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1.
Proc Natl Acad Sci U S A ; 121(27): e2320727121, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38923989

RESUMEN

Asthma is a widespread airway disorder where GATA3-dependent Type-2 helper T (Th2) cells and group 2 innate lymphoid cells (ILC2s) play vital roles. Asthma-associated single nucleotide polymorphisms (SNPs) are enriched in a region located 926-970 kb downstream from GATA3 in the 10p14 (hG900). However, it is unknown how hG900 affects the pathogenesis of allergic airway inflammation. To investigate the roles of the asthma-associated GATA3 enhancer region in experimental allergic airway inflammation, we first examined the correlation between GATA3 expression and the activation of the hG900 region was analyzed by flow cytometry and ChIP-qPCR. We found that The activation of enhancers in the hG900 region was strongly correlated to the levels of GATA3 in human peripheral T cell subsets. We next generated mice lacking the mG900 region (mG900KO mice) were generated by the CRISPR-Cas9 system, and the development and function of helper T cells and ILCs in mG900KO mice were analyzed in steady-state conditions and allergic airway inflammation induced by papain or house dust mite (HDM). The deletion of the mG900 did not affect the development of lymphocytes in steady-state conditions or allergic airway inflammation induced by papain. However, mG900KO mice exhibited reduced allergic inflammation and Th2 differentiation in the HDM-induced allergic airway inflammation. The analysis of the chromatin conformation around Gata3 by circular chromosome conformation capture coupled to high-throughput sequencing (4C-seq) revealed that the mG900 region interacted with the transcription start site of Gata3 with an influencing chromatin conformation in Th2 cells. These findings indicate that the mG900 region plays a pivotal role in Th2 differentiation and thus enhances allergic airway inflammation.


Asunto(s)
Asma , Diferenciación Celular , Elementos de Facilitación Genéticos , Factor de Transcripción GATA3 , Células Th2 , Factor de Transcripción GATA3/metabolismo , Factor de Transcripción GATA3/genética , Animales , Células Th2/inmunología , Ratones , Diferenciación Celular/inmunología , Asma/inmunología , Asma/genética , Asma/patología , Humanos , Ratones Noqueados , Inflamación/inmunología , Inflamación/genética , Hipersensibilidad/inmunología , Hipersensibilidad/genética , Polimorfismo de Nucleótido Simple , Ratones Endogámicos C57BL
2.
Plant Cell Physiol ; 64(11): 1301-1310, 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-36943732

RESUMEN

The quantification of stomatal pore size has long been a fundamental approach to understand the physiological response of plants in the context of environmental adaptation. Automation of such methodologies not only alleviates human labor and bias but also realizes new experimental research methods through massive analysis. Here, we present an image analysis pipeline that automatically quantifies stomatal aperture of Arabidopsis thaliana leaves from bright-field microscopy images containing mesophyll tissue as noisy backgrounds. By combining a You Only Look Once X-based stomatal detection submodule and a U-Net-based pore segmentation submodule, we achieved a mean average precision with an intersection of union (IoU) threshold of 50% value of 0.875 (stomata detection performance) and an IoU of 0.745 (pore segmentation performance) against images of leaf discs taken with a bright-field microscope. Moreover, we designed a portable imaging device that allows easy acquisition of stomatal images from detached/undetached intact leaves on-site. We demonstrated that this device in combination with fine-tuned models of the pipeline we generated here provides robust measurements that can substitute for manual measurement of stomatal responses against pathogen inoculation. Utilization of our hardware and pipeline for automated stomatal aperture measurements is expected to accelerate research on stomatal biology of model dicots.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Humanos , Arabidopsis/fisiología , Estomas de Plantas/fisiología , Hojas de la Planta/fisiología , Microscopía
3.
BMC Plant Biol ; 23(1): 391, 2023 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-37568098

RESUMEN

BACKGROUND: Plant genome information is fundamental to plant research and development. Along with the increase in the number of published plant genomes, there is a need for an efficient system to retrieve various kinds of genome-related information from many plant species across plant kingdoms. Various plant databases have been developed, but no public database covers both genomic and genetic resources over a wide range of plant species. MAIN BODY: We have developed a plant genome portal site, Plant GARDEN (Genome And Resource Database Entry: https://plantgarden.jp/en/index ), to provide diverse information related to plant genomics and genetics in divergent plant species. Elasticsearch is used as a search engine, and cross-keyword search across species is available. Web-based user interfaces (WUI) for PCs and tablet computers were independently developed to make data searches more convenient. Several types of data are stored in Plant GARDEN: reference genomes, gene sequences, PCR-based DNA markers, trait-linked DNA markers identified in genetic studies, SNPs, and in/dels on publicly available sequence read archives (SRAs). The data registered in Plant GARDEN as of March 2023 included 304 assembled genome sequences, 11,331,614 gene sequences, 419,132 DNA markers, 8,225 QTLs, and 5,934 SNP lists (gvcf files). In addition, we have re-annotated all the genes registered in Plant GARDEN by using a functional annotation tool, Hayai-Annotation, to compare the orthologous relationships among genes. CONCLUSION: The aim of Plant GARDEN is to provide plant genome information for use in the fields of plant science as well as for plant-based industries, education, and other relevant areas. Therefore, we have designed a WUI that allows a diverse range of users to access such information in an easy-to-understand manner. Plant GARDEN will eventually include a wide range of plant species for which genome sequences are assembled, and thus the number of plant species in the database will continue to expand. We anticipate that Plant GARDEN will promote the understanding of genomes and gene diversity by facilitating comparisons of the registered sequences.


Asunto(s)
Bases de Datos Genéticas , Genómica , Marcadores Genéticos , Genoma de Planta/genética , Sitios de Carácter Cuantitativo
4.
Allergol Int ; 72(2): 194-200, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36585333

RESUMEN

Asthma is characterized by increased airway hyperresponsiveness, reversible airflow limitation, and remodeling due to allergic airway inflammation. Asthma has been proposed to be classified into various phenotypes by cluster analyses integrating clinical information and laboratory data. Recently, asthma has been classified into two major endotypes, Type 2-high and Type 2-low asthma, and various subtypes based on the underlying molecular mechanisms. In Type 2-high asthma, Th2 cells, together with group 2 innate lymphoid cells (ILC2s), produce type 2 cytokines such as IL-4, IL-5, IL-9, and IL-13, which play crucial roles in causing airway inflammation. The roles of ILC2s in asthma pathogenesis have been analyzed primarily in murine models, demonstrating their importance not only in IL-33- or papain-induced innate asthma models but also in house dust mite (HDM)- or ovalbumin (OVA)-induced acquired asthma models evoked in an antigen-specific manner. Recently, evidence regarding the roles of ILC2s in human asthma is also accumulating. This minireview summarizes the roles of ILC2s in asthma, emphasizing human studies.


Asunto(s)
Asma , Inmunidad Innata , Humanos , Ratones , Animales , Linfocitos , Asma/patología , Pulmón/patología , Citocinas , Inflamación/patología , Modelos Animales de Enfermedad , Células Th2/patología
5.
Biol Cell ; 113(5): 264-269, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33443774

RESUMEN

BACKGROUND INFORMATION: Plants use transporters polarly localised in the plasma membrane for the directional transport of nutrients. The boric acid/borate (B) exporter BOR1 is localised polarly in the inner lateral domain of the plasma membrane in various root cells for efficient translocation of B under B limitation. With a high B supply, BOR1 is ubiquitinated and transported to vacuoles for degradation. The polar localisation and vacuolar targeting of BOR1 are maintained by different endocytosis mechanisms. RESULTS: We demonstrated that one of the most utilised inhibitors in endosomal recycling, brefeldin A (BFA), inhibits the polar localisation of BOR1. BFA inhibits a subset of guanine-nucleotide exchange factors (ARF-GEFs), regulators of vesicle formation. Using a transgenic line expressing BFA-resistant engineered GNOM, we identified GNOM as the key ARF-GEF in endocytosis and maintenance of the polar localisation of BOR1. CONCLUSIONS AND SIGNIFICANCE: We found that BFA inhibits the polar localisation of BOR1 by inhibiting GNOM activity. Our results suggest that GNOM-dependent endocytosis contributes to the maintenance of the polar localisation of BOR1 under B limitation. We propose a model of BOR1 transcytosis initiated from GNOM-dependent endocytosis.


Asunto(s)
Antiportadores/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Membrana Celular/metabolismo , Factores de Intercambio de Guanina Nucleótido/metabolismo , Plantas Modificadas Genéticamente/metabolismo , Brefeldino A/metabolismo , Endocitosis , Inhibidores de la Síntesis de la Proteína/metabolismo
6.
Plant J ; 102(1): 129-137, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31755157

RESUMEN

Bundle Sheath Defective 2, BSD2, is a stroma-targeted protein initially identified as a factor required for the biogenesis of ribulose 1,5-bisphosphate carboxylase/oxygenase (RuBisCO) in maize. Plants and algae universally have a homologous gene for BSD2 and its deficiency causes a RuBisCO-less phenotype. As RuBisCO can be the rate-limiting step in CO2 assimilation, the overexpression of BSD2 might improve photosynthesis and productivity through the accumulation of RuBisCO. To examine this hypothesis, we produced BSD2 overexpression lines in Arabidopsis. Compared with wild type, the BSD2 overexpression lines BSD2ox-2 and BSD2ox-3 expressed 4.8-fold and 8.8-fold higher BSD2 mRNA, respectively, whereas the empty-vector (EV) harbouring plants had a comparable expression level. The overexpression lines showed a significantly higher CO2 assimilation rate per available CO2 and productivity than EV plants. The maximum carboxylation rate per total catalytic site was accelerated in the overexpression lines, while the number of total catalytic sites and RuBisCO content were unaffected. We then isolated recombinant BSD2 (rBSD2) from E. coli and found that rBSD2 reduces disulfide bonds using reductants present in vivo, for example glutathione, and that rBSD2 has the ability to reactivate RuBisCO that has been inactivated by oxidants. Furthermore, 15% of RuBisCO freshly isolated from leaves of EV was oxidatively inactivated, as compared with 0% in BSD2-overexpression lines, suggesting that the overexpression of BSD2 maintains RuBisCO to be in the reduced active form in vivo. Our results demonstrated that the overexpression of BSD2 improves photosynthetic efficiency in Arabidopsis and we conclude that it is involved in mediating RuBisCO activation.


Asunto(s)
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Fotosíntesis/genética , Arabidopsis/crecimiento & desarrollo , Arabidopsis/metabolismo , Arabidopsis/fisiología , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/fisiología , Escherichia coli , Regulación de la Expresión Génica de las Plantas , Proteínas Recombinantes , Ribulosa-Bifosfato Carboxilasa/metabolismo
7.
Inorg Chem ; 58(10): 7062-7068, 2019 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-31070903

RESUMEN

Magnéli-phase Ti4O7, known for its high electrical conductivity and corrosion resistance, is typically prepared by hydrogen reduction at high temperatures (∼1000 °C), leading to large particles. Nanosized Ti4O7 have been explored for application toward high specific surface area electrode materials and electrocatalyst supports; nonetheless, the particle size of Ti4O7 is still insufficient for utilization as a support. In this study, we have pursued a novel synthetic approach for nanosized Ti4O7 platelets with a length of 10-80 nm and thickness of 3-10 nm even under high-temperature conditions. We herein describe the use of SiO2 beads as a core to obtain a SiO2 core coated with multilayers of TiO2 nanosheets exfoliated from layered H2Ti4O7 which is subsequently subjected to high-temperature reduction to prepare a SiO2-core@Ti4O7-shell structure. The pair distribution function technique has proven that the shell is transformed to single-phase Ti4O7. The electrical double layer capacitance of SiO2-core@Ti4O7-shell was much larger than that of conventionally synthesized Ti4O7 particles with a micrometer size. The results show the beneficial effects of the SiO2-core@Ti4O7-shell structure, and it is the first example of the synthesis for conductive Ti4O7 with a high specific surface area even under conditions of high-temperature synthesis.

8.
Proc Natl Acad Sci U S A ; 113(32): 8969-74, 2016 08 09.
Artículo en Inglés | MEDLINE | ID: mdl-27466405

RESUMEN

Domestication of crops based on artificial selection has contributed numerous beneficial traits for agriculture. Wild characteristics such as red pericarp and seed shattering were lost in both Asian (Oryza sativa) and African (Oryza glaberrima) cultivated rice species as a result of human selection on common genes. Awnedness, in contrast, is a trait that has been lost in both cultivated species due to selection on different sets of genes. In a previous report, we revealed that at least three loci regulate awn development in rice; however, the molecular mechanism underlying awnlessness remains unknown. Here we isolate and characterize a previously unidentified EPIDERMAL PATTERNING FACTOR-LIKE (EPFL) family member named REGULATOR OF AWN ELONGATION 2 (RAE2) and identify one of its requisite processing enzymes, SUBTILISIN-LIKE PROTEASE 1 (SLP1). The RAE2 precursor is specifically cleaved by SLP1 in the rice spikelet, where the mature RAE2 peptide subsequently induces awn elongation. Analysis of RAE2 sequence diversity identified a highly variable GC-rich region harboring multiple independent mutations underlying protein-length variation that disrupt the function of the RAE2 protein and condition the awnless phenotype in Asian rice. Cultivated African rice, on the other hand, retained the functional RAE2 allele despite its awnless phenotype. Our findings illuminate the molecular function of RAE2 in awn development and shed light on the independent domestication histories of Asian and African cultivated rice.


Asunto(s)
Productos Agrícolas/crecimiento & desarrollo , Oryza/crecimiento & desarrollo , Proteínas de Plantas/fisiología , Alelos , Modelos Moleculares , Oryza/genética , Proteínas de Plantas/genética
9.
Plant Cell Physiol ; 59(8): 1568-1580, 2018 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-29635388

RESUMEN

Regulation of stomatal aperture is essential for plant growth and survival in response to environmental stimuli. Opening of stomata induces uptake of CO2 for photosynthesis and transpiration, which enhances uptake of nutrients from roots. Light is the most important stimulus for stomatal opening. Under drought stress, the plant hormone ABA induces stomatal closure to prevent water loss. However, the molecular mechanisms of stomatal movements are not fully understood. In this study, we screened chemical libraries to identify compounds that affect stomatal movements in Commelina benghalensis and characterize the underlying molecular mechanisms. We identified nine stomatal closing compounds (SCL1-SCL9) that suppress light-induced stomatal opening by >50%, and two compounds (temsirolimus and CP-100356) that induce stomatal opening in the dark. Further investigations revealed that SCL1 and SCL2 had no effect on autophosphorylation of phototropin or the activity of the inward-rectifying plasma membrane (PM) K+ channel, KAT1, but suppressed blue light-induced phosphorylation of the penultimate residue, threonine, in PM H+-ATPase, which is a key enzyme for stomatal opening. SCL1 and SCL2 had no effect on ABA-dependent responses, including seed germination and expression of ABA-induced genes. These results suggest that SCL1 and SCL2 suppress light-induced stomatal opening at least in part by inhibiting blue light-induced activation of PM H+-ATPase, but not by the ABA signaling pathway. Interestingly, spraying leaves onto dicot and monocot plants with SCL1 suppressed wilting of leaves, indicating that inhibition of stomatal opening by these compounds confers tolerance to drought stress in plants.


Asunto(s)
Commelina/metabolismo , Luz , Reguladores del Crecimiento de las Plantas/farmacología , Estomas de Plantas/efectos de los fármacos , Ácido Abscísico/farmacología , Commelina/efectos de los fármacos , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , ATPasas de Translocación de Protón/metabolismo , Transducción de Señal/efectos de los fármacos
10.
New Phytol ; 218(4): 1558-1569, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29498045

RESUMEN

Floods impede gas (O2 and CO2 ) exchange between plants and the environment. A mechanism to enhance plant gas exchange under water comprises gas films on hydrophobic leaves, but the genetic regulation of this mechanism is unknown. We used a rice mutant (dripping wet leaf 7, drp7) which does not retain gas films on leaves, and its wild-type (Kinmaze), in gene discovery for this trait. Gene complementation was tested in transgenic lines. Functional properties of leaves as related to gas film retention and underwater photosynthesis were evaluated. Leaf Gas Film 1 (LGF1) was identified as the gene determining leaf gas films. LGF1 regulates C30 primary alcohol synthesis, which is necessary for abundant epicuticular wax platelets, leaf hydrophobicity and gas films on submerged leaves. This trait enhanced underwater photosynthesis 8.2-fold and contributes to submergence tolerance. Gene function was verified by a complementation test of LGF1 expressed in the drp7 mutant background, which restored C30 primary alcohol synthesis, wax platelet abundance, leaf hydrophobicity, gas film retention, and underwater photosynthesis. The discovery of LGF1 provides an opportunity to better understand variation amongst rice genotypes for gas film retention ability and to target various alleles in breeding for improved submergence tolerance for yield stability in flood-prone areas.


Asunto(s)
Adaptación Fisiológica , Inundaciones , Gases/metabolismo , Genes de Plantas , Interacciones Hidrofóbicas e Hidrofílicas , Oryza/genética , Hojas de la Planta/fisiología , Ceras/metabolismo , Secuencia de Bases , Vías Biosintéticas , Prueba de Complementación Genética , Mutación/genética , Oryza/fisiología , Fotosíntesis , Epidermis de la Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
11.
New Phytol ; 213(4): 1925-1935, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27861933

RESUMEN

Reduced seed shattering was a critical evolutionary step in crop domestication. Two cultivated rice species, Oryza sativa and Oryza glaberrima, were independently domesticated from the wild species Oryza rufipogon in Asia and Oryza barthii in Africa, respectively. A single nucleotide polymorphism (SNP) in the c gene, which encodes a trihelix transcription factor, causes nonshattering in O. sativa. However, the genetic mechanism of nonshattering in O. glaberrima is poorly understood. We conducted an association analysis for the coding sequences of SH3/SH4 in AA- genome rice species and the mutation suggested to cause nonshattering was demonstrated to do so using a positional-cloning approach in the O. sativa genetic background. We found that the loss of seed shattering in O. glaberrima was caused by an SNP resulting in a truncated SH3/SH4 protein. This mutation appears to be endemic and to have spread in the African gene pool by hybridization with some O. barthii accessions. We showed that interaction between the O. sativa and O. glaberrima domestication alleles of SH3 in heterozygotes induces a 'throwback' seed-shattering phenotype similar to that in the wild species. Identification of the causative SNP provides new insights into the molecular basis of seed shattering in crops and may facilitate investigation of the history of African rice domestication.


Asunto(s)
Domesticación , Genes de Plantas , Oryza/genética , Polimorfismo de Nucleótido Simple/genética , Selección Genética , África , Alelos , Secuencia de Bases , Ligamiento Genético , Fenotipo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Polimorfismo de Longitud del Fragmento de Restricción
12.
Plant Cell Physiol ; 57(6): 1220-30, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27048369

RESUMEN

The stomatal apparatus consists of a pair of guard cells and regulates gas exchange between the leaf and atmosphere. In guard cells, blue light (BL) activates H(+)-ATPase in the plasma membrane through the phosphorylation of its penultimate threonine, mediating stomatal opening. Although this regulation is thought to be widely adopted among kidney-shaped guard cells in dicots, the molecular basis underlying that of dumbbell-shaped guard cells in monocots remains unclear. Here, we show that H(+)-ATPases are involved in the regulation of dumbbell-shaped guard cells. Stomatal opening of rice was promoted by the H(+)-ATPase activator fusicoccin and by BL, and the latter was suppressed by the H(+)-ATPase inhibitor vanadate. Using H(+)-ATPase antibodies, we showed the presence of phosphoregulation of the penultimate threonine in Oryza sativa H(+)-ATPases (OSAs) and localization of OSAs in the plasma membrane of guard cells. Interestingly, we identified one H(+)-ATPase isoform, OSA7, that is preferentially expressed among the OSA genes in guard cells, and found that loss of function of OSA7 resulted in partial insensitivity to BL. We conclude that H(+)-ATPase is involved in BL-induced stomatal opening of dumbbell-shaped guard cells in monocotyledon species.


Asunto(s)
Forma de la Célula , Oryza/citología , Oryza/enzimología , Proteínas de Plantas/metabolismo , Estomas de Plantas/citología , ATPasas de Translocación de Protón/metabolismo , Secuencia de Aminoácidos , Forma de la Célula/efectos de la radiación , Regulación de la Expresión Génica de las Plantas/efectos de la radiación , Luz , Oryza/genética , Oryza/efectos de la radiación , Fosforilación/efectos de la radiación , Fosfotreonina/metabolismo , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Estomas de Plantas/fisiología , Estomas de Plantas/efectos de la radiación , ATPasas de Translocación de Protón/química , Plantones/metabolismo , Plantones/efectos de la radiación
13.
Plant Cell ; 25(5): 1709-25, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23715469

RESUMEN

Plasticity of root growth in response to environmental cues and stresses is a fundamental characteristic of land plants. However, the molecular basis underlying the regulation of root growth under stressful conditions is poorly understood. Here, we report that a rice nuclear factor, RICE SALT SENSITIVE3 (RSS3), regulates root cell elongation during adaptation to salinity. Loss of function of RSS3 only moderately inhibits cell elongation under normal conditions, but it provokes spontaneous root cell swelling, accompanied by severe root growth inhibition, under saline conditions. RSS3 is preferentially expressed in the root tip and forms a ternary complex with class-C basic helix-loop-helix (bHLH) transcription factors and JASMONATE ZIM-DOMAIN proteins, the latter of which are the key regulators of jasmonate (JA) signaling. The mutated protein arising from the rss3 allele fails to interact with bHLH factors, and the expression of a significant portion of JA-responsive genes is upregulated in rss3. These results, together with the known roles of JAs in root growth regulation, suggest that RSS3 modulates the expression of JA-responsive genes and plays a crucial role in a mechanism that sustains root cell elongation at appropriate rates under stressful conditions.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Ciclopentanos/farmacología , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Oxilipinas/farmacología , Proteínas de Plantas/genética , Raíces de Plantas/genética , Adaptación Fisiológica/genética , Secuencia de Aminoácidos , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Perfilación de la Expresión Génica , Microscopía Fluorescente , Datos de Secuencia Molecular , Mutación , Análisis de Secuencia por Matrices de Oligonucleótidos , Oryza/genética , Oryza/crecimiento & desarrollo , Oryza/metabolismo , Reguladores del Crecimiento de las Plantas/farmacología , Proteínas de Plantas/metabolismo , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/metabolismo , Unión Proteica , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Salinidad , Homología de Secuencia de Aminoácido , Cloruro de Sodio/farmacología , Técnicas del Sistema de Dos Híbridos
14.
Plant Cell Physiol ; 56(10): 1867-76, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26329877

RESUMEN

Environmental stress tolerance is an important trait for crop improvement. In recent decades, numerous genes that confer tolerance to abiotic stress such as salinity were reported. However, the levels of salt tolerance differ greatly depending on growth conditions, and mechanisms underlying the complicated nature of stress tolerance are far from being fully understood. In this study, we investigated the profiles of stress tolerance of nine salt-tolerant rice varieties and transgenic rice lines carrying constitutively expressed genes that are potentially involved in salt tolerance, by evaluating their growth and viability under salt, heat, ionic and hyperosmotic stress conditions. Profiling of the extant varieties and selected chromosome segment substitution lines showed that salt tolerance in a greenhouse condition was more tightly correlated with ionic stress tolerance than osmotic stresses. In Nona Bokra, one of the most salt-tolerant varieties, the contribution of the previously identified sodium transporter HKT1;5 to salt tolerance was fairly limited. In addition, Nona Bokra exhibited high tolerance to all the stresses imposed. More surprisingly, comparative evaluation of 74 stress tolerance genes revealed that the most striking effect to enhance salt tolerance was conferred by overexpressing CYP94C2b, which promotes deactivation of jasmonate. In contrast, genes encoding ABA signaling factors conferred multiple stress tolerance. Genes conferring tolerance to both heat and hyperosmotic stresses were preferentially linked to functional categories related to heat shock proteins, scavenging of reactive oxygen species and Ca(2+) signaling. These comparative profiling data provide a new basis for understanding the ability of plants to grow under harsh environmental conditions.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Oryza/genética , Proteínas de Plantas/genética , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/fisiología , Plantas Tolerantes a la Sal/genética , Ciclopentanos/farmacología , Sequías , Calor , Oryza/efectos de los fármacos , Presión Osmótica/efectos de los fármacos , Oxilipinas/farmacología , Plantas Modificadas Genéticamente/efectos de los fármacos , Plantas Tolerantes a la Sal/efectos de los fármacos , Cloruro de Sodio/farmacología
15.
Plant Cell Physiol ; 56(4): 779-89, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25637374

RESUMEN

The plant hormone jasmonate and its conjugates (JAs) have important roles in growth control, leaf senescence and defense responses against insects and microbial attacks. JA biosynthesis is induced by several stresses, including mechanical wounding, pathogen attacks, drought and salinity stresses. However, the roles of JAs under abiotic stress conditions are unclear. Here we report that increased expression of the Cyt P450 family gene CYP94C2b enhanced viability of rice plants under saline conditions. This gene encodes an enzyme closely related to CYP94C1 that catalyzes conversion of bioactive jasmonate-isoleucine (JA-Ile) into 12OH-JA-Ile and 12COOH-JA-Ile. Inactivation of JA was facilitated in a rice line with enhanced CYP94C2b expression, and responses to exogenous JA and wounding were alleviated. Moreover, salt stress-induced leaf senescence but not natural senescence was delayed in the transgenic rice. These results suggest that bioactive JAs have a negative effect on viability under salt stress conditions and demonstrate that manipulating JA metabolism confers enhanced salt tolerance in rice.


Asunto(s)
Ciclopentanos/farmacología , Sistema Enzimático del Citocromo P-450/genética , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Familia de Multigenes , Oryza/genética , Oxilipinas/farmacología , Tolerancia a la Sal/genética , Proliferación Celular/efectos de los fármacos , Sistema Enzimático del Citocromo P-450/metabolismo , Genes de Plantas , Oryza/citología , Oryza/efectos de los fármacos , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/crecimiento & desarrollo , Brotes de la Planta/efectos de los fármacos , Brotes de la Planta/genética , Salinidad , Tolerancia a la Sal/efectos de los fármacos , Cloruro de Sodio/farmacología , Estrés Fisiológico/efectos de los fármacos
16.
J Vis Exp ; (204)2024 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-38407316

RESUMEN

Stomata are microscopic pores found in the plant leaf epidermis. Regulation of stomatal aperture is pivotal not only for balancing carbon dioxide uptake for photosynthesis and transpirational water loss but also for restricting bacterial invasion. While plants close stomata upon recognition of microbes, pathogenic bacteria, such as Pseudomonas syringae pv. tomato DC3000 (Pto), reopen the closed stomata to gain access into the leaf interior. In conventional assays for assessing stomatal responses to bacterial invasion, leaf epidermal peels, leaf discs, or detached leaves are floated on bacterial suspension, and then stomata are observed under a microscope followed by manual measurement of stomatal aperture. However, these assays are cumbersome and may not reflect stomatal responses to natural bacterial invasion in a leaf attached to the plant. Recently, a portable imaging device was developed that can observe stomata by pinching a leaf without detaching it from the plant, together with a deep learning-based image analysis pipeline designed to automatically measure stomatal aperture from leaf images captured by the device. Here, building on these technical advances, a new method to assess stomatal responses to bacterial invasion in Arabidopsis thaliana is introduced. This method consists of three simple steps: spray inoculation of Pto mimicking natural infection processes, direct observation of stomata on a leaf of the Pto-inoculated plant using the portable imaging device, and automated measurement of stomatal aperture by the image analysis pipeline. This method was successfully used to demonstrate stomatal closure and reopening during Pto invasion under conditions that closely mimic the natural plant-bacteria interaction.


Asunto(s)
Arabidopsis , Solanum lycopersicum , Pseudomonas syringae , Bioensayo , Transporte Biológico
17.
RMD Open ; 10(1)2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38388170

RESUMEN

OBJECTIVES: This study aimed to determine the immunogenicity and the influence on disease activity of an adjuvanted recombinant varicella-zoster virus (VZV) subunit vaccine (RZV) in patients with rheumatoid arthritis (RA) treated with disease-modifying antirheumatic drugs (DMARDs). METHODS: This prospective longitudinal study enrolled 53 patients with RA (aged ≥50 years) treated with DMARDs (conventional synthetic (cs)DMARDs 20, biological (b)DMARDs 23 and targeted synthetic (ts)DMARDs 10) and 10 control individuals. The participants received two intramuscular RZV 2 months apart. VZV-specific CD4+ T cell responses (cell-mediated immunity; CMI) and IgG antibody responses (humoral immunity; HI) were assessed at 0 and 3 months after the first RZV administration using flow cytometry and enzyme immunoassay, respectively. Disease activity (Disease Activity Score 28-C reactive protein and Clinical Disease Activity Index), flares and adverse events were monitored for 6 months after the first vaccination. RESULTS: VZV-specific CMI and HI significantly increased in the three DMARDs-treated patients with RA after RZV administration compared with the corresponding prevaccination values (p<0.001-0.014), and the magnitudes and fold-increases of those responses were not significantly different among the three DMARDs-treated patients with RA. Furthermore, the vaccine response rates of CMI and HI were not significantly different between csDMARDs-treated patients and b-DMARDs or ts-DMARDs-treated patients. Meanwhile, no significant increases in disease activity indices or adverse events were observed in these patients during the 6-month follow-up period after the first vaccination. RZV-induced RA flares occurred in two patients (3.8%) but were mild and controllable. CONCLUSION: RZV is robustly immunogenic and has a clinically acceptable safety profile in elderly patients with RA receiving DMARDs.


Asunto(s)
Antirreumáticos , Artritis Reumatoide , Vacuna contra el Herpes Zóster , Herpes Zóster , Anciano , Humanos , Vacuna contra el Herpes Zóster/efectos adversos , Estudios Prospectivos , Estudios Longitudinales , Herpes Zóster/epidemiología , Herpes Zóster/etiología , Herpes Zóster/prevención & control , Antirreumáticos/efectos adversos , Herpesvirus Humano 3 , Vacunas Sintéticas/efectos adversos
18.
Nat Commun ; 15(1): 5610, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38969652

RESUMEN

Group 2 innate lymphoid cells (ILC2s) are a subset of innate lymphocytes that produce type 2 cytokines, including IL-4, IL-5, and IL-13. GATA3 is a critical transcription factor for ILC2 development at multiple stages. However, when and how GATA3 is induced to the levels required for ILC2 development remains unclear. Herein, we identify ILC2-specific GATA3-related tandem super-enhancers (G3SE) that induce high GATA3 in ILC2-committed precursors. G3SE-deficient mice exhibit ILC2 deficiency in the bone marrow, lung, liver, and small intestine with minimal impact on other ILC lineages or Th2 cells. Single-cell RNA-sequencing and subsequent flow cytometry analysis show that GATA3 induction mechanism, which is required for entering the ILC2 stage, is lost in IL-17RB+PD-1- late ILC2-committed precursor stage in G3SE-deficient mice. Cnot6l, part of the CCR4-NOT deadenylase complex, is a possible GATA3 target during ILC2 development. Our findings implicate a stage-specific regulatory mechanism for GATA3 expression during ILC2 development.


Asunto(s)
Linaje de la Célula , Factor de Transcripción GATA3 , Inmunidad Innata , Linfocitos , Animales , Factor de Transcripción GATA3/metabolismo , Factor de Transcripción GATA3/genética , Ratones , Linfocitos/inmunología , Linfocitos/metabolismo , Linfocitos/citología , Ratones Endogámicos C57BL , Ratones Noqueados , Elementos de Facilitación Genéticos/genética , Células Th2/inmunología , Diferenciación Celular/inmunología , Análisis de la Célula Individual
19.
Nat Commun ; 14(1): 2665, 2023 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-37188667

RESUMEN

Stomatal pores in the plant epidermis open and close to regulate gas exchange between leaves and the atmosphere. Upon light stimulation, the plasma membrane (PM) H+-ATPase is phosphorylated and activated via an intracellular signal transduction pathway in stomatal guard cells, providing a primary driving force for the opening movement. To uncover and manipulate this stomatal opening pathway, we screened a chemical library and identified benzyl isothiocyanate (BITC), a Brassicales-specific metabolite, as a potent stomatal-opening inhibitor that suppresses PM H+-ATPase phosphorylation. We further developed BITC derivatives with multiple isothiocyanate groups (multi-ITCs), which demonstrate inhibitory activity on stomatal opening up to 66 times stronger, as well as a longer duration of the effect and negligible toxicity. The multi-ITC treatment inhibits plant leaf wilting in both short (1.5 h) and long-term (24 h) periods. Our research elucidates the biological function of BITC and its use as an agrochemical that confers drought tolerance on plants by suppressing stomatal opening.


Asunto(s)
Proteínas de Arabidopsis , Estomas de Plantas , Estomas de Plantas/metabolismo , Luz , Resistencia a la Sequía , ATPasas de Translocación de Protón/metabolismo , Isotiocianatos/farmacología , Isotiocianatos/metabolismo , Proteínas de Arabidopsis/metabolismo
20.
Front Plant Sci ; 13: 949470, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36311127

RESUMEN

Wild species of lettuce (Lactuca sp.) are thought to have first been domesticated for oilseed contents to provide seed oil for human consumption. Although seed morphology is an important trait contributing to oilseed in lettuce, the underlying genetic mechanisms remain elusive. Since lettuce seeds are small, a manual phenotypic determination required for a genetic dissection of such traits is challenging. In this study, we built and applied an instance segmentation-based seed morphology quantification pipeline to measure traits in seeds generated from a cross between the domesticated oilseed type cultivar 'Oilseed' and the wild species 'UenoyamaMaruba' in an automated manner. Quantitative trait locus (QTL) mapping following ddRAD-seq revealed 11 QTLs linked to 7 seed traits (area, width, length, length-to-width ratio, eccentricity, perimeter length, and circularity). Remarkably, the three QTLs with the highest LOD scores, qLWR-3.1, qECC-3.1, and qCIR-3.1, for length-to-width ratio, eccentricity, and circularity, respectively, mapped to linkage group 3 (LG3) around 161.5 to 214.6 Mb, a region previously reported to be associated with domestication traits from wild species. These results suggest that the oilseed cultivar harbors genes acquired during domestication to control seed shape in this genomic region. This study also provides genetic evidence that domestication arose, at least in part, by selection for the oilseed type from wild species and demonstrates the effectiveness of image-based phenotyping to accelerate discoveries of the genetic basis for small morphological features such as seed size and shape.

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