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We conducted a retrospective case-control study to assess the efficacy of personalized health guidance interventions on individuals with type 2 diabetes mellitus and obesity. A selection was made of individuals in regular visits to the Takagi Hospital for medical checkups between January 2017, and October 2021. Totally, 108 subjects (cases) with health guidance were divided into 2 groups: one group without pharmacotherapy for diabetes mellitus in medical institutions (nâ =â 92) and another group with pharmacotherapy (nâ =â 116). Cases were provided with personalized health guidance interventions by public health nurses for 30â min, in accordance with the Japanese clinical guidelines for the prevention of lifestyle-related diseases. Sex- and age-matched controls were chosen from individuals with diabetes mellitus without health guidance. The intervention without pharmacotherapy resulted in improvements in health indicators, including body weight, waist circumference, diastolic blood pressure, triglyceride levels, and γ-glutamyl trans-peptidase. These positive effects were not observed in the control group without health guidance. The therapeutic effects of health guidance were observed in cases where pharmacotherapy was administered. In conclusion, the implementation of individual health guidance interventions may prove to be effective for individuals with type 2 diabetes mellitus and obesity who regularly attend medical checkups.
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Gastrointestinal bleeding is one serious complication of patients undergoing hemodialysis with end-stage renal failure. The present study aimed to evaluate risks and clinical features of real-world clinical data on upper and lower gastrointestinal bleeding in patients undergoing hemodialysis during a 5-year longitudinal observation period. This study included 151 patients undergoing maintenance hemodialysis at Takagi Hospital between December 2017 and December 2022. Clinical data from December 2017 were recorded, and upper and lower gastrointestinal bleeding, mortality, prescribed medications, and bone fractures were examined during the five-year observation period. Of 151 patients, 32 (21.2%:4.2% per year) experienced bleeding, 24 had upper gastrointestinal bleeding, 7 had lower gastrointestinal bleeding, and one had an unknown origin of bleeding. Ulcers or erosions primarily cause upper gastrointestinal bleeding without Helicobacter pylori infection, whereas patients with H pylori eradication are more likely to experience bleeding caused by vascular lesions, often accompanied by underlying comorbidities. The prophylactic effects of proton pump inhibitors and histamine-2 receptor blockers were limited in hemodialysis patients, as 15 out of 24 patients with upper gastrointestinal bleeding (62.5%) were prescribed these medications. The mortality rate in patients with lower gastrointestinal bleeding (71.4%) was higher than that in those without bleeding (33.6%) (Pâ <â .05). All patients with lower gastrointestinal bleeding were prescribed nonsteroidal anti-inflammatory drugs and/or aspirin. In this study, endoscopic hemostasis was successfully achieved. The present study indicated that the incidence of gastrointestinal bleeding during hemodialysis was relatively high. Upper gastrointestinal bleeding may develop even with the prescription of proton pump inhibitors. Lower gastrointestinal bleeding was a complication in hemodialysis patients under serious pathological condition with nonsteroidal anti-inflammatory drugs and or aspirin.
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Infecciones por Helicobacter , Helicobacter pylori , Fallo Renal Crónico , Humanos , Inhibidores de la Bomba de Protones/uso terapéutico , Estudios de Seguimiento , Infecciones por Helicobacter/tratamiento farmacológico , Hemorragia Gastrointestinal/etiología , Hemorragia Gastrointestinal/inducido químicamente , Antiinflamatorios no Esteroideos/uso terapéutico , Aspirina/uso terapéutico , Fallo Renal Crónico/complicaciones , Fallo Renal Crónico/terapia , Fallo Renal Crónico/inducido químicamente , Diálisis Renal/efectos adversosRESUMEN
The aerial surfaces of quinoa (Chenopodium quinoa) and common ice plant (Mesembryanthemum crystallinum) are covered with a layer of epidermal bladder cells (EBCs), which are modified non-glandular trichomes previously considered to be key to the extreme salt and drought tolerance of these plants. Here, however, we find that EBCs of these plants play only minor roles, if any, in abiotic stress tolerance and in fact are detrimental under conditions of water deficit. We report that EBCs instead function as deterrents to a broad range of generalist arthropod herbivores, through their combined function of forming both a chemical and a physical barrier, and they also serve a protective function against a phytopathogen. Our study overturns current models that link EBCs to salt and drought tolerance and assigns new functions to these structures that might provide novel possibilities for protecting crops from arthropod pests.
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Herbivoria , Vejiga Urinaria , Cloruro de Sodio , Plantas , Mecanismos de DefensaRESUMEN
KEY MESSAGE: We identified and characterized a dominant FT allele for flowering without vernalization in Brassica rapa, while demonstrating its potential for deployment in breeding to accelerate flowering in various Brassicaceae crops. Controlling the timing of flowering is key to improving yield and quality of several agricultural crops including the Brassicas. Many Brassicaceae crops possess a conserved flowering mechanism in which FLOWERING LOCUS C (FLC) represses the transcription of flowering activators such as FLOWERING LOCUS T (FT) during vernalization. Here, we employed genetic analysis based on next-generation sequencing to identify a dominant FT allele, BraA.FT.2-C, for flowering in the absence of vernalization in the Brassica rapa cultivar 'CHOY SUM EX CHINA 3'. BraA.FT.2-C harbors two large insertions upstream of its coding region and is expressed without vernalization, despite FLC expression. We show that BraA.FT.2-C offers an opportunity to introduce flowering without vernalization requirement into winter-type brassica crops, including B. napus, which have many functional FLC paralogs. Furthermore, we demonstrated the feasibility of using B. rapa harboring BraA.FT.2-C as rootstock for grafting to induce flowering in radish (Raphanus sativus), which requires vernalization for flowering. We believe that the ability of BraA.FT.2-C to overcome repression by FLC can have significant applications in brassica crops breeding to increase yields by accelerating or delaying flowering.
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Brassica rapa , Brassica , Brassica rapa/genética , Alelos , Flores/genética , Flores/metabolismo , Fitomejoramiento , Brassica/genética , Regulación de la Expresión Génica de las PlantasRESUMEN
The present retrospective study aimed to examine the real-world data regarding time-dependent changes in the age distribution of patients with coronavirus disease 2019 (COVID-19) as well as the severity and infectivity in a regional core hospital in Japan. Patients with COVID-19 who visited the fever outpatient branch in Takagi Hospital during phase I (May 1 to December 31, 2021), and during phase II (January 1 to April 30, 2022) were evaluated. The age distribution of outpatients and the characteristics of inpatients aged > 75 years were compared between phases I and II. The age distribution of outpatients shifted from the older generation in phase I to the younger generation in phase II (p < 0.01). Disease severity might be reduced in a time-dependent manner with a decrease in the hospitalization rate (phase I: 145/368 (39.4%); phase II: 104/1496 (7.0%); p < 0.01) and mortality rate (phase I: 10/368 (2.7%); phase II: 7/1496 (0.5%); p < 0.01). The number of patients increased in phase II (374.0/month) compared to that in phase I (36.8/month). Regarding the older inpatients, the disease severity of COVID-19 and hospitalization days were reduced in phase II compared to those in phase I (p < 0.01, each). In conclusion, the present study suggests a change in the age distribution of patients with COVID-19, a decrease in toxicity, and an increase in infectivity of severe acute respiratory syndrome coronavirus 2 in a time-dependent manner.
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COVID-19 , Humanos , Distribución por Edad , Estudios Retrospectivos , Japón , Hospitales , Gravedad del PacienteRESUMEN
BACKGROUND AND OBJECTIVES: The objective of this study was to discover novel nodal autoantibodies in chronic inflammatory demyelinating polyneuropathy (CIDP). METHODS: We screened for autoantibodies that bind to mouse sciatic nerves and dorsal root ganglia (DRG) using indirect immunofluorescence (IFA) assays with sera from 113 patients with CIDP seronegative for anti-neurofascin 155 and anticontactin-1 antibodies and 127 controls. Western blotting, IFA assays using HEK293T cells transfected with relevant antigen expression plasmids, and cell-based RNA interference assays were used to identify target antigens. Krox20 and Periaxin expression, both of which independently control peripheral nerve myelination, was assessed by quantitative real-time PCR after application of patient and control sera to Schwann cells. RESULTS: Sera from 4 patients with CIDP, but not control sera, selectively bound to the nodal regions of sciatic nerves and DRG satellite glia (p = 0.048). The main immunoglobulin G (IgG) subtype was IgG4. IgG from these 4 patients stained a 60-kDa band on Western blots of mouse DRG and sciatic nerve lysates. These features indicated leucine-rich repeat LGI family member 4 (LGI4) as a candidate antigen. A commercial anti-LGI4 antibody and IgG from all 4 seropositive patients with CIDP showed the same immunostaining patterns of DRG and cultured rat Schwann cells and bound to the 60-kDa protein in Western blots of LGI4 overexpression lysates. IgG from 3 seropositive patients, but none from controls, bound to cells cotransfected with plasmids containing LGI4 and a disintegrin and metalloprotease domain-containing protein 22 (ADAM22), an LGI4 receptor. In cultured rat Schwann and human melanoma cells constitutively expressing LGI4, LGI4 siRNA effectively downregulated LGI4 and reduced patients' IgG binding compared with scrambled siRNA. Application of serum from a positive patient to Schwann cells expressing ADAM22 significantly reduced the expression of Krox20, but not Periaxin. Anti-LGI4 antibody-positive patients had a relatively old age at onset (mean age 58 years), motor weakness, deep and superficial sensory impairment with Romberg sign, and extremely high levels of CSF protein. Three patients showed subacute CIDP onset resembling Guillain-Barré syndrome. DISCUSSION: IgG4 anti-LGI4 antibodies are found in some elderly patients with CIDP who present subacute sensory impairment and motor weakness and are worth measuring, particularly in patients with symptoms resembling Guillain-Barré syndrome.
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Autoanticuerpos , Síndrome de Guillain-Barré , Polirradiculoneuropatía Crónica Inflamatoria Desmielinizante , Anciano , Animales , Humanos , Ratones , Persona de Mediana Edad , Ratas , Proteínas ADAM , Autoanticuerpos/sangre , Autoanticuerpos/química , Síndrome de Guillain-Barré/diagnóstico , Células HEK293 , Inmunoglobulina G , Polirradiculoneuropatía Crónica Inflamatoria Desmielinizante/inmunología , Polirradiculoneuropatía Crónica Inflamatoria Desmielinizante/patologíaRESUMEN
Betalain pigments are mainly produced by plants belonging to the order of Caryophyllales. Betalains exhibit strong antioxidant activity and responds to environmental stimuli and stress in plants. Recent reports of antioxidant, anti-inflammatory and anti-cancer properties of betalain pigments have piqued interest in understanding their biological functions. We investigated the effects of betalain pigments (betanin and isobetanin) derived from red-beet on amyloid-ß (Aß) aggregation, which causes Alzheimer's disease. Non-specific inhibition of Aß aggregation against Aß40 and Aß42 by red-beet betalain pigments, in vitro was demonstrated using the thioflavin t fluorescence assay, circular dichroism spectroscopy analysis, transmission electron microscopy and nuclear magnetic resonance (NMR) analysis. Furthermore, we examined the ability of red-beet betalain pigments to interfere with Aß toxicity by using the transgenic Caenorhabditis elegans model, which expresses the human Aß42 protein intracellularly within the body wall muscle. It responds to Aß-toxicity with paralysis and treatment with 50 µM red-beet betalain pigments significantly delayed the paralysis of C. elegans. These results suggest that betalain pigments reduce Aß-induced toxicity.
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Beta vulgaris , Betalaínas , Péptidos beta-Amiloides/química , Péptidos beta-Amiloides/metabolismo , Péptidos beta-Amiloides/toxicidad , Animales , Antioxidantes/farmacología , Beta vulgaris/química , Betalaínas/análisis , Betalaínas/química , Betalaínas/farmacología , Caenorhabditis elegans/metabolismo , Parálisis/inducido químicamenteRESUMEN
Advances in next generation sequencing (NGS)-based methodologies have accelerated the identifications of simple genetic variants such as point mutations and small insertions/deletions (InDels). Structural variants (SVs) including large InDels and rearrangements provide vital sources of genetic diversity for plant breeding. However, their analysis remains a challenge due to their complex nature. Consequently, novel NGS-based approaches are needed to rapidly and accurately identify SVs. Here, we present an NGS-based bulked-segregant analysis (BSA) technique called Sat-BSA (SVs associated with traits) for identifying SVs controlling traits of interest in crops. Sat-BSA targets allele frequencies at all SNP positions to first identify candidate genomic regions associated with a trait, which is then reconstructed by long reads-based local de novo assembly. Finally, the association between SVs, RNA-seq-based gene expression patterns and trait is evaluated for multiple cultivars to narrow down the candidate genes. We applied Sat-BSA to segregating F2 progeny obtained from crosses between turnip cultivars with different tuber colors and successfully isolated two genes harboring SVs that are responsible for tuber phenotypes. The current study demonstrates the utility of Sat-BSA for the identification of SVs associated with traits of interest in species with large and heterozygous genomes.
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Fungal plant pathogens secrete virulence-related proteins, called effectors, to establish host infection; however, the details are not fully understood yet. Functional screening of effector candidates using Agrobacterium-mediated transient expression assay in Nicotiana benthamiana identified two virulence-related effectors, named SIB1 and SIB2 (Suppression of Immunity in N. benthamiana), of an anthracnose fungus Colletotrichum orbiculare, which infects both cucurbits and N. benthamiana. The Agrobacterium-mediated transient expression of SIB1 or SIB2 increased the susceptibility of N. benthamiana to C. orbiculare, which suggested these effectors can suppress immune responses in N. benthamiana. The presence of SIB1 and SIB2 homologs was found to be limited to the genus Colletotrichum. SIB1 suppressed both (i) the generation of reactive oxygen species triggered by two different pathogen-associated molecular patterns, chitin and flg22, and (ii) the cell death response triggered by the Phytophthora infestans INF1 elicitin in N. benthamiana. We determined the NMR-based structure of SIB1 to obtain its structural insights. The three-dimensional structure of SIB1 comprises five ß-strands, each containing three disulfide bonds. The overall conformation was found to be a cylindrical shape, such as the well-known antiparallel ß-barrel structure. However, the ß-strands were found to display a unique topology, one pair of these ß-strands formed a parallel ß-sheet. These results suggest that the effector SIB1 present in Colletotrichum fungi has unique structural features and can suppress pathogen-associated molecular pattern-triggered immunity in N. benthamiana.
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Colletotrichum/metabolismo , Proteínas Fúngicas/fisiología , Inmunidad de la Planta/fisiología , Agrobacterium/patogenicidad , Secuencia de Aminoácidos , Colletotrichum/patogenicidad , Proteínas Fúngicas/química , Interacciones Huésped-Patógeno , Conformación Proteica , Especies Reactivas de Oxígeno/metabolismo , Homología de Secuencia de Aminoácido , Nicotiana/metabolismo , Nicotiana/microbiología , VirulenciaRESUMEN
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes coronavirus disease 2019 (COVID-19), has the characteristic accessory protein ORF8. Although clinical reports indicate that ORF8 variant strains (Δ382 and L84S variants) are less likely to cause severe illness, functional differences between wild-type and variant ORF8 are unknown. Furthermore, the physicochemical properties of the ORF8 protein have not been analyzed. In this study, the physicochemical properties of the wild-type ORF8 and its L84S variant were analyzed and compared. Using the tobacco BY-2 cell production system, which has been successfully used to produce the wild-type ORF8 protein with a single conformation, was used to successfully produce the ORF8 L84S variant protein at the same level as wild-type ORF8. The produced proteins were purified, and their temperature and pH dependencies were examined using nuclear magnetic resonance spectra. Our data suggested that the wild-type and L84S variant ORF8 structures are highly stable over a wide temperature range. Both proteins displayed an aggregated conformation at higher temperature that reverted when the temperature was decreased to room temperature. Moreover, ORF8 precipitated at acidic pH and this precipitation was reversed when the solution pH was shifted to neutral. Interestingly, the L84S variant exhibited greater solubility than wild-type ORF8 under acidic conditions. Thus, the finding indicated that conformational stability and reversibility of ORF8 are key properties related to function in oppressive environments.
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COVID-19/virología , SARS-CoV-2/química , Proteínas Virales/química , COVID-19/metabolismo , COVID-19/patología , Humanos , Conformación Molecular , Mutación , Resonancia Magnética Nuclear Biomolecular/métodos , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación , SARS-CoV-2/aislamiento & purificación , SARS-CoV-2/metabolismo , Relación Estructura-Actividad , Proteínas Virales/genética , Proteínas Virales/metabolismoRESUMEN
A model legume, Medicago truncatula, has over 600 nodule-specific cysteine-rich (NCR) peptides required for symbiosis with rhizobia. Among them, NCR169, an essential factor for establishing symbiosis, has four cysteine residues that are indispensable for its function. However, knowledge of NCR169 structure and mechanism of action is still lacking. In this study, we solved two NMR structures of NCR169 caused by different disulfide linkage patterns. We show that both structures have a consensus C-terminal ß-sheet attached to an extended N-terminal region with dissimilar features; one moves widely, whereas the other is relatively stapled. We further revealed that the disulfide bonds of NCR169 contribute to its structural stability and solubility. Regarding the function, one of the NCR169 oxidized forms could bind to negatively charged bacterial phospholipids. Furthermore, the positively charged lysine-rich region of NCR169 may be responsible for its antimicrobial activity against Escherichia coli and Sinorhizobium meliloti. This active region was disordered even in the phospholipid bound state, suggesting that the disordered conformation of this region is key to its function. Morphological observations suggested the mechanism of action of NCR169 on bacteria. The present study on NCR169 provides new insights into the structure and function of NCR peptides.
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Antiinfecciosos/farmacología , Péptidos Catiónicos Antimicrobianos/farmacología , Medicago truncatula/inmunología , Proteínas de Plantas/farmacología , Antiinfecciosos/inmunología , Antiinfecciosos/aislamiento & purificación , Antiinfecciosos/metabolismo , Péptidos Catiónicos Antimicrobianos/inmunología , Péptidos Catiónicos Antimicrobianos/aislamiento & purificación , Péptidos Catiónicos Antimicrobianos/metabolismo , Escherichia coli/efectos de los fármacos , Medicago truncatula/metabolismo , Medicago truncatula/microbiología , Pruebas de Sensibilidad Microbiana , Proteínas de Plantas/inmunología , Proteínas de Plantas/aislamiento & purificación , Proteínas de Plantas/metabolismo , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacología , Rizosfera , Sinorhizobium meliloti/efectos de los fármacosRESUMEN
KEY MESSAGE: Production of ORF8 protein from SARS-CoV-2 in tobacco BY-2 cells.
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COVID-19/virología , Nicotiana/metabolismo , SARS-CoV-2/genética , Proteínas Virales/metabolismo , Células Cultivadas , Humanos , Nicotiana/genética , Proteínas Virales/genéticaRESUMEN
Halophytes are plants that grow in high-salt environments and form characteristic epidermal bladder cells (EBCs) that are important for saline tolerance. To date, however, little has been revealed about the formation of these structures. To determine the genetic basis for their formation, we applied ethylmethanesulfonate mutagenesis and obtained two mutants with reduced levels of EBCs (rebc) and abnormal chloroplasts. In silico subtraction experiments revealed that the rebc phenotype was caused by mutation of REBC, which encodes a WD40 protein that localizes to the nucleus and chloroplasts. Phylogenetic and transformant analyses revealed that the REBC protein differs from TTG1, a WD40 protein involved in trichome formation. Furthermore, rebc mutants displayed damage to their shoot apices under abiotic stress, suggesting that EBCs may protect the shoot apex from such stress. These findings will help clarify the mechanisms underlying EBC formation and function.
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Chenopodium quinoa/genética , Tolerancia a la Sal/genética , Plantas Tolerantes a la Sal/genética , Repeticiones WD40/genética , Chenopodium quinoa/crecimiento & desarrollo , Chenopodium quinoa/metabolismo , Cloroplastos/genética , Células Epidérmicas/metabolismo , Regulación de la Expresión Génica de las Plantas/genética , Filogenia , Hojas de la Planta/genética , Hojas de la Planta/crecimiento & desarrollo , Salinidad , Plantas Tolerantes a la Sal/crecimiento & desarrollo , Plantas Tolerantes a la Sal/metabolismo , Estrés Fisiológico/genéticaRESUMEN
Crop plants accumulate a large amount of storage starch and storage proteins in the endosperm. Genes involved in the biosynthesis of these substances work in concert during development of the rice endosperm. The rice flo2 mutant produces aberrant seeds with reduced grain quality. FLOURRY ENDOSPERM 2 (FLO2), the causative gene of the flo2 mutant, is considered to be a regulatory protein that controls the biosynthesis of seed storage substances. FLO2 contains tetratricopeptide repeat (TPR) motifs that may mediate protein-protein interactions. In this study, we identified the protein that interacts with the TPR motif of FLO2. We generated a transformant that produced the FLAG-tagged fusion FLO2 protein in the flo2 mutant and used this in the shotgun proteomic analysis. A protein, which we named FLOC1, interacted with FLO2. In vitro pull-down assays indicated that the TPR motif was involved in this interaction. A knock-down transformant of FLOC1 showed significantly reducted fertility and generation of seeds with abnormal features. These findings suggest that FLOC1 is involved not only in seed fertility but also in seed quality. These phenotypes were also observed on the RNAi transformants of the flo2 mutant although the effect of the flo2 mutation remained. these findings imply that there is a difference in the functions of FLO2 and FLOC1 although both of appear to be involved in the control of seed quality during seed formation.
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The toxic conformer of amyloid ß-protein (Aß) ending at 42 (Aß42), which contains a unique turn conformation at amino acid residue positions 22 and 23 and tends to form oligomers that are neurotoxic, was reported to play a critical role in the pathomechanisms of Alzheimer's disease (AD), in which diabetes mellitus (DM)-like mechanisms are also suggested to be operative. It remains to be established whether the attenuation of insulin signaling is involved in an increase of toxic Aß42 conformer levels. The present study investigated the association between impaired insulin metabolism and formation of toxic Aß42 conformers in the brains of an AD mouse model. In particular, we studied whether insulin deficiency or resistance affected the formation of toxic Aß42 conformers in vivo. We induced insulin deficiency and resistance in 3xTg-AD mice, a mouse AD model harboring two familial AD-mutant APP (KM670/671NL) and PS1 (M146 V) genes and a mutant TAU (P301L) gene, by streptozotocin (STZ) injection and a high fructose diet (HFuD), respectively. Cognitive impairment was significantly worsened by STZ injection but not by HFuD. Dot blot analysis revealed significant increases in total Aß42 levels and the ratio of toxic Aß42 conformer/total Aß42 in STZ-treated mice compared with control and HFuD-fed mice. Immunostaining showed the accumulation of toxic Aß42 conformers and hyper-phosphorylated tau protein (p-tau), which was more prominent in the cortical and hippocampal neurons of STZ-treated mice compared with HFuD-fed and control mice. HFuD-fed mice showed only a mild-to-moderate increase of these proteins compared with controls. Toxic Aß42 conformers were co-localized with p-tau oligomers (Pearson's correlation coefficient = 0.62) in the hippocampus, indicating their co-aggregation. Toxic Aß42 conformer levels were inversely correlated with pancreatic insulin secretion capacity as shown by fasting immunoreactive insulin levels in STZ-treated mice (correlation coefficient = -0.5879, p = .04441), but not HFuD-fed mice, suggesting a decrease in serum insulin levels correlates with toxic Aß42 conformer formation. Levels of p-Akt and phosphorylated glycogen synthase kinase-3ß measured by a homogeneous time-resolved fluorescence assay were significantly lower in STZ-treated mice than in HFuD-fed mice, suggesting a greater inhibition of brain insulin signaling by STZ than HFuD, although both levels were significantly decreased in these groups compared with controls. Iba1-positive and NOS2-positive areas in the cortex and hippocampus were significantly increased in STZ-treated mice and to a lesser extent in HFuD-fed mice compared with controls. These findings suggest that insulin deficiency rather than insulin resistance and the resultant impairment of brain insulin signaling facilitates the formation of toxic Aß42 conformer and its co-aggregation with p-tau oligomers, and that insulin deficiency is an important pathogenic factor in the progression of AD.
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Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Disfunción Cognitiva/metabolismo , Proteínas tau/metabolismo , Enfermedad de Alzheimer/genética , Animales , Encéfalo/metabolismo , Disfunción Cognitiva/genética , Modelos Animales de Enfermedad , Insulina/metabolismo , Ratones Transgénicos , Neuronas/metabolismo , Fragmentos de Péptidos/metabolismoRESUMEN
KEY MESSAGE: An improved protocol of QTL-seq, an NGS-based method for bulked segregant analysis we previously developed in rice, allowed successful mapping of QTLs of interest in the highly heterozygous genome of B. rapa, demonstrating the power of this elegant method for genetic analyses in heterozygous species of economic importance. Recent advances in next-generation sequencing (NGS) and the various NGS-based methods developed for rapidly identifying candidate genes of interest have accelerated genetic analysis mainly in the model plants rice and Arabidopsis. Brassica rapa includes several economically important crops such as Chinese cabbage, turnip and various leafy vegetables. The application of NGS-based approaches for the analysis of B. rapa has been limited mainly due to its highly heterozygous genome and poor quality of the reference genome sequence currently available for this species. In this study, we have improved QTL-seq, a method for NGS-based bulked segregant analysis we previously developed in rice, extending its applicability for accelerating the genetic analysis and molecular breeding of B. rapa. Addition of new filters to the original QTL-seq pipeline allowed removal of spurious single-nucleotide polymorphisms caused by alignment/sequencing errors and variability between parents, significantly improving accuracy of the analysis. As proof of principle, we successfully applied the new approach to identify candidate genomic regions controlling flowering and trichome formation using segregating F2 progeny obtained from crosses made between cultivars of B. rapa showing contrasting phenotypes for these traits. We strongly believe that the improved QTL-seq method reported here will extend the applicability of NGS-based genetic analysis not only to B. rapa but also to other plant species of economic importance with heterozygous genomes.
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Brassica rapa/genética , Mapeo Cromosómico/métodos , Segregación Cromosómica , Marcadores Genéticos , Genómica/métodos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Sitios de Carácter Cuantitativo , Brassica rapa/clasificación , Cromosomas de las Plantas , Ligamiento Genético , Fenotipo , Polimorfismo de Nucleótido SimpleRESUMEN
Nuclear magnetic resonance (NMR) data directly indicated a Ca2+-dependent interaction between calmodulin (CaM) and CoDN3, a small effector of the plant pathogenic fungus Colletotrichum orbiculare, which is the causal agent of cucumber anthracnose. The overall conformation of CoDN3 is intrinsically disordered, and the CaM-binding site spans residues 34-53 of its C-terminal region. Experiments employing a chemically synthesized peptide corresponding to the CaM-binding site indicated that the CaM-binding region of CoDN3 in the Ca2+-bound CaM complex takes an α-helical conformation. Cell death suppression assay using a CoDN3 mutant lacking the CaM-binding ability suggested that the wild type CaM-binding site is necessary for full CoDN3 function in vivo.
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Calmodulina/metabolismo , Colletotrichum/metabolismo , Proteínas Fúngicas/metabolismo , Secuencia de Aminoácidos , Proteínas Fúngicas/química , Mutación/genética , Unión Proteica , Espectroscopía de Protones por Resonancia MagnéticaRESUMEN
Betalains are plant pigments primarily produced by plants of the order Caryophyllales. Because betalain possesses anti-inflammatory and anticancer activities, it may be useful as a pharmaceutical agent and dietary supplement. Recent studies have identified the genes involved in the betalain biosynthesis of betanin. Amaranthin and celosianin II are abundant in the quinoa (Chenopodium quinoa Willd.) hypocotyl, and amaranthin comprises glucuronic acid bound to betanin; therefore, this suggests the existence of a glucuronyltransferase involved in the synthesis of amaranthin in the quinoa hypocotyl. To identify the gene involved in amaranthin biosynthesis, we performed a BLAST analysis and phylogenetic tree analysis based on sequences homologous to flavonoid glycosyltransferase, followed by expression analysis on the quinoa hypocotyl to obtain three candidate proteins. Production of amaranthin in a transient Nicotiana benthamiana expression system was evaluated for these candidates and one was identified as having the ability to produce amaranthin. The gene encoding this protein was quinoa amaranthin synthetase 1 (CqAmaSy1). We also created a transgenic tobacco bright yellow-2 (BY-2) cell line wherein four betalain biosynthesis genes were introduced to facilitate amaranthin production. This transgenic cell line produced 13.67 ± 4.13 µm (mean ± SEM) amaranthin and 26.60 ± 1.53 µm betanin, whereas the production of isoamaranthin and isobetanin could not be detected. Tests confirmed the ability of amaranthin and betanin to slightly suppress cancer cell viability. Furthermore, amaranthin was shown to significantly inhibit HIV-1 protease activity, whereas betanin did not.
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Betacianinas/biosíntesis , Chenopodium quinoa/enzimología , Ligasas/aislamiento & purificación , Nicotiana/metabolismo , Proteínas de Plantas/aislamiento & purificación , Betacianinas/metabolismo , Reactores Biológicos , Células Cultivadas , Chenopodium quinoa/metabolismo , Clonación Molecular , Proteasa del VIH , Inhibidores de la Proteasa del VIH/metabolismo , Inhibidores de la Proteasa del VIH/farmacología , Ligasas/metabolismo , Redes y Vías Metabólicas , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Nicotiana/citología , Nicotiana/enzimologíaRESUMEN
Dihydrosphingosine C4 hydroxylase (DSH), a diiron-binding membrane enzyme, catalyzes the hydration of dihydrosphingosine and acyl-sphinganine to produce phytosphingosine and phytoceramide, respectively. Rice has two types of DSH homologs: general DSHs, namely DSH1, DSH2 and DSH4, and others that show spatial expression profiles, namely DSH3 and DSH5. The general DSHs exist in many plant species. These DSHs showed similarity in their functions and complemented the yeast sur2D mutation. In contrast, homologs of DSH3 and DSH5 were found only in monocot plants. Phylogenetic analysis placed these DSHs in different clades that are evolutionarily divergent from those of the general DSHs. DSH3 and DSH5 showed low-level expression. DSH5 expression was specifically in vascular bundle tissues. Ectopic expression of DSH5 induced a dwarf phenotype characterized by severe growth inhibition and an increase in the thickness of the leaf body caused by enlargement of bulliform cells in the leaves. However, no significant difference was observed in the amount of sphingolipid species. DSH5 did not complement the yeast sur2D mutation, implying that DSH5 has little effect on sphingolipid metabolism. These findings suggested that DSH3 and DSH5 originated and diverged in monocot plants.
Asunto(s)
Oxigenasas de Función Mixta/genética , Oryza/genética , Proteínas de Plantas/genética , Proteínas de Saccharomyces cerevisiae/genética , Evolución Molecular , Oxigenasas de Función Mixta/metabolismo , Familia de Multigenes , Mutación , Oryza/enzimología , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Proteínas de Plantas/metabolismo , Saccharomyces cerevisiae/enzimología , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , TransgenesRESUMEN
In quinoa seedlings, the pigment betalain accumulates in the hypocotyl. To isolate the genes involved in betalain biosynthesis in the hypocotyl, we performed ethyl methanesulfonate (EMS) mutagenesis on the CQ127 variety of quinoa seedlings. While putative amaranthin and celosianin II primarily accumulate in the hypocotyls, this process produced a green hypocotyl mutant (ghy). This MutMap+ method using the quinoa draft genome revealed that the causative gene of the mutant is CqCYP76AD1-1. Our results indicated that the expression of CqCYP76AD1-1 was light-dependent. In addition, the transient expression of CqCYP76AD1-1 in Nicotiana benthamiana leaves resulted in the accumulation of betanin but not isobetanin, and the presence of a polymorphism in CqCYP76A1-2 in the CQ127 variety was shown to have resulted in its loss of function. These findings suggested that CqCYP76AD1-1 is involved in betalain biosynthesis during the hypocotyl pigmentation process in quinoa. To our knowledge, CqCYP76AD1-1 is the first quinoa gene identified by EMS mutagenesis using a draft gene sequence.