. Universidad de Castilla-La Mancha. Campus Universitario.

In this work, the evolution of virgin olive oil from 4 olive varieties when stored at 5°C, 10°C and 20°C for a period of up to 3 years was studied. Free acidity increased progressively for the 4 varieties, staying below the limit for extra virgin olive oil, even at the highest temperature. The peroxide value also increased, reaching its maximum after about 28 months of storage, when some samples stored at 20°C exceeded the limit for extra virgin olive oil. The maximum values for K and K were reached at the end of the storage period, also exceeding the limit for extra virgin olive oil in the case of some varieties stored at 20°C. Oxidative stability decreased by 38%-50% depending on the storage temperature and the variety. Most of the color indexes increased in value because of the degradation of the oil pigments.
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http://dx.doi.org/10.5650/jos.ess19258DOI Listing
August 2020

PWR/HDA9/ABI4 Complex Epigenetically Regulates ABA Dependent Drought Stress Tolerance in .

Front Plant Sci 2020 26;11:623. Epub 2020 May 26.

Department of Biomedical Science and Engineering, Konkuk University, Seoul, South Korea.

Drought stress adversely affects plant growth and development and significantly reduces crop productivity and yields. The phytohormone abscisic acid (ABA) rapidly accumulates in response to drought stress and mediates the expression of stress-responsive genes that help the plant to survive dehydration. The protein Powerdress (PWR), which interacts with Histone Deacetylase 9 (HDA9), has been identified as a critical component regulating plant growth and development, flowering time, floral determinacy, and leaf senescence. However, the role and function of PWR and HDA9 in abiotic stress response had remained elusive. Here we report that a complex of PWR and HDA9 interacts with ABI4 and epigenetically regulates drought signaling in plants. T-DNA insertion mutants of and are insensitive to ABA and hypersensitive to dehydration. Furthermore, the expression of ABA-responsive genes (, , and ) is also downregulated in and mutants. Yeast two-hybrid assays showed that PWR and HDA9 interact with ABI4. Transcript levels of genes that are normally repressed by ABI4, such as , and , are increased in . More importantly, during dehydration stress, PWR and HDA9 regulate the acetylation status of the , which encodes a major enzyme of ABA catabolism. Taken together, our results indicate that PWR, in association with HDA9 and ABI4, regulates the chromatin modification of genes responsible for regulation of both the ABA-signaling and ABA-catabolism pathways in response to ABA and drought stress.
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http://dx.doi.org/10.3389/fpls.2020.00623DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7266079PMC
May 2020

ESCRT-I Component VPS23A Sustains Salt Tolerance by Strengthening the SOS Module in Arabidopsis.

Mol Plant 2020 08 18;13(8):1134-1148. Epub 2020 May 18.

State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing 100101 P. R. China; University of Chinese Academy of Sciences, Beijing 100049, P. R. China. Electronic address:

The Salt-Overly-Sensitive (SOS) signaling module, comprising the sodium-transport protein SOS1 and the regulatory proteins SOS2 and SOS3, is well known as the central salt excretion system, which helps protect plants against salt stress. Here we report that VPS23A, a component of the ESCRT (endosomal sorting complex required for transport), plays an essential role in the function of the SOS module in conferring plant salt tolerance. VPS23A enhances the interaction of SOS2 and SOS3. In the presence of salt stress, VPS23A positively regulates the redistribution of SOS2 to the plasma membrane, which then activates the antiporter activity of SOS1 to reduce Na accumulation in plant cells. Genetic evidence demonstrated that plant salt tolerance achieved by the overexpression of SOS2 and SOS3 dependeds on VPS23A. Taken together, our results revealed that VPS23A is a crucial regulator of the SOS module and affects the localization of SOS2 to the cell membrane. Moreover, the strong salt tolerance of Arabidopsis seedlings conferred by the engineered membrane-bound SOS2 revealed the significance of SOS2 sorting to the cell membrane in achieving its function, providing a potential strategy for crop salt tolerance engineering.
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http://dx.doi.org/10.1016/j.molp.2020.05.010DOI Listing
August 2020

Optimization of cultivation techniques improves the agronomic behavior of Agaricus subrufescens.

Sci Rep 2020 05 18;10(1):8154. Epub 2020 May 18.

Universidade Estadual Paulista (UNESP), Faculdade de Ciências Agrárias e Tecnológicas (FCAT), Dracena, Brazil.

New species of medicinal mushrooms have emerged over the past several decades, such as the Sun mushroom, Agaricus subrufescens. Horticultural improvements are required to shift its cultivation from small-scale local production to large-scale international production. The research reported here evaluated the agronomic behavior and the chemical characteristics of the Sun mushroom as a function of i) nutritional supplementation ii) ruffling of the casing layer and iii) the temperature management on the primordia induction and reduction of the crop cycle. Supplementation was beneficial for yield, unit mushroom weigh and decrease in time to first harvest. Supplementation improved biological efficiency with Champfood providing a yield increase of 15% over the non-supplemented compost. Among the supplements only Promycel increased the individual mushroom weight. Ruffling overall improved the yield in the 2 and 4 flush. Already biological efficiency was greater by 21%. The highest yield harvested in any single day in the crop occurred in 3 flush with the amount of 2.484 kg of mushrooms per m for the rapid induction method. Still the biological efficiency was not significantly affected by the mushroom induction temperature method. Only the fat content of the mushrooms was positively affected by the rapid induction of primordia. Champfood supplement promotes a reduction in the value of earliness and an increase of 1 flush yield. The ruffling technique provided an increase in biological efficiency due to the great number of mushrooms harvested. Rapid primordia induction allowed the crop cycle to end 3 days earlier than the slow primordia induction, providing a higher production rate.
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http://dx.doi.org/10.1038/s41598-020-65081-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7235075PMC
May 2020

Desensitization of ABA-Signaling: The Swing From Activation to Degradation.

Front Plant Sci 2020 22;11:379. Epub 2020 Apr 22.

Department of Biomedical Science and Engineering, Konkuk University, Seoul, South Korea.

Abscisic acid (ABA) is a key plant stress-signaling hormone that accumulates upon osmotic stresses such as drought and high salinity. Several proteins have been identified that constitute the ABA-signaling pathway. Among them ABA receptors (PYR/PYL/RCAR), co-receptor PP2Cs (protein phosphatases), SnRK2 kinases (SNF1-related protein kinases) and ABI5/ABFs (transcription factors) are the major components. Upon ABA signal, PYR/PYL receptors interact with and recruit PP2Cs, releasing SnRK2s kinases from sequestration with PP2Cs. This allows SnKR2s to promote the activation of downstream transcription factors of ABA pathway. However, apart from activation, ubiquitination and degradation of core proteins in the ABA pathway by the ubiquitin proteasome system is less explored. In this review we will focus on the recent findings about feedback regulation of ABA signaling core proteins through degradation, which is emerging as a critical step that modulates and eventually ceases the signal relay. Additionally, we also discuss the importance of the recently identified effector protein HOS15, which negatively regulate ABA-signaling through degradation of OST1.
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http://dx.doi.org/10.3389/fpls.2020.00379DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7188955PMC
April 2020

Observation of unexpected uniaxial magnetic anisotropy in LaSrMnO films by a BaTiO overlayer in an artificial multiferroic bilayer.

Beilstein J Nanotechnol 2020 16;11:651-661. Epub 2020 Apr 16.

Departamento de Física de la Materia Condensada, Universidad de Zaragoza, 50009 Zaragoza, Spain.

We studied in detail the in-plane magnetic properties of heterostructures based on a ferroelectric BaTiO overlayer deposited on a ferromagnetic LaSrMnO film grown epitaxially on pseudocubic (001)-oriented SrTiO, (LaAlO)(SrTaAlO) and LaAlO substrates. In this configuration, the combination of both functional perovskites constitutes an artificial multiferroic system with potential applications in spintronic devices based on the magnetoelectric effect. LaSrMnO single layers and BaTiO/LaSrMnO bilayers using the pulsed-laser deposition technique. We analyzed the films structurally through X-ray reciprocal space maps and high-angle annular dark field microscopy, and magnetically via thermal demagnetization curves and in-plane magnetization versus applied magnetic field loops at room temperature. Our results indicate that the BaTiO layer induces an additional strain in the LaSrMnO layers close to their common interface. The presence of BaTiO on the surface of tensile-strained LaSrMnO films transforms the in-plane biaxial magnetic anisotropy present in the single layer into an in-plane uniaxial magnetic anisotropy. Our experimental evidence suggests that this change in the magnetic anisotropy only occurs in tensile-strained LaSrMnO film and is favored by an additional strain on the LaSrMnO layer promoted by the BaTiO film. These findings reveal an additional mechanism that alters the magnetic behavior of the ferromagnetic layer, and consequently, deserves further in-depth research to determine how it can modify the magnetoelectric coupling of this hybrid multiferroic system.
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http://dx.doi.org/10.3762/bjnano.11.51DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7176924PMC
April 2020

Coordinated Transport of Nitrate, Potassium, and Sodium.

Front Plant Sci 2020 6;11:247. Epub 2020 Mar 6.

Institute of Plant Biochemistry and Photosynthesis, Consejo Superior de Investigaciones Científicas and Universidad de Sevilla, Seville, Spain.

Potassium (K) and nitrogen (N) are essential nutrients, and their absorption and distribution within the plant must be coordinated for optimal growth and development. Potassium is involved in charge balance of inorganic and organic anions and macromolecules, control of membrane electrical potential, pH homeostasis and the regulation of cell osmotic pressure, whereas nitrogen is an essential component of amino acids, proteins, and nucleic acids. Nitrate (NO) is often the primary nitrogen source, but it also serves as a signaling molecule to the plant. Nitrate regulates root architecture, stimulates shoot growth, delays flowering, regulates abscisic acid-independent stomata opening, and relieves seed dormancy. Plants can sense K/NO levels in soils and adjust accordingly the uptake and root-to-shoot transport to balance the distribution of these ions between organs. On the other hand, in small amounts sodium (Na) is categorized as a "beneficial element" for plants, mainly as a "cheap" osmolyte. However, at high concentrations in the soil, Na can inhibit various physiological processes impairing plant growth. Hence, plants have developed specific mechanisms to transport, sense, and respond to a variety of Na conditions. Sodium is taken up by many K transporters, and a large proportion of Na ions accumulated in shoots appear to be loaded into the xylem by systems that show nitrate dependence. Thus, an adequate supply of mineral nutrients is paramount to reduce the noxious effects of salts and to sustain crop productivity under salt stress. In this review, we will focus on recent research unraveling the mechanisms that coordinate the K-NO; Na-NO, and K-Na transports, and the regulators controlling their uptake and allocation.
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http://dx.doi.org/10.3389/fpls.2020.00247DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7067972PMC
March 2020

Recognition and Activation of the Plant AKT1 Potassium Channel by the Kinase CIPK23.

Plant Physiol 2020 04 3;182(4):2143-2153. Epub 2020 Feb 3.

Departamento de Cristalografía y Biología Estructural, Instituto de Química Física "Rocasolano", Consejo Superior de Investigaciones Científicas, E-28006 Madrid, Spain

Plant growth largely depends on the maintenance of adequate intracellular levels of potassium (K). The families of 10 Calcineurin B-Like (CBL) calcium sensors and 26 CBL-Interacting Protein Kinases (CIPKs) of Arabidopsis () decode the calcium signals elicited by environmental inputs to regulate different ion channels and transporters involved in the control of K fluxes by phosphorylation-dependent and -independent events. However, the detailed molecular mechanisms governing target specificity require investigation. Here, we show that the physical interaction between CIPK23 and the noncanonical ankyrin domain in the cytosolic side of the inward-rectifier K channel AKT1 regulates kinase docking and channel activation. Point mutations on this domain specifically alter binding to CIPK23, enhancing or impairing the ability of CIPK23 to regulate channel activity. Our data demonstrate the relevance of this protein-protein interaction that contributes to the formation of a complex between CIPK23/CBL1 and AKT1 in the membrane for the proper regulation of K transport.
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http://dx.doi.org/10.1104/pp.19.01084DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7140914PMC
April 2020

A preliminary study of resting brain metabolism in treatment-resistant depression before and after treatment with olanzapine-fluoxetine combination.

PLoS One 2020 13;15(1):e0226486. Epub 2020 Jan 13.

Department of Psychiatry, University of Minnesota, Minneapolis, Minnesota, United States of America.

Treatment-resistant depression (TRD) occurs in many patients and causes high morbidity and mortality. Because TRD subjects are particularly difficult to study especially longitudinally, biological data remain very limited. In a preliminary study to judge feasibility and power, 25 TRD patients were referred from specialty psychiatric practices. All were severely and chronically depressed and mostly had comorbid psychiatric disorders as is typical in TRD. Nine patients were able to complete all required components of the protocol that included diagnostic interview; rating scales; clinical magnetic resonance imaging; medication washout; treatment with maximally tolerated olanzapine-fluoxetine combination for 8 weeks; and pre- and post-treatment fluorodeoxyglucose positron emission tomography. This drug combination is an accepted standard of treatment for TRD. Dropouts arose from worsening depression, insomnia, and anxiety. One patient remitted; three responded. A priori regions of interest included the amygdala and subgenual cingulate cortex (sgACC; Brodmann area BA25). Responders showed decreased metabolism with treatment in the right amygdala that correlated with clinical response; no significant changes in BA25; better response to treatment the higher the baseline BA25 metabolism; and decreased right ventromedial prefrontal metabolism (VMPFC; broader than BA25) with treatment which did not correlate with depression scores. The baseline metabolism of all individuals showed heterogeneous patterns when compared to a normative metabolic database. Although preliminary given the sample size, this study highlights several issues important for future work: marked dropout rate in this study design; need for large sample size for adequate power; baseline metabolic heterogeneity of TRD requiring careful subject characterization for future studies of interventions; relationship of amygdala activity decreases with response; and the relationship between baseline sgACC and VMPFC activity with response. Successful treatment of TRD with olanzapine-fluoxetine combination shows changes in cerebral metabolism like those seen in treatment-responsive major depression.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0226486PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6957341PMC
April 2020

Rheostatic Control of ABA Signaling through HOS15-Mediated OST1 Degradation.

Mol Plant 2019 11 3;12(11):1447-1462. Epub 2019 Sep 3.

Department of Biomedical Science & Engineering, Konkuk University, Seoul 05029, South Korea. Electronic address:

Dehydrating stresses trigger the accumulation of abscisic acid (ABA), a key plant stress-signaling hormone that activates Snf1-Related Kinases (SnRK2s) to mount adaptive responses. However, the regulatory circuits that terminate the SnRK2s signal relay after acclimation or post-stress conditions remain to be defined. Here, we show that the desensitization of the ABA signal is achieved by the regulation of OST1 (SnRK2.6) protein stability via the E3-ubiquitin ligase HOS15. Upon ABA signal, HOS15-induced degradation of OST1 is inhibited and stabilized OST1 promotes the stress response. When the ABA signal terminates, protein phosphatases ABI1/2 promote rapid degradation of OST1 via HOS15. Notably, we found that even in the presence of ABA, OST1 levels are also depleted within hours of ABA signal onset. The unexpected dynamics of OST1 abundance are then resolved by systematic mathematical modeling, demonstrating a desensitizing feedback loop by which OST1-induced upregulation of ABI1/2 leads to the degradation of OST1. This model illustrates the complex rheostat dynamics underlying the ABA-induced stress response and desensitization.
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http://dx.doi.org/10.1016/j.molp.2019.08.005DOI Listing
November 2019

Use of peanut waste for oyster mushroom substrate supplementation-oyster mushroom and peanut waste.

Braz J Microbiol 2019 Oct 7;50(4):1021-1029. Epub 2019 Aug 7.

Centro de Investigación, Experimentación y Servicios del Champiñón (CIES), Quintanar del Rey, Cuenca, Spain.

The aim of the research was to verify the influence of macro and micronutrients present in the peanut waste (hulls and nuts) for supplementation of Pleurotus ostreatus substrate. The raw materials for base substrate preparation were Brachiaria dictyoneura, sugarcane bagasse (bulk material), rice and wheat bran, calcitic limestone, and gypsum. The following supplement formulations were used as treatments: (1) 100% peanut hulls, (2) 80% peanut hulls + 20% nuts, (3) 60% peanut hulls + 40% nuts, (4) 40% peanut hulls + 60% nuts, (5) 20% peanut hulls + 80% nuts, and (6) 100% nuts. A commercial supplement was also used as an additional treatment. The supplementation was done at spawning using the rates of 1% and 2% wet weight of the substrate. Positive correlations amongst yield and N content, and weight of mushroom and P and K content were verified with 1% supplement. A positive correlation between yield and Cu content, and a negative correlation between yield and Mn content were observed with 2% supplement. The use of peanut waste can be used as supplement for the production of P. ostreatus increasing biological efficiency up to 61%. A better combination can be reached with 20% peanut hulls + 80% nuts or 100% nuts. The addition of 2% supplement in the substrate provided greater yield than 1%.
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http://dx.doi.org/10.1007/s42770-019-00130-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6863277PMC
October 2019

Classification of epileptic EEG recordings using signal transforms and convolutional neural networks.

Comput Biol Med 2019 06 25;109:148-158. Epub 2019 Apr 25.

Speech Technology Group. Center for Information Processing and Telecommunications, E.T.S.I Telecomunicación, UPM, Spain.

This paper describes the analysis of a deep neural network for the classification of epileptic EEG signals. The deep learning architecture is made up of two convolutional layers for feature extraction and three fully-connected layers for classification. We evaluated several EEG signal transforms for generating the inputs to the deep neural network: Fourier, wavelet and empirical mode decomposition. This analysis was carried out using two public datasets (Bern-Barcelona EEG and Epileptic Seizure Recognition datasets) obtaining significant improvements in accuracy. For the Bern-Barcelona EEG, we obtained an increase in accuracy from 92.3% to 98.9% when classifying between focal and non-focal signals using the empirical mode decomposition. For the Epileptic Seizure Recognition dataset, we evaluated several scenarios for seizure detection obtaining the best results when using the Fourier transform. The accuracy increased from 99.0% to 99.5% for classifying non-seizure vs. seizure recordings, from 91.7% to 96.5% when differentiating between healthy, non-focal and seizure recordings, and from 89.0% to 95.7% when considering healthy, focal and seizure recordings.
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http://dx.doi.org/10.1016/j.compbiomed.2019.04.031DOI Listing
June 2019

A Critical Role of Sodium Flux via the Plasma Membrane Na/H Exchanger SOS1 in the Salt Tolerance of Rice.

Plant Physiol 2019 06 16;180(2):1046-1065. Epub 2019 Apr 16.

Instituto de Bioquimica Vegetal y Fotosintesis (IBVF), Consejo Superior de Investigaciones Científicas (CSIC) and University of Seville, 41092 Seville, Spain

Rice () stands among the world's most important crop species. Rice is salt sensitive, and the undue accumulation of sodium ions (Na) in shoots has the strongest negative correlation with rice productivity under long-term salinity. The plasma membrane Na/H exchanger protein Salt Overly Sensitive 1 (SOS1) is the sole Na efflux transporter that has been genetically characterized to date. Here, the importance of SOS1-facilitated Na flux in the salt tolerance of rice was analyzed in a reverse-genetics approach. A loss-of-function mutant displayed exceptional salt sensitivity that was correlated with excessive Na intake and impaired Na loading into the xylem, thus indicating that SOS1 controls net root Na uptake and long-distance Na transport to shoots. The acute Na sensitivity of plants at low NaCl concentrations allowed analysis of the transcriptional response to sodicity stress without effects of the osmotic stress intrinsic to high-salinity treatments. In contrast with that in the wild type, mutant roots displayed preferential down-regulation of stress-related genes in response to salt treatment, despite the greater intensity of stress experienced by the mutant. These results suggest there is impaired stress detection or an inability to mount a comprehensive response to salinity in In summary, the plasma membrane Na/H exchanger SOS1 plays a major role in the salt tolerance of rice by controlling Na homeostasis and possibly contributing to the sensing of sodicity stress.
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http://dx.doi.org/10.1104/pp.19.00324DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6548274PMC
June 2019

Regulation of K Nutrition in Plants.

Front Plant Sci 2019 20;10:281. Epub 2019 Mar 20.

Instituto de Bioquímica Vegetal y Fotosíntesis, Consejo Superior de Investigaciones Científicas y Universidad de Sevilla, Seville, Spain.

Modern agriculture relies on mineral fertilization. Unlike other major macronutrients, potassium (K) is not incorporated into organic matter but remains as soluble ion in the cell sap contributing up to 10% of the dry organic matter. Consequently, K constitutes a chief osmoticum to drive cellular expansion and organ movements, such as stomata aperture. Moreover, K transport is critical for the control of cytoplasmic and luminal pH in endosomes, regulation of membrane potential, and enzyme activity. Not surprisingly, plants have evolved a large ensemble of K transporters with defined functions in nutrient uptake by roots, storage in vacuoles, and ion translocation between tissues and organs. This review describes critical transport proteins governing K nutrition, their regulation, and coordinated activity, and summarizes our current understanding of signaling pathways activated by K starvation.
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http://dx.doi.org/10.3389/fpls.2019.00281DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6435592PMC
March 2019

Exposure to Cold Unmasks Potential Biomarkers of Fibromyalgia Syndrome Reflecting Insufficient Sympathetic Responses to Stress.

Clin J Pain 2019 05;35(5):407-419

Department of Veterinary and Biomedical Sciences, University of Minnesota, Saint Paul, MN.

Objectives: Fibromyalgia syndrome (FMS) is a chronically painful condition whose symptoms are widely reported to be exacerbated by stress. We hypothesized that female patients with FMS differ from pain-free female controls in their sympathetic responses, a fact that may unmask important biomarkers and factors that contribute to the etiology of FMS.

Materials And Methods: In a pilot study, blood pressure (BP), skin temperature, thermogenic activity, circulating glucose, and pain sensitivity of 13 individuals with FMS and 11 controls at room temperature (24°C) were compared with that after exposure to cold (19°C).

Results: When measured at 24°C, BP, skin temperature, blood glucose, and brown adipose tissue (BAT) activity, measured using F-fluorodeoxyglucose positron-emission tomography/computed tomography, did not differ between controls and individuals with FMS. However, after cold exposure (19°C), BP and BAT activity increased in controls but not in individuals with FMS; skin temperature on the calf and arm decreased in controls more than in individiuals with FMS; and circulating glucose was lower in individiuals with FMS than in controls. Pain sensitivity did not change during the testing interval in response to cold.

Discussion: The convergence of the effect of cold on 4 relatively simple measures of thermogenic, cardiovascular, and metabolic activity, each regulated by sympathetic activity, strongly indicate that individuals with FMS have impaired sympathetic responses to stress that are observable and highly significant even when measured in extraordinarily small sample populations. If insufficient sympathetic responses to stress are linked to FMS, stress may unmask and maximize these potential clinical biomarkers of FMS and be related to its etiology.
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http://dx.doi.org/10.1097/AJP.0000000000000695DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6450706PMC
May 2019

K Efflux Antiporters 4, 5, and 6 Mediate pH and K Homeostasis in Endomembrane Compartments.

Plant Physiol 2018 12 11;178(4):1657-1678. Epub 2018 Oct 11.

MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, Gansu, China 730000

KEA4, KEA5, and KEA6 are members of the Arabidopsis () K efflux antiporter (KEA) family that share high sequence similarity but whose function remains unknown. Here, we show their gene expression pattern, subcellular localization, and physiological function in Arabidopsis. , , and had similar tissue expression patterns, and the three KEA proteins localized to the Golgi, the trans-Golgi network, and the prevacuolar compartment/multivesicular bodies, suggesting overlapping roles of these proteins in the endomembrane system. Phenotypic analyses of single, double, and triple mutants confirmed functional redundancy. The triple mutant had small rosettes, short seedlings, and was sensitive to low K availability and to the sodicity imposed by high salinity. Also, the mutant plants had a reduced luminal pH in the Golgi, trans-Golgi network, prevacuolar compartment, and vacuole, in accordance with the K/H exchange activity of KEA proteins. Genetic analysis indicated that KEA4, KEA5, and KEA6 as well as endosomal Na/Hexchanger5 (NHX5) and NHX6 acted coordinately to facilitate endosomal pH homeostasis and salt tolerance. Neither cancelling nor overexpressing the vacuolar antiporters and in the mutant background altered the salt-sensitive phenotype. The NHX1 and NHX2 proteins in the mutant background could not suppress the acidity of the endomembrane system but brought the vacuolar pH close to wild-type values. Together, these data signify that KEA4, KEA5, and KEA6 are endosomal K transporters functioning in maintaining pH and ion homeostasis in the endomembrane network.
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http://dx.doi.org/10.1104/pp.18.01053DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6288736PMC
December 2018

Supplementation in mushroom crops and its impact on yield and quality.

AMB Express 2018 Sep 18;8(1):146. Epub 2018 Sep 18.

Centro de Investigación, Experimentación y Servicios del Champiñón, Quintanar del Rey, Cuenca, Spain.

Mushroom supplementation is an agronomic process which consists of the application of nutritional amendments to the substrates employed for mushroom cultivation. Different nitrogen and carbohydrate rich supplements have been evaluated in crops with a substantial impact on mushroom yield and quality; however, there is still controversy regarding the nutritional requirements of mushrooms and the necessity for the development of new commercial additives. The addition of external nutrients increases the productivity of some low-yielding mushroom varieties, and therefore is a useful tool for the industry to introduce new commercially viable varieties. Spent mushroom compost is a waste material that could feasibly be recycled as a substrate to support a new commercially viable crop cycle when amended with supplements. On the other hand, a new line of research based on the use of mushroom growth promoting microorganisms is rising above the horizon to supplement the native microbiota, which appears to cover nutritional deficiencies. Several supplements employed for the cultivated mushrooms and their agronomic potential in terms of yield and quality are reviewed in this paper as a useful guide to evaluate the nutritional requirements of the crop and to design new formulas for commercial supplementation.
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http://dx.doi.org/10.1186/s13568-018-0678-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6143494PMC
September 2018