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1.
Nanoscale Adv ; 5(18): 4696-4702, 2023 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-37705792

RESUMEN

Germanium (Ge) is increasingly used as a substrate for high-performance optoelectronics, photovoltaics, and electronic devices. These devices are usually grown on thick and rigid Ge substrates manufactured by classical wafering techniques. Nanomembranes (NMs) provide an alternative to this approach while offering wafer-scale lateral dimensions, weight reduction, waste limitation, and cost effectiveness. Herein, we introduce the Porous germanium Efficient Epitaxial LayEr Release (PEELER) process, which consists of the fabrication of wafer-scale detachable Ge NMs on porous Ge (PGe) and substrate reuse. We demonstrate the growth of Ge NMs with monocrystalline quality as revealed by high-resolution transmission electron microscopy (HRTEM) characterization. Together with the surface roughness below 1 nm, it makes the Ge NMs suitable for growth of III-V materials. Additionally, the embedded nanoengineered weak layer enables the detachment of the Ge NMs. Finally, we demonstrate the wet-etch-reconditioning process of the Ge substrate, allowing its reuse, to produce multiple free-standing NMs from a single parent wafer. The PEELER process significantly reduces the consumption of Ge in the fabrication process, paving the way for a new generation of low-cost flexible optoelectronic devices.

2.
Preprint en Inglés | bioRxiv | ID: ppbiorxiv-479285

RESUMEN

BackgroundThe rapid spread of the SARS-CoV-2 Omicron (B.1.1.529) variant, including in highly vaccinated populations, has raised important questions about the efficacy of current vaccines. Immune correlates of vaccine protection against Omicron are not known. Methods30 cynomolgus macaques were immunized with homologous and heterologous prime-boost regimens with the mRNA-based BNT162b2 vaccine and the adenovirus vector-based Ad26.COV2.S vaccine. Following vaccination, animals were challenged with the SARS-CoV-2 Omicron variant by the intranasal and intratracheal routes. ResultsOmicron neutralizing antibodies were observed following the boost immunization and were higher in animals that received BNT162b2, whereas Omicron CD8+ T cell responses were higher in animals that received Ad26.COV2.S. Following Omicron challenge, sham controls showed more prolonged virus in nasal swabs than in bronchoalveolar lavage. Vaccinated macaques demonstrated rapid control of virus in bronchoalveolar lavage, and most vaccinated animals also controlled virus in nasal swabs, showing that current vaccines provide substantial protection against Omicron in this model. However, vaccinated animals that had moderate levels of Omicron neutralizing antibodies but negligible Omicron CD8+ T cell responses failed to control virus in the upper respiratory tract. Virologic control correlated with both antibody and T cell responses. ConclusionsBNT162b2 and Ad26.COV2.S provided robust protection against high-dose challenge with the SARS-CoV-2 Omicron variant in macaques. Protection against this highly mutated SARS-CoV-2 variant correlated with both humoral and cellular immune responses.

3.
Preprint en Inglés | bioRxiv | ID: ppbiorxiv-479037

RESUMEN

SARS-CoV-2 Omicron is highly transmissible and has substantial resistance to antibody neutralization following immunization with ancestral spike-matched vaccines. It is unclear whether boosting with Omicron-specific vaccines would enhance immunity and protection. Here, nonhuman primates that received mRNA-1273 at weeks 0 and 4 were boosted at week 41 with mRNA-1273 or mRNA-Omicron. Neutralizing antibody titers against D614G were 4760 and 270 reciprocal ID50 at week 6 (peak) and week 41 (pre-boost), respectively, and 320 and 110 for Omicron. Two weeks after boost, titers against D614G and Omicron increased to 5360 and 2980, respectively, for mRNA-1273 and 2670 and 1930 for mRNA-Omicron. Following either boost, 70-80% of spike-specific B cells were cross-reactive against both WA1 and Omicron. Significant and equivalent control of virus replication in lower airways was observed following either boost. Therefore, an Omicron boost may not provide greater immunity or protection compared to a boost with the current mRNA-1273 vaccine.

4.
Mil Med ; 187(5-6): e726-e734, 2022 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-33647979

RESUMEN

INTRODUCTION: The history of the use of telemedicine in maritime medicine dates back to the 1930s. In the early 2000s, the German Navy built up a telemedicine network which today is installed in all ships and provides a connection to the medical infrastructure ashore. The objective of this study was to optimize the implementation of telemedicine based on the experience gained in the German Navy. For this purpose, qualitative and quantitative methods were used to identify determinants which affect the use of telemedicine in order to determine whether there is any need for optimization. METHODS: The study was conducted using a mixed methods design. First, guideline-based interviews were conducted with Navy medical officers who had been recruited via various email distribution lists. The interviews were then transcribed and coded. In an analysis, deductive and inductive categories were derived from the codes. Hypotheses were deduced from the interviews, too, and used to develop a questionnaire.Besides the medical officers, other Navy medical personnel with experience in the field of telemedicine took part in the survey. The study was concluded by a descriptive analysis of the quantitative data. RESULTS: The analysis of the interviews revealed that a regular use of telemedicine workstations increased the users' confidence and, in their opinion, improved medical treatment. Technical and organizational problems posed obstacles, which increased the use of partly insecure alternatives. A proper technical support was regarded as a precondition for effectively using telemedicine.The results of the quantitative analysis showed that consultation was mainly sought for dermatological (46%), surgical (24%), and internal (22%) conditions. CONCLUSION: The study revealed determinants for the use of telemedicine in the German Navy. Factors improving the motivation of the users should be strengthened in order to optimize the use of telemedicine. Furthermore, it can be assumed that a successful implementation will be supported by reducing or eliminating obstacles. The findings on the main reasons for seeking medical advice could be taken into account in the further planning of specific training.


Asunto(s)
Telemedicina , Humanos , Derivación y Consulta , Navíos
5.
Front Plant Sci ; 12: 745579, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34594354

RESUMEN

Cereals represent an important source of beneficial compounds for human health, such as macro- and micronutrients, vitamins, and bioactive molecules. Generally, the consumption of whole-grain products is associated with significant health benefits, due to the elevated amount of dietary fiber (DF). However, the consumption of whole-grain foods is still modest compared to more refined products. In this sense, it is worth focusing on the increase of DF fractions inside the inner compartment of the seed, the endosperm, which represents the main part of the derived flour. The main components of the grain fiber are arabinoxylan (AX), ß-glucan (ßG), and resistant starch (RS). These three components are differently distributed in grains, however, all of them are represented in the endosperm. AX and ßG, classified as non-starch polysaccharides (NSP), are in cell walls, whereas, RS is in the endosperm, being a starch fraction. As the chemical structure of DFs influences their digestibility, the identification of key actors involved in their metabolism can pave the way to improve their function in human health. Here, we reviewed the main achievements of plant biotechnologies in DFs manipulation in cereals, highlighting new genetic targets to be exploited, and main issues to face to increase the potential of cereals in fighting malnutrition.

6.
Preprint en Inglés | bioRxiv | ID: ppbiorxiv-456316

RESUMEN

The CVnCoV (CureVac) mRNA vaccine for SARS-CoV-2 has recently been evaluated in a phase 2b/3 efficacy trial in humans. CV2CoV is a second-generation mRNA vaccine with optimized non-coding regions and enhanced antigen expression. Here we report a head-to-head study of the immunogenicity and protective efficacy of CVnCoV and CV2CoV in nonhuman primates. We immunized 18 cynomolgus macaques with two doses of 12 ug of lipid nanoparticle formulated CVnCoV, CV2CoV, or sham (N=6/group). CV2CoV induced substantially higher binding and neutralizing antibodies, memory B cell responses, and T cell responses as compared with CVnCoV. CV2CoV also induced more potent neutralizing antibody responses against SARS-CoV-2 variants, including B.1.351 (beta), B.1.617.2 (delta), and C.37 (lambda). While CVnCoV provided partial protection against SARS-CoV-2 challenge, CV2CoV afforded robust protection with markedly lower viral loads in the upper and lower respiratory tract. Antibody responses correlated with protective efficacy. These data demonstrate that optimization of non-coding regions can greatly improve the immunogenicity and protective efficacy of an mRNA SARS-CoV-2 vaccine in nonhuman primates.

7.
Preprint en Inglés | bioRxiv | ID: ppbiorxiv-456015

RESUMEN

Neutralizing antibody responses gradually wane after vaccination with mRNA-1273 against several variants of concern (VOC), and additional boost vaccinations may be required to sustain immunity and protection. Here, we evaluated the immune responses in nonhuman primates that received 100 {micro}g of mRNA-1273 vaccine at 0 and 4 weeks and were boosted at week 29 with mRNA-1273 (homologous) or mRNA-1273.{beta} (heterologous), which encompasses the spike sequence of the B.1.351 (beta or {beta}) variant. Reciprocal ID50 pseudovirus neutralizing antibody geometric mean titers (GMT) against live SARS-CoV-2 D614G and the {beta} variant, were 4700 and 765, respectively, at week 6, the peak of primary response, and 644 and 553, respectively, at a 5-month post-vaccination memory time point. Two weeks following homologous or heterologous boost {beta}-specific reciprocal ID50 GMT were 5000 and 3000, respectively. At week 38, animals were challenged in the upper and lower airway with the {beta} variant. Two days post-challenge, viral replication was low to undetectable in both BAL and nasal swabs in most of the boosted animals. These data show that boosting with the homologous mRNA-1273 vaccine six months after primary immunization provides up to a 20-fold increase in neutralizing antibody responses across all VOC, which may be required to sustain high-level protection against severe disease, especially for at-risk populations. One-sentence summarymRNA-1273 boosted nonhuman primates have increased immune responses and are protected against SARS-CoV-2 beta infection.

8.
Preprint en Inglés | bioRxiv | ID: ppbiorxiv-452733

RESUMEN

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is the causative agent of the COVID-19 global pandemic. SARS-CoV-2 is an enveloped RNA virus that relies on its trimeric surface glycoprotein, spike, for entry into host cells. Here we describe the COVID-19 vaccine candidate MV-014-212, a live attenuated, recombinant human respiratory syncytial virus (RSV) expressing a chimeric SARS-CoV-2 spike as the only viral envelope protein. MV-014-212 was attenuated and immunogenic in African green monkeys (AGMs). One mucosal administration of MV-014-212 in AGMs protected against SARS-CoV-2 challenge, reducing by more than 200- fold the peak shedding of SARS-CoV-2 in the nose. MV-014-212 elicited mucosal immunity in the nose and neutralizing antibodies in serum that exhibited cross-neutralization against two virus variants of concern. Intranasally delivered, live attenuated vaccines such as MV-014-212 entail low-cost manufacturing suitable for global deployment. MV-014-212 is currently in phase 1 clinical trials as a single-dose intranasal COVID-19 vaccine.

9.
Acta Inform Med ; 29(1): 4-9, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34012206

RESUMEN

BACKGROUND: Universities have halted non-essential services, with many restricting campus-based teaching, and continuing courses through online resources, including (controversially) lab-work. Such technologically enhanced approaches have been proven to have high levels of engagement among university students. OBJECTIVE: This study focuses on the perception of quality of online learning by first-year university students, between two semesters, amidst the COVID-19 pandemic. METHODS: A 24-item questionnaire was designed with Likert response scale. It consisted of general perception questions of academic life and questions specific to the quality of delivery of a specific class. Eighty one eligible students were asked to fill the same questionnaire for each semester. Students' responses and their grades from the final exams in each semester were compared. RESULTS: Out of 81 eligible students, 75.31% of students responded to the survey. They were less interested in their studies in the second "online" semester (p=0.05). Students expressed dissatisfaction with the quality of online classes (p=0.03). Academic life fulfillment was also affected (p=0.02). Students' perception of the amount of free time they had between semesters did not change significantly (p=0.16). Students appeared dissatisfied with their active participation during the online class (p=0.007), even though they felt less stressed attending lectures from home (p=0.041). However, they found that workload was bearable and similar between semesters (p=0.83). Students also had significantly more trouble concentrating during online lectures (p<0.001). Students' grades significantly improved by an average of 1.07 (out of 10) in the final exams at the end of the second semester (p<0.001). CONCLUSION: These unprecedented circumstances require innovation and cooperation on the part of university programs to maintain rigorous standards of higher education, taking into account students' evolving perception and needs.

10.
Preprint en Inglés | bioRxiv | ID: ppbiorxiv-440647

RESUMEN

Immune correlates of protection can be used as surrogate endpoints for vaccine efficacy. The nonhuman primate (NHP) model of SARS-CoV-2 infection replicates key features of human infection and may be used to define immune correlates of protection following vaccination. Here, NHP received either no vaccine or doses ranging from 0.3 - 100 g of mRNA-1273, a mRNA vaccine encoding the prefusion-stabilized SARS-CoV-2 spike (S-2P) protein encapsulated in a lipid nanoparticle. mRNA-1273 vaccination elicited robust circulating and mucosal antibody responses in a dose-dependent manner. Viral replication was significantly reduced in bronchoalveolar lavages and nasal swabs following SARS-CoV-2 challenge in vaccinated animals and was most strongly correlated with levels of anti-S antibody binding and neutralizing activity. Consistent with antibodies being a correlate of protection, passive transfer of vaccine-induced IgG to naive hamsters was sufficient to mediate protection. Taken together, these data show that mRNA-1273 vaccine-induced humoral immune responses are a mechanistic correlate of protection against SARS-CoV-2 infection in NHP. One-Sentence SummarymRNA-1273 vaccine-induced antibody responses are a mechanistic correlate of protection against SARS-CoV-2 infection in NHP.

11.
Plant Cell Environ ; 44(3): 931-947, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33314180

RESUMEN

Recognition at the plasma membrane of danger signals (elicitors) belonging to the classes of the microbe/pathogen- and damage-associated molecular patterns is a key event in pathogen sensing by plants and is associated with a rapid activation of immune responses. Different cellular compartments, including plasma membrane, chloroplasts, nuclei and mitochondria, are involved in the immune cellular program. However, how pathogen sensing is transmitted throughout the cell remains largely to be uncovered. Arabidopsis NPK1-related Proteins (ANPs) are mitogen-activated protein kinase kinase kinases previously shown to have a role in immunity. In this article, we studied the in vivo intracellular dynamics of ANP1- and ANP3-GFP fusions and found that under basal physiological conditions both proteins are present in the cytosol, while ANP3 is also localized in mitochondria. After elicitor perception, both proteins are present also in the plastids and nuclei, revealing a localization pattern that is so far unique. The N-terminal region of the protein kinases is responsible for their localization in mitochondria and plastids. Moreover, we found that the localization of ANPs coincides with the sites of elicitor-induced ROS accumulation and that plants lacking ANP function do not accumulate intracellular ROS.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimología , Quinasas Quinasa Quinasa PAM/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Arabidopsis/inmunología , Arabidopsis/metabolismo , Western Blotting , Núcleo Celular/metabolismo , Microscopía Confocal , Plantas Modificadas Genéticamente , Plastidios/metabolismo , Fracciones Subcelulares/metabolismo , Transcriptoma
12.
Int J Mol Sci ; 20(22)2019 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-31739436

RESUMEN

Macro- and micronutrients, essential for the maintenance of human metabolism, are assimilated daily through the diet. Wheat and other major cereals are a good source of nutrients, such as carbohydrates and proteins, but cannot supply a sufficient amount of essential micronutrients, including provitamin A. As vitamin A deficiency (VAD) leads to several serious diseases throughout the world, the biofortification of a major staple crop, such as wheat, represents an effective way to preserve human health in developing countries. In the present work, a key enzyme involved in the branch of carotenoids pathway producing ß-carotene, lycopene epsilon cyclase, has been targeted by a Targeting Induced Local Lesions in Genomes (TILLING) approach in a "block strategy" perspective. The null mutant genotype showed a strong reduction in the expression of the lcyE gene and also interesting pleiotropic effects on an enzyme (ß-ring hydroxylase) acting downstream in the pathway. Biochemical profiling of carotenoids in the wheat mutant lines showed an increase of roughly 75% in ß-carotene in the grains of the complete mutant line compared with the control. In conclusion, we describe here the production and characterization of a new wheat line biofortified with provitamin A obtained through a nontransgenic approach, which also sheds new light on the molecular mechanism governing carotenoid biosynthesis in durum wheat.


Asunto(s)
Biofortificación , Ingeniería Genética , Triticum/genética , Triticum/metabolismo , Vitamina A/metabolismo , Alelos , Secuencia de Bases , Carotenoides/metabolismo , Regulación de la Expresión Génica de las Plantas , Marcación de Gen , Ingeniería Genética/métodos , Genómica/métodos , Humanos , Liasas Intramoleculares/genética , Liasas Intramoleculares/metabolismo , Mutación , Filogenia , Plantas Modificadas Genéticamente
13.
Methods Mol Biol ; 1578: 25-38, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28220413

RESUMEN

Oligogalacturonides (OGs) are pectic fragments derived from the partial degradation of homogalacturonan in the plant cell wall and able to elicit plant defence responses. Recent methodological advances in the isolation of OGs from plant tissues and their characterization have confirmed their role as bona fide plant Damage-Associated Molecular Patterns. Here, we describe the methods for the isolation of OGs from Arabidopsis leaf tissues and for the characterization of OG structure and biological activity.


Asunto(s)
Arabidopsis/metabolismo , Pectinas/química , Péptidos/aislamiento & purificación , Arabidopsis/inmunología , Proteínas de Arabidopsis/análisis , Proteínas de Arabidopsis/química , Pared Celular/química , Pared Celular/metabolismo , Pectinas/análisis , Péptidos/química , Inmunidad de la Planta , Hojas de la Planta/química , Hojas de la Planta/metabolismo , Conformación Proteica
14.
Mol Plant Pathol ; 18(4): 582-595, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-27118426

RESUMEN

Plants possess an innate immune system capable of restricting invasion by most potential pathogens. At the cell surface, the recognition of microbe-associated molecular patterns (MAMPs) and/or damage-associated molecular patterns (DAMPs) by pattern recognition receptors (PRRs) represents the first event for the prompt mounting of an effective immune response. Pathogens have evolved effectors that block MAMP-triggered immunity. The Pseudomonas syringae effector AvrPto abolishes immunity triggered by the peptide MAMPs flg22 and elf18, derived from the bacterial flagellin and elongation factor Tu, respectively, by inhibiting the kinase function of the corresponding receptors FLS2 and EFR, as well as their co-receptors BAK1 and BKK1. Oligogalacturonides (OGs), a well-known class of DAMPs, are oligomers of α-1,4-linked galacturonosyl residues, released on partial degradation of the plant cell wall homogalacturonan. We show here that AvrPto affects only a subset of the OG-triggered immune responses and that, among these responses, only a subset is affected by the concomitant loss of BAK1 and BKK1. However, the antagonistic effect on auxin-related responses is not affected by either AvrPto or the loss of BAK1/BKK1. These observations reveal an unprecedented complexity among the MAMP/DAMP response cascades. We also show that the signalling system mediated by Peps, another class of DAMPs, and their receptors PEPRs, contributes to OG-activated immunity. We hypothesize that OGs are sensed through multiple and partially redundant perception/transduction complexes, some targeted by AvrPto, but not necessarily comprising BAK1 and BKK1.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/inmunología , Arabidopsis/metabolismo , Proteínas Bacterianas/metabolismo , Ácidos Hexurónicos/farmacología , Inmunidad de la Planta , Arabidopsis/genética , Arabidopsis/microbiología , Botrytis , Resistencia a la Enfermedad/efectos de los fármacos , Flagelina/farmacología , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Genes de Plantas , Glucanos/metabolismo , Ácidos Indolacéticos/metabolismo , Enfermedades de las Plantas/microbiología , Inmunidad de la Planta/efectos de los fármacos , Inmunidad de la Planta/genética , Plantas Modificadas Genéticamente , Pseudomonas syringae/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Plantones/efectos de los fármacos , Plantones/genética , Plantones/microbiología
15.
Plant J ; 84(6): 1073-86, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26485342

RESUMEN

Plant immunity against pathogens is achieved through rapid activation of defense responses that occur upon sensing of microbe- or damage-associated molecular patterns, respectively referred to as MAMPs and DAMPs. Oligogalacturonides (OGs), linear fragments derived from homogalacturonan hydrolysis by pathogen-secreted cell wall-degrading enzymes, and flg22, a 22-amino acid peptide derived from the bacterial flagellin, represent prototypical DAMPs and MAMPs, respectively. Both types of molecules induce protection against infections. In plants, like in animals, calcium is a second messenger that mediates responses to biotic stresses by activating calcium-binding proteins. Here we show that simultaneous loss of calcium-dependent protein kinases CPK5, CPK6 and CPK11 affects Arabidopsis thaliana basal as well as elicitor- induced resistance to the necrotroph Botrytis cinerea, by affecting pathogen-induced ethylene production and accumulation of the ethylene biosynthetic enzymes 1-aminocyclopropane-1-carboxylic acid (ACC) synthase 2 (ACS2) and 6 (ACS6). Moreover, ethylene signaling contributes to OG-triggered immunity activation, and lack of CPK5, CPK6 and CPK11 affects the duration of OG- and flg22-induced gene expression, indicating that these kinases are shared elements of both DAMP and MAMP signaling pathways.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Botrytis/metabolismo , Etilenos/biosíntesis , Enfermedades de las Plantas/microbiología , Proteínas Quinasas/metabolismo , Arabidopsis/inmunología , Proteínas de Arabidopsis/genética , Regulación de la Expresión Génica de las Plantas , Mutación , Enfermedades de las Plantas/inmunología , Hojas de la Planta/metabolismo , Hojas de la Planta/microbiología , Proteínas Quinasas/clasificación , Proteínas Quinasas/genética , Plantones , Transducción de Señal/fisiología
16.
Plant Physiol ; 165(3): 1188-1202, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24812107

RESUMEN

Plant immunity is activated through complex and cross-talking transduction pathways that include a mitogen-activated protein kinase phosphorylation cascade. Here, we have investigated the role in immunity of the Arabidopsis (Arabidopsis thaliana) gene subfamily that encodes the mitogen-activated protein triple kinases indicated as ARABIDOPSIS NUCLEUS- AND PHRAGMOPLAST-LOCALIZED KINASE1-RELATED PROTEIN KINASE1 (ANP1), ANP2, and ANP3. For this study, we used representative danger signals (elicitors) belonging to the classes of the damage- and pathogen-associated molecular patterns, i.e. oligogalacturonides, linear fragments derived from the plant cell wall homogalacturonan, and the peptide elf18 derived from the bacterial elongation factor thermo-unstable. Analyses of single and double as well as conditional triple mutants show that ANPs are required for elicitor-triggered defense responses and protection against the necrotrophic fungus Botrytis cinerea. Notably, ANPs are also required for both the elicitor-induced oxidative burst and the transduction of the hydrogen peroxide signal but not for the inhibition of auxin-induced gene expression, indicating that this response can be uncoupled from the activation of defense responses. Our findings point to ANPs as key transduction elements that coordinate damage- and pathogen-associated molecular pattern-triggered immunity and orchestrate reactive oxygen species accumulation and signaling.

17.
Plant Physiol ; 165(1): 262-76, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24639336

RESUMEN

Transmembrane receptor-like kinases characterized by the presence of one or more lysin motif (LysM) domains in the extracytoplasmic portion (LysM-containing receptor-like kinases [LYKs]) mediate recognition of symbiotic and pathogenic microorganisms in plants. The Arabidopsis (Arabidopsis thaliana) genome encodes five putative LYKs; among them, AtLYK1/CHITIN ELICITOR RECEPTOR KINASE1 is required for response to chitin and peptidoglycan, and AtLYK4 contributes to chitin perception. More recently, AtLYK3 has been shown to be required for full repression, mediated by Nod factors, of Arabidopsis innate immune responses. In this work, we show that AtLYK3 also negatively regulates basal expression of defense genes and resistance to Botrytis cinerea and Pectobacterium carotovorum infection. Enhanced resistance of atlyk3 mutants requires PHYTOALEXIN-DEFICIENT3, which is crucial for camalexin biosynthesis. The expression of AtLYK3 is strongly repressed by elicitors and fungal infection and is induced by the hormone abscisic acid (ABA), which has a negative impact on resistance against B. cinerea and P. carotovorum. Plants lacking a functional AtLYK3 also show reduced physiological responses to ABA and are partially resistant to ABA-induced inhibition of PHYTOALEXIN-DEFICIENT3 expression. These results indicate that AtLYK3 is important for the cross talk between signaling pathways activated by ABA and pathogens.


Asunto(s)
Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimología , Arabidopsis/inmunología , Inmunidad de la Planta , Proteínas Quinasas/metabolismo , Receptor Cross-Talk , Ácido Abscísico/farmacología , Arabidopsis/genética , Arabidopsis/microbiología , Botrytis/efectos de los fármacos , Botrytis/fisiología , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Resistencia a la Enfermedad/inmunología , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Genes de Plantas , Prueba de Complementación Genética , Proteínas Fluorescentes Verdes/metabolismo , Mutación/genética , Oligosacáridos/farmacología , Fenotipo , Enfermedades de las Plantas/inmunología , Enfermedades de las Plantas/microbiología , Inmunidad de la Planta/efectos de los fármacos , Receptor Cross-Talk/efectos de los fármacos , Proteínas Recombinantes de Fusión/metabolismo
18.
FEBS Lett ; 585(11): 1521-8, 2011 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-21536040

RESUMEN

An efficient sensing of danger and a rapid activation of the immune system are crucial for the survival of plants. Conserved pathogen/microbe-associated molecular patterns (PAMPs/MAMPs) and endogenous molecular patterns, which are present only when the tissue is infected or damaged (damage-associated molecular patterns or DAMPs), can act as danger signals and activate the plant immune response. These molecules are recognized by surface receptors that are indicated as pattern recognition receptors (PRRs). In this paper we summarize recent information on oligogalacturonides (OGs), a class of DAMPs that is released from the extracellular matrix of the plant cell during pathogen attack or wounding. We also describe the characteristics of the Arabidopsis Wall-Associated Kinase 1 (WAK1), a PRR recently identified as a receptor of OGs and discuss the use of WAK1, PRRs and chimeric receptors to engineer resistance in crop plants.


Asunto(s)
Ingeniería Genética/métodos , Plantas/genética , Plantas/inmunología , Receptores de Reconocimiento de Patrones/genética , Receptores de Reconocimiento de Patrones/metabolismo , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Secuencia de Aminoácidos , Animales , Proteínas de Arabidopsis/metabolismo , Humanos , Proteínas de la Membrana/metabolismo , Datos de Secuencia Molecular , Pectinas/metabolismo , Plantas/metabolismo , Proteínas Quinasas/metabolismo , Receptores de Reconocimiento de Patrones/química , Proteínas Recombinantes de Fusión/química
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