RESUMEN
Lactobacillus rhamnosus GG (LGG), the well-characterized human-derived probiotic strain, possesses excellent properties in the maintenance of intestinal homeostasis, immunoregulation and defense against gastrointestinal pathogens in mammals. Here, we demonstrate that the SpaC pilin of LGG causes intestinal epithelium injury by inducing cell pyroptosis and gut microbial dysbiosis in zebrafish. Dietary SpaC activates Caspase-3-GSDMEa pathways in the intestinal epithelium, promotes intestinal pyroptosis and increases lipopolysaccharide (LPS)-producing gut microbes in zebrafish. The increased LPS subsequently activates Gaspy2-GSDMEb pyroptosis pathway. Further analysis reveals the Caspase-3-GSDMEa pyroptosis is initiated by the species-specific recognition of SpaC by TLR4ba, which accounts for the species-specificity of the SpaC-inducing intestinal pyroptosis in zebrafish. The observed pyroptosis-driven gut injury and microbial dysbiosis by LGG in zebrafish suggest that host-specific beneficial/harmful mechanisms are critical safety issues when applying probiotics derived from other host species and need more attention.
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Black shank disease caused by Phytophthora nicotianae is one of the most important diseases in tobacco worldwide and can result in a devastating loss in tobacco cultivation. Many efforts have been carried out to identify the chromosome segment from Nicotiana plumbaginifolia containing a resistance locus carrying a gene named Php; however, the Php gene has not been cloned, and knowledge of the potential mechanism of the Php gene in the resistant lines is limited. To further characterize the resistance mechanism of the Php gene, we first used the resistant line "RBST" and the susceptible cultivar "Honghuadajinyuan" (HD) to obtain the near-isogenic line RBS89 containing the Php gene from RBST. RBS89 showed high resistance to black shank disease. Transcriptomic and iTRAQ analyses were applied to explore the potential defense mechanisms in RBS89 plants in comparison with HD plants with or without inoculation. Many differentially expressed genes (DEGs) and proteins were identified, and some pathogenesis-related (PR) proteins were extensively abundant in the RBS89 plants when compared with the HD plants in response to black shank disease. Importantly, overexpression of the PR gene NtPR-1B in HD plants improved the resistance of tobacco plants to black shank disease, indicating that NtPR-1B and Php genes might have similar roles in protecting tobacco from black shank disease. However, the relationship between NtPR-1B and Php genes requires further analysis. Therefore, our study provides valuable information for breeding tobacco cultivars with black shank disease resistance and sheds light on the defense mechanism of black shank disease in tobacco for enhancing Phytophthora resistance in other Solanaceae crops.
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The bHLH transcription factors play pivotal roles in plant growth and development, production of secondary metabolites and responses to various environmental stresses. Although the bHLH genes have been well studied in model plant species, a comprehensive investigation of the bHLH genes is required for tobacco with newly obtained high-quality genome. In the present study, a total of 309 NtbHLH genes were identified and can be divided into 23 subfamilies. The conserved amino acids which are essential for their function were predicted for the NtbHLH proteins. Moreover, the NtbHLH genes were conserved during evolution through analyzing the gene structures and conserved motifs. A total of 265 NtbHLH genes were localized in the 24 tobacco chromosomes while the remained 44 NtbHLH genes were mapped to the scaffolds due to the complexity of tobacco genome. Moreover, transcripts of NtbHLH genes were obviously tissue-specific expressed from the gene-chip data from 23 tobacco tissues, and expressions of 20 random selected NtbHLH genes were further confirmed by quantitative real-time PCR, indicating their potential functions in the plant growth and development. Importantly, overexpressed NtbHLH86 gene confers improve drought tolerance in tobacco indicating that it might be involved in the regulation of drought stress. Therefore, our findings here provide a valuable information on the characterization of NtbHLH genes and further investigation of their functions in tobacco.
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MADS-box genes play a pivotal role in various processes, including floral and seed development, controlling flowering time, regulation of fruits ripening, and respond to abiotic and biotic stressors in planta. Tobacco (Nicotiana tabacum) has been widely used as a model plant for analyzing the gene function, however, there has been less information on the regulation of flowering, and the associated genes. In the present study, a total of 168 NtMADS-box genes were identified from tobacco, and their phylogenetic relationship, chromosome locations, and gene structures were further analyzed. NtMADS-box genes can be clustered into four sub-families of Mα, Mγ, MIKC*, and MIKCC. A total of 111 NtMADS-box genes were distributed on 20 chromosomes, and 57 NtMADS-box genes were located on the unanchored scaffolds due to the complex and incomplete assembly of the tobacco genome. Expression profiles of NtMADS-box genes by microarray from 23 different tissues indicated that members in different NtMADS-box gene subfamilies might play specific roles in the growth and flower development, and the transcript levels of 24 NtMADS-box genes were confirmed by quantitative real-time PCR. Importantly, overexpressed NtSOC1/NtMADS133 could promote early flowering and dwarfism in transgenic tobacco plants. Therefore, our findings provide insights on the characterization of NtMADS-box genes to further study their functions in plant development.
Asunto(s)
Perfilación de la Expresión Génica/métodos , Proteínas de Dominio MADS/genética , Nicotiana/crecimiento & desarrollo , Análisis de Secuencia de ADN/métodos , Mapeo Cromosómico , Evolución Molecular , Regulación del Desarrollo de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Familia de Multigenes , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Filogenia , Proteínas de Plantas/genética , Nicotiana/genéticaRESUMEN
The homeodomain-leucine zipper (HD-Zip) gene family, whose members play vital roles in plant growth and development, and participate in responding to various stresses, is an important class of transcription factors currently only found in plants. Although the HD-Zip gene family, especially the HD-Zip I subfamily, has been extensively studied in many plant species, the systematic report on HD-Zip I subfamily in cultivated tobacco (Nicotiana tabacum) is lacking. In this study, 39 HD-Zip I genes were systematically identified in N. tabacum (Nt). Interestingly, that 64.5% of the 31 genes with definite chromosome location information were found to originate from N. tomentosoformis, one of the two ancestral species of allotetraploid N. tabacum. Phylogenetic analysis divided the NtHD-Zip I subfamily into eight clades. Analysis of gene structures showed that NtHD-Zip I proteins contained conserved homeodomain and leucine-zipper domains. Three-dimensional structure analysis revealed that most NtHD-Zip I proteins in each clade, except for those in clade η, share a similar structure to their counterparts in Arabidopsis. Prediction of cis-regulatory elements showed that a number of elements responding to abscisic acid and different abiotic stresses, including low temperature, drought, and salinity, existed in the promoter region of NtHD-Zip I genes. The prediction of Arabidopsis ortholog-based protein-protein interaction network implied that NtHD-Zip I proteins have complex connections. The expression profile of these genes showed that different NtHD-Zip I genes were highly expressed in different tissues and could respond to abscisic acid and low-temperature treatments. Our study provides insights into the evolution and expression patterns of NtHD-Zip I genes in N. tabacum and will be useful for further functional characterization of NtHD-Zip I genes in the future.
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Proteínas de Homeodominio/genética , Nicotiana/genética , Proteínas de Plantas/genética , Factores de Transcripción/genética , Evolución Molecular , Proteínas de Homeodominio/química , Proteínas de Homeodominio/metabolismo , Leucina Zippers , Familia de Multigenes , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Estrés Fisiológico , Nicotiana/clasificación , Nicotiana/metabolismo , Factores de Transcripción/química , Factores de Transcripción/metabolismoRESUMEN
BACKGROUND: Abscisic acid (ABA) is an important phytohormone for plant growth, development and responding to stresses such as drought, salinity, and pathogen infection. Pyrabactin Resistance 1 (PYR1)/PYR1-Like (PYL)/Regulatory Component of ABA Receptor (RCAR) (hereafter referred to as PYLs) has been identified as the ABA receptors. The PYL family members have been well studied in many plants. However, the members of PYL family have not been systematically identified at genome level in cultivated tobacco (Nicotiana tabacum) and its two ancestors. In this study, the phylogenic relationships, chromosomal distribution, gene structures, conserved motifs/regions, and expression profiles of NtPYLs were analyzed. RESULTS: We identified 29, 11, 16 PYLs in the genomes of allotetraploid N. tabacum, and its two diploid ancestors N. tomentosiformis and N. sylvestris, respectively. The phylogenetic analysis revealed that NtPYLs can be divided into three subfamilies, and each NtPYL has one counterpart in N. sylvestris or N. tomentosiformis. Based on microarray analysis of NtPYL transcripts, four NtPYLs (from subfamily II, III), and five NtPYLs (from subfamily I) are highlighted as potential candidates for further functional characterization in N. tabacum seed development, response to ABA, and germination, and resistance to abiotic stresses, respectively. Interestingly, the expression profiles of members in the same NtPYL subfamily showed somehow similar patterns in tissues at different developmental stages and in leaves of seedlings under drought stress, suggesting particular NtPYLs might have multiple functions in both plant development and drought stress response. CONCLUSIONS: NtPYLs are highlighted for important functions in seed development, germination and response to ABA, and particular in drought tolerance. This work will not only shed light on the PYL family in tobacco, but also provides some valuable information for functional characterization of ABA receptors in N. tabacum.
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Ácido Abscísico/metabolismo , Sequías , Evolución Molecular , Genómica , Nicotiana/fisiología , Proteínas de Plantas/genética , Estrés Fisiológico/genética , Arabidopsis/genética , Secuencia de Bases , Cromosomas de las Plantas/genética , Secuencia Conservada/genética , Regulación de la Expresión Génica de las Plantas , Filogenia , Proteínas de Plantas/metabolismo , Glycine max/genética , Nicotiana/genética , Nicotiana/crecimiento & desarrolloRESUMEN
Drought is one of the most severe forms of abiotic stresses that threaten the survival of plants, including crops. In turn, plants dramatically change their physiology to increase drought tolerance, including reconfiguration of proteomes. Here, we studied drought-induced proteomic changes in leaves of cultivated tobacco (Nicotiana tabacum), a solanaceous plant, using the isobaric tags for relative and absolute quantitation (iTRAQ)-based protein labeling technology. Of identified 5570 proteins totally, drought treatment increased and decreased abundance of 260 and 206 proteins, respectively, compared with control condition. Most of these differentially regulated proteins are involved in photosynthesis, metabolism, and stress and defense. Although abscisic acid (ABA) levels greatly increased in drought-treated tobacco leaves, abundance of detected ABA biosynthetic enzymes showed no obvious changes. In contrast, heat shock proteins (HSPs), thioredoxins, ascorbate-, glutathione-, and hydrogen peroxide (H2O2)-related proteins were up- or down-regulated in drought-treated tobacco leaves, suggesting that chaperones and redox signaling are important for tobacco tolerance to drought, and it is likely that redox-induced posttranslational modifications play an important role in modulating protein activity. This study not only provides a comprehensive dataset on overall protein changes in drought-treated tobacco leaves, but also shed light on the mechanism by which solanaceous plants adapt to drought stress.
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Sequías , Respuesta al Choque Térmico/fisiología , Nicotiana/fisiología , Hojas de la Planta/fisiología , Proteínas de Plantas/metabolismo , Proteoma/metabolismo , Aclimatación/fisiología , Regulación de la Expresión Génica de las Plantas/fisiología , Proteínas de Choque Térmico/metabolismo , Marcaje Isotópico/métodos , Mapeo Peptídico/métodos , Proteómica/métodos , Espectrometría de Masas en Tándem/métodosRESUMEN
The plant hormone abscisic acid (ABA) plays important roles in regulating plant growth, development, and responses to environmental stresses. Proteins in the PYR/PYL/RCAR family (hereafter referred to as PYLs) are known as ABA receptors. Since most studies thus far have focused on Arabidopsis PYLs, little is known about PYL homologs in crop plants. We report here the characterization of 21 PYL homologs (GmPYLs) in soybean. Twenty-three putative GmPYLs can be found from soybean genome sequence and categorized into three subgroups. GmPYLs interact with AtABI1 and two GmPP2Cs in diverse manners. A lot of the subgroup I GmPYLs interact with PP2Cs in an ABA-dependent manner, whereas most of the subgroup II and III GmPYLs bind to PP2Cs in an ABA-independent manner. The subgroup III GmPYL23, which cannot interact with any of the tested PP2Cs, differs from other GmPYLs. The CL2/gate domain is crucial for GmPYLs-PP2Cs interaction, and a mutation in the conserved proline (P109S) abolishes the interaction between GmPYL1 and AtABI1. Furthermore, the ABA dependence of GmPYLs-PP2Cs interactions are partially correlated with two amino acid residues preceding the CL2/gate domain of GmPYLs. We also show that GmPYL1 interacts with AtABI1 in an ABA-dependent manner in plant cells. Three GmPYLs differentially inhibit AtABI1 and GmPP2C1 in an ABA-dependent or -enhanced manner in vitro. In addition, ectopically expressing GmPYL1 partially restores ABA sensitivity of the Arabidopsis triple mutant pyr1/pyl1/pyl4. Taken together, our results suggest that soybean GmPYLs are ABA receptors that function by interacting and inhibiting PP2Cs.
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Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/metabolismo , Glycine max/metabolismo , Fosfoproteínas Fosfatasas/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Proteínas de Arabidopsis/genética , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Clonación Molecular , Péptidos y Proteínas de Señalización Intracelular , Proteínas de Transporte de Membrana/genética , Proteínas de Transporte de Membrana/metabolismo , Fosfoproteínas Fosfatasas/genética , Filogenia , Proteína Fosfatasa 2C , Glycine max/genética , Técnicas del Sistema de Dos HíbridosRESUMEN
The brassinosteroid (BR) receptor, BR insensitive 1 (BRI1), plays a critical role in plant development, but whether BRI1-mediated BR signaling is involved in plant defense responses to herbivores was largely unknown. Here, we examined the function of BRI1 in the resistance of Nicotiana attenuata (Solanaceae) to its specialist insect herbivore Manduca sexta. Jasmonic acid (JA) and JA-isoleucine conjugate (JA-Ile) are important hormones that mediate resistance to herbivores and we found that after wounding or simulated herbivory NaBRI1 had little effect on JA levels, but was important for the induction of JA-Ile. Further experiments revealed that decreased JAR (the enzyme for JA-Ile production) activity and availability of Ile in NaBRI1-silenced plants were likely responsible for the low JA-Ile levels. Consistently, M. sexta larvae gained more weight on NaBRI1-silenced plants than on the control plants. Quantification of insect feeding-induced secondary metabolites revealed that silencing NaBRI1 resulted in decreased levels of carbon-rich defensive secondary metabolites (hydroxygeranyllinalool diterpene glycosides, chlorogenic acid, and rutin), but had little effect on the nitrogen-rich ones (nicotine and trypsin proteinase inhibitors). Thus, NaBRI1-mediated BR signaling is likely involved in plant defense responses to M. sexta, including maintaining JA-Ile levels and the accumulation of several carbon-rich defensive secondary metabolites.
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Ciclopentanos/metabolismo , Diterpenos/metabolismo , Glicósidos/metabolismo , Herbivoria/fisiología , Isoleucina/análogos & derivados , Oxilipinas/metabolismo , Animales , Isoleucina/metabolismo , Nicergolina/metabolismo , Proteínas de Plantas/metabolismo , Inhibidores de TripsinaRESUMEN
Calcium-dependent protein kinases (CDPKs) modulate plant development and growth and are important regulators of biotic and abiotic stress responses. Recently it was found that simultaneously silencing Nicotiana attenuata NaCDPK4 and NaCDPK5 (IRcdpk4/5 plants) results in accumulation of exceptionally high JA levels after wounding or simulated herbivory treatments, which in turn induced high levels of defense metabolites that slowed the growth of Manduca sexta, a specialist insect herbivore. To investigate the mechanism by which NaCDPK4 and NaCDPK5 regulate JA accumulation, we analyzed the transcript levels of all important enzymes involved in JA biosynthesis, but these genes showed no differences between wild-type and IRcdpk4/5 plants. Moreover, the dynamics of JA were similar between these plants, excluding the possibility of decreased degradation rates in IRcdpk4/5 plants. To gain insight into the mechanism by which NaCDPK4 and NaCDPK5 regulate JA biosynthesis, free fatty acids, including C18:3, and (9S,13S)-12-oxo-phytodienoic acid (OPDA), two important precursors of JA were quantified at different times before and after wounding and simulated herbivore feeding treatments. We show that after these treatments, IRcdpk4/5 plants have decreased levels of C18:3, but have enhanced OPDA and JA levels, suggesting that NaCDPK4 and NaCDPK5 have a role in the early steps of JA biosynthesis. The possible role of NaCDPK4 and NaCDPK5 regulating AOS and AOC enzymatic activity is discussed.
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Ciclopentanos/metabolismo , Nicotiana/metabolismo , Oxilipinas/metabolismo , Reguladores del Crecimiento de las Plantas/biosíntesis , Proteínas de Plantas/metabolismo , Proteínas Quinasas/metabolismo , Ácidos Grasos Insaturados/metabolismo , Nicotiana/enzimologíaRESUMEN
The plant hormone jasmonic acid (JA) plays a pivotal role in plant-insect interactions. Herbivore attack usually elicits dramatic increases in JA concentrations, which in turn activate the accumulation of metabolites that function as defenses against herbivores. Although almost all enzymes involved in the biosynthesis pathway of JA have been identified and characterized, the mechanism by which plants regulate JA biosynthesis remains unclear. Calcium-dependent protein kinases (CDPKs) are plant-specific proteins that sense changes in [Ca(2+)] to activate downstream responses. We created transgenic Nicotiana attenuata plants, in which two CDPKs, NaCDPK4 and NaCDPK5, were simultaneously silenced (IRcdpk4/5 plants). IRcdpk4/5 plants were stunted and aborted most of their flower primordia. Importantly, after wounding or simulated herbivory, IRcdpk4/5 plants accumulated exceptionally high JA levels. When NaCDPK4 and NaCDPK5 were silenced individually, neither stunted growth nor high JA levels were observed, suggesting that NaCDPK4 and NaCDPK5 have redundant roles. Attack from Manduca sexta larvae on IRcdpk4/5 plants induced high levels of defense metabolites that slowed M. sexta growth. We found that NaCDPK4 and NaCDPK5 affect plant resistance against insects in a JA- and JA-signaling-dependent manner. Furthermore, IRcdpk4/5 plants showed overactivation of salicylic-acid-induced protein kinase, a mitogen-activated protein kinase involved in various stress responses, and genetic analysis indicated that the increased salicylic-acid-induced protein kinase activity in IRcdpk4/5 plants was a consequence of the exceptionally high JA levels and was dependent on CORONATINE INSENSITIVE1. This work reveals the critical roles of CDPKs in modulating JA homeostasis and highlights the complex duet between JA and mitogen-activated protein kinase signaling.
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Ciclopentanos/metabolismo , Silenciador del Gen , Herbivoria/fisiología , Nicotiana/enzimología , Oxilipinas/metabolismo , Proteínas de Plantas/genética , Proteínas Quinasas/genética , Regulación hacia Arriba , Animales , Flores/enzimología , Técnicas de Silenciamiento del Gen , Manduca/fisiología , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Modelos Biológicos , Datos de Secuencia Molecular , Proteínas de Plantas/metabolismo , Tallos de la Planta/enzimología , Proteínas Quinasas/metabolismo , Transducción de Señal , Nicotiana/crecimiento & desarrollo , Nicotiana/parasitología , Nicotiana/fisiologíaRESUMEN
OBJECTIVE: To explore the assessment methods of dysphagia. METHODS: The data of 37 patients with dysphagia were retrospectively analyzed. These patients took the Kubota drinking test, Tengdao's evaluation, videofluoroscopic swallowing study (VFSS) and fiberoptic endoscopic evaluation of swallowing (FEES). RESULTS: Fourteen out of thirty-seventh patients showed abnormal results during Kubota drinking test. Tengdao's evaluation results showed that 29/37 patients were abnormal. There 27/37 and 33/37 patients showed abnormalities in positive-aspiration score and swallow dysfunction score of VFSS. The number of abnormal patients in aspiration score of FEES was 19/21. The Kappa values were 0.137, 0.416 between Kubota drinking test. Tengdao's evaluation and VFSS. The FEES was measured against the VFSS for sensibility, specificity, positive predictive value, and negative predictive value, the values were 88.9%, 66.7%, 94.1% and 50.0%. CONCLUSIONS: Kubota drinking test and Tengdao's evaluation can be applied for screening purpose and evaluating result after treatment; VFSS and FEES can be used as more accurate assessments, they can study the dysphagia's character, position and severity. The combination of a variety of dysphagia evaluation methods is the most important basis for diagnosis and treatment of deglutition disorders.
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Trastornos de Deglución/diagnóstico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Deglución , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto JovenRESUMEN
Sodium/proton exchangers (NHX antiporters) play important roles in plant responses to salt stress. Previous research showed that hydrophilic C-terminal region of Arabidopsis AtNHX1 negatively regulates the Na(+)/H(+) transporting activity. In this study, CkNHX1 were isolated from Caragana korshinskii, a pea shrub with high tolerance to salt, drought, and cold stresses. Transcripts of CkNHX1 were detected predominantly in roots, and were significantly induced by NaCl stress in stems. Transgenic yeast and Arabidopsisthalianasos3-1 (Atsos3-1) mutant over-expressing CkNHX1 and its hydrophilic C terminus-truncated derivative, CkNHX1-ΔC, were generated and subjected to NaCl and LiCl stresses. Expression of CkNHX1 significantly enhanced the resistance to NaCl and LiCl stresses in yeast and Atsos3-1 mutant. Whereas, compared with expression of CkNHX1, the expression of CkNHX1-ΔC had much less effect on NaCl tolerance in Atsos3-1 and LiCl tolerance in yeast and Atsos3-1. All together, these results suggest that the predominant expression of CkNHX1 in roots might contribute to keep C. korshinskii adapting to the high salt condition in this plant's living environment; CkNHX1 could recover the phenotype of Atsos3-1 mutant; and the hydrophilic C-terminal region of CkNHX1 should be required for Na(+)/H(+) and Li(+)/H(+) exchanging activity of CkNHX1.
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Caragana/fisiología , Cloruro de Litio/metabolismo , Tolerancia a la Sal/genética , Cloruro de Sodio/metabolismo , Intercambiadores de Sodio-Hidrógeno/biosíntesis , Estrés Fisiológico/genética , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Caragana/genética , Interacciones Hidrofóbicas e Hidrofílicas , Plantas Modificadas Genéticamente , Estructura Terciaria de Proteína , Saccharomyces cerevisiae/genética , Intercambiadores de Sodio-Hidrógeno/química , Intercambiadores de Sodio-Hidrógeno/genéticaRESUMEN
Almost a decade ago BRI1-associated kinase 1 (BAK1) was identified as a co-receptor of brassinosteroid (BR) insensitive 1 (BRI1), the receptor for BRs, which plays an essential role in transducing BR signaling to regulate plant development. BAK1 is also critical in resistance to various pathogens. BAK1 rapidly binds to certain receptors for pathogen/microbeassociated molecular patterns (PAMPs/MAMPs) after the perception of pathogen elicitors and is required for the full elicitation of pathogen-induced defense responses, such as the activation of the mitogen-activated protein kinase 6 (MPK6) and production of reactive oxygen species. Thus, BAK1 functions in both BR signaling and PAMP-triggered immunity (PTI). Recently BAK1 was also found to play an important role in mediating defense responses against an insect herbivore (Manduca sexta) of Nicotiana attenuata. In this interaction, BAK1 positively modulates wound- or herbivore feeding induced accumulation of jasmonic acid (JA) and JA-isoleucine (JA-Ile). This mini-review summarizes recent advances in our understanding of the functions of BAK1 in resistance to pathogens and herbivores.
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Insectos/patogenicidad , Inmunidad de la Planta/fisiología , Proteínas de Plantas/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Animales , Regulación de la Expresión Génica de las Plantas/genética , Regulación de la Expresión Génica de las Plantas/fisiología , Inmunidad de la Planta/genética , Proteínas de Plantas/genética , Proteínas Serina-Treonina Quinasas/genética , Nicotiana/genética , Nicotiana/metabolismo , Nicotiana/parasitologíaRESUMEN
BAK1 is a co-receptor of brassinosteroid (BR) receptor BRI1, and plays a well-characterized role in BR signalling. BAK1 also physically interacts with the flagellin receptor FLS2 and regulates pathogen resistance. The role of BAK1 in mediating Nicotiana attenuata's resistance responses to its specialist herbivore, Manduca sexta, was examined here. A virus-induced gene-silencing system was used to generate empty vector (EV) and NaBAK1-silenced plants. The wounding- and herbivory-induced responses were examined on EV and NaBAK1-silenced plants by wounding plants or simulating herbivory by treating wounds with larval oral secretions (OS). After wounding or OS elicitation, NaBAK1-silenced plants showed attenuated jasmonic acid (JA) and JA-isoleucine bursts, phytohormone responses important in mediating plant defences against herbivores. However, these decreased JA and JA-Ile levels did not result from compromised MAPK activity or elevated SA levels. After simulated herbivory, NaBAK1-silenced plants had EV levels of defensive secondary metabolites, namely, trypsin proteinase inhibitors (TPIs), and similar levels of resistance to Manduca sexta larvae. Additional experiments demonstrated that decreased JA levels in NaBAK1-VIGS plants, rather than the enzymatic activity of JAR proteins or Ile levels, were responsible for the reduced JA-Ile levels observed in these plants. Methyl jasmonate application elicited higher levels of TPI activity in NaBAK1-silenced plants than in EV plants, suggesting that silencing NaBAK1 enhances the accumulation of TPIs induced by a given level of JA. Thus NaBAK1 is involved in modulating herbivory-induced JA accumulation and how JA levels are transduced into TPI levels in N. attenuata.
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Ciclopentanos/metabolismo , Regulación de la Expresión Génica de las Plantas , Manduca/fisiología , Nicotiana/metabolismo , Oxilipinas/metabolismo , Proteínas de Plantas/metabolismo , Inhibidores de Tripsina/metabolismo , Animales , Proteínas de Plantas/genética , Nicotiana/genética , Nicotiana/parasitología , Inhibidores de Tripsina/genéticaRESUMEN
OBJECTIVE: To investigate the differences of olfactory bulb (OB) volumes between younger and older, male and female, left-side and right-side in healthy middle and old-aged persons by MRI. METHODS: Ninety five healthy middle and old-aged volunteers (male:female = 45:50) were divided into 2 groups, group one included persons aged from 50 to 69, group two included persons elder than 70. The left-side, right-side and both-side volumes of OB, the volumes of brain and the ratio of OB/brain were measured by MRI. RESULTS: (1) The left-side and both-side volumes of OB (x(-) +/- s), the volumes of brain [(39.89 +/- 8.7) mm(3), (81.70 +/- 16.8) mm(3) and (1281.86 +/- 140.2) cm(3)] in 50 - 69 years old group were respectively larger than those in >/= 70 years old group [(34.45 +/- 10.4) mm(3), (72.10 +/- 19.3) mm(3) and (1165.77 +/- 165.3) cm(3)], and the differences reached statistical significance (t were respectively 2.649, 2.449, 3.516, all P < 0.05). There were no significant differences of right-side OB volumes and the ratio of OB/brain between 50 - 69 years old group and >/= 70 years old group (t were respectively 1.904, 0.616, each P > 0.05). (2) The male's OB volumes of left-side, right-side and both-side, the brain volumes and the ratio of OB/brain were respectively larger than females', and the differences reached statistical significance (t were respectively 4.461, 3.630, 4.399, 3.800, 2.400, all P < 0.05). (3) The right-side OB volumes were larger than left-side's and significant differences were found in female group, 50 - 60 years old group and >/= 70 years old group (t were respectively 2.732, 2.117, 3.516, all P < 0.05). There were no significant differences of OB volumes between left-side and right-side in female (t = 2.649, P = 0.110). The ratio of right-side OB/brain were larger than the ratio of left-side's and the differences reached statistical significance (t = 3.183, P = 0.002). CONCLUSIONS: MRI could be used to measure the volume of OB. The older the people, the smaller the OB volumes. There was no influence of age on the ratio OB/brain. The OB volumes of right-side were larger than those of left-side. The OB volumes of male were larger than those of female.
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Bulbo Olfatorio , Olfato , Humanos , Imagen por Resonancia MagnéticaRESUMEN
OBJECTIVE: To analyze the clinical features and treatment protocols of otogenic intracranial complications in Peking Union Medical College Hospital. METHODS: Retrospective study of 14 patients (10 males and 4 females, aged between 12 - 62 years, mean age 32.1 years) hospitalized from 1982 - 2006. Twelve cases were otitis media (OM) with cholesteatoma, the other 2 cases were non-cholesteatomatous OM. All the otogenic intracranial complications located at the same sides as otologic disorders. Brain abscess was the most common type of otogenic complications and Proteus was the most common microorganism detected. Suppurative ear discharge, headache, high fever and nausea with vomiting were the most common clinical manifestations with very high incidences. All the patients received combined protocols of mastoid surgeries and antibiotics treatment. RESULTS: All the 14 patients recovered clinically. For patients discharged before 1987, there were 4 patients followed up for 22.5 - 24.4 years with a mean time of 23.8 without recurrence, 1 patient died of cardiovascular disease 19.2 years later after discharge, 4 patients lost follow-up. For the 5 patients discharged after 1997, brain abscess recurred in one patient with pseudo-recovery after 24 days and he fully recovered after re-hospitalization and treatment. All the five patients were followed up for 1.5 years to 10.6 years with a mean time of 6.5 years without recurrence. CONCLUSIONS: Youngsters and males seemed to be more vulnerable. Brain abscess was the most common intracranial complication and Proteus was the most common pyogenic microorganism. Combination of mastoid surgery and antibiotics were essential for effectively controlling the intracranial complications and improving the recovery. CT and MRI were essential for correct diagnosis bedtimes and MRI seemed to have a better performance.
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Absceso Encefálico/etiología , Enfermedades del Oído/complicaciones , Adolescente , Adulto , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Otitis Media/complicaciones , Estudios Retrospectivos , Adulto JovenRESUMEN
OBJECTIVE: ApneaGragh is a new device for simultaneous determination of obstructive sleep apnoeic events and continuous pressure measurements for localization of upper airway obstructive site. This study is to evaluate the clinical value of it. METHODS: From April to October in 2006, 32 obstructive sleep apnea (OSA) patients diagnosed by polysomnography (PSG) were examined by two methods: Endoscopy with müller's maneuver at daytime and continuous upper airway pressure recording with ApneaGraph at night in Peking Union Medical College Hospital. The upper airway obstructive sites determined by the two methods were compared. ApneaGraph transducer catheter contains two pressure sensors and two temperature sensors used for obstruction site determination and detection of apnoeic events during sleep. Obstructive sites were divided into upper (retropalatal oropharynx) or lower level (retroglossal region). The lower limit of upper airway obstruction was determined by observed pressure pattern. Used constituent retio to reflect the obstructive proportion of different levels. The apnea hypopnea index (AHI) measured by PSG and ApneaGraph were also compared. RESULTS: Two patterns of obstruction were observed in our group: 1. The site of obstruction was located only at the upper level. 2. The obstruction of upper and lower level all present. Site of obstruction determined by Apneagraph: 28 (87.5%) cases had predominant sites of obstructions in upper level (the constituent retio of retropalatal obstruction > 50%), the others in lower level (the constituent retio of retroglossal obstruction > 50%). Endoscopy localization of obstruction: 18 cases had retropalatal obstructions alone, 13 cases had obstructions of retropalate combined with retroglossa, only 1 patient didn't have obstruction. Defined the constituent retio higher than thirty percent the criteria of obstruction, then identical results were obtained by both methods in retropalatal segment in 27 (84.4%) of the patients, while in only 17 (53.1%) obstructions was determined by the both methods in retroglossal areas. The polysomnograpic AHI (x +/- s) was 52.2 +/- 18.1, versus 50.2 +/- 16.0 obtained by ApneaGraph. There was a significant correlation between them (r = 0.876, P < 0.001). CONCLUSIONS: ApneaGraph can identify the level of upper airway obstruction more accurate than fiberoptic pharyngoscopy. In the meantime, it also can serve as a portable PSG to diagnose sleep disordered breathing qualitatively.
Asunto(s)
Presión de las Vías Aéreas Positiva Contínua/instrumentación , Monitoreo Ambulatorio/instrumentación , Polisomnografía/instrumentación , Apnea Obstructiva del Sueño/diagnóstico , Adulto , Anciano , Presión de las Vías Aéreas Positiva Contínua/métodos , Endoscopía/métodos , Humanos , Persona de Mediana Edad , Monitoreo Ambulatorio/métodos , Polisomnografía/métodos , Apnea Obstructiva del Sueño/fisiopatología , Adulto JovenRESUMEN
OBJECTIVE: Severe nasopharyngeal stenosis (NPS) is a rare complication of uvulopalatopharyngoplasty (UPPP) and very difficult to manage. This report presents our successful treatment experience. METHODS: From Nov 1997 to Feb 2006, 6 adults patients with NPS secondary to UPPP were treated in Peking Union Hospital. Two cases was grade II stenosis, received surgery of local pharyngeal and soft palate mucosa flap rotation to enlarge nasopharyngeal airway with stenosis; For the remaining 4 cases with more severe NPS (grade III) who had received 1-3 times unsuccessful repair procedures previously, prolonged nasopharyngeal hollow obturators were used for 6 months after stenosis repair surgery. RESULTS: With 9-48 months follow-up, All cases results were satisfactory. Nasal obstruction symptom was eliminated, NPS corrected, no velopharyngeal insufficiency complication happened. Daytime removable nasopharyngeal hollow stent obturators with palate support device is more comfortable for patients. CONCLUSIONS: Local flap rotation to enlarge stenosis airway and prolonged use nasopharyngeal hollow obturators are reliable methods of correction NPS following UPPP.