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1.
Physiol Mol Biol Plants ; 29(1): 1-10, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36733839

RESUMEN

We investigated the role of the DDTFR10/A gene of the ethylene response element-binding protein (EREBP) family through the CRISPR/Cas9 genome editing approach. The associated role of this gene in tomato fruit ripening was known. The involvement of ripening-regulatory proteins in plant defense has been documented; therefore, to find the involvement of the DDTFR10/A gene in host susceptibility, we introduced the mutation in DDTFR10/A gene through CRISPR/cas9 in the genome of the tomato plant. The 50% biallelic and 50% homozygous mutations were observed in the T0 generation. The CRISPR/Cas9 edited plants showed 40% reduced symptoms of Fusarium wilt compared to control plants (non-edited). The DDTFR10/A gene expression in tomato plants was evaluated against biotic (Fusarium wilt) and abiotic (salinity) stresses, and the upregulated expression of this gene was found under both challenges. However, a comparative increase in DDTFR10/A gene expression was observed in tomato plants upon inoculation with Fusarium oxysporum f. sp. lycopersici. The phenotypic assay performed on edited tomato plants demonstrated the role of the DDTFR10/A gene in contributing toward susceptibility against Fusarium wilt. Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-022-01273-6.

2.
Physiol Mol Biol Plants ; 29(12): 1959-1979, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38222284

RESUMEN

Chenopodium quinoa possesses remarkable nutritional value and adaptability to various agroecological conditions. Panicle architecture influences the number of spikelets and grains in a panicle, ultimately leading to productivity and yield. Therefore, this study aimed to investigate the metabolites, nutrients, and minerals in Chenopodium quinoa accessions of varying panicle architecture. Metabolic profiling using liquid chromatography-mass spectrometry (LC-MS) analysis identified seventeen metabolites, including flavonoids, phenolics, fatty acids, terpenoids, phenylbutenoid dimers, amino acids, and saccharides. Eight metabolic compounds were reported in this study for the first time in quinoa. Some metabolites were detected as differentially expressed. The compound (Z)-1-(2,4,5-trimethoxyphenyl) butadiene and chrysin were found only in SPrecm. Sodium ((2R,3S,4R,5R)-5-(6-amino-9H-purin-9-yl)-3,4-dihydroxtetrahydrofuran-2-yl) methyl hydrogen phosphate and elenolic acid were detected only in CHEN-33, and quercetin, 3-hydroxyphloretin-3'-C-glucoside, kurarinone, and rosmarinic acid were identified only in D-12175. Variable importance in projection (VIP) scores annotated ten metabolites contributing to variability. Mineral analysis using atomic absorption spectrophotometry indicated that the quantity of magnesium and calcium is high in D-12175. In comparison, SPrecm showed a high quantity of magnesium compared to CHEN-33, while CHEN-33 showed a high quantity of calcium compared to SPrecm. However, the proximate composition showed no significant difference among quinoa accessions. Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-023-01398-2.

3.
Mol Biol Rep ; 49(12): 11675-11684, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36178561

RESUMEN

BACKGROUND: Disease-resistant cultivars are the best solution to get their maximum yield potential and avoid fungicide application. There is no doubt about the contribution, and use of R genes (resistance genes) in resistance development in plants, while S genes (susceptibility genes) also hold a strong position in pathogenesis by resistance repression, and their loss of function contributes to enhanced resistance. Hence, we attempted to knock out the function of the StERF3 gene in potatoes through CRISPR/Cas9-based genome editing and investigated the CRISPR/Cas9 approach as strategic control against late blight disease in potato plants. METHODS AND RESULTS: The StERF3 gene was edited in late blight susceptible cv. Lady Rosetta. Full allelic edited plants were identified through DnpI, and N1aIV mediated restriction digestion and then further analyzed through Indel Detection by Amplicon Analysis. Sequence analysis of targeted plants for indel identification showed full allelic editing. The detached leaf assay of full allelic edited plants demonstrated the role of the StERF3 gene in susceptibility to late blight in potatoes. In planta disease assay also showed reduced, slowed, and delayed disease progression in StERF3-loss-of-function mutants compared to wild-type (control) plants. Less fungal biomass was quantified in knockouts through Real-time qPCR that supported less susceptibility of edited plants to late blight. Besides, relatively high expression of pathogens-related genes, StPR1, and StNPR1, were also observed in StERF3-loss-of-function mutants compared to the corresponding control. CONCLUSION: The results showed the functional inhibition of StERF3 genes using the CRISPR/Cas9 approach. The functional knockouts (StERF3 gene-edited potato plants) revealed enhanced resistance against Phytophthora infestans, thereby demonstrating the best strategic control for late blight disease in potato plants.


Asunto(s)
Phytophthora infestans , Solanum tuberosum , Humanos , Solanum tuberosum/genética , Sistemas CRISPR-Cas/genética , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Phytophthora infestans/genética , Genes de Plantas , Resistencia a la Enfermedad/genética
4.
Clin Exp Hypertens ; 44(6): 557-566, 2022 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-35635242

RESUMEN

BACKGROUND: Phytolaccagenin, a natural triterpenoid, is reported for various biological activities that indicate its potential role in the management of hypertension. METHODS: Phytolaccagenin was evaluated for its antihypertensive activity in rat models via in vivo and in vitro experiments using polyethylene tubings for cannulation, organ bath bubbled with carbogen gas, and a pressure transducer connected to a PowerLab data acquisition system. RESULTS: Intravenous administration of phytolaccagenin decreased mean arterial pressure (MAP), significantly, in normotensive and hypertensive anesthetized rats. Pretreatment of rats with atropine (2 mg/kg) partially reversed the decrease in blood pressure due to phytolaccagenin at first tested doses. However, Nω-nitro-L-arginine methyl ester (L-NAME) (100 mg/kg) pretreatment modified the effect of phytolaccagenin on blood pressure with greater response. In isolated rat aortic rings precontracted with phenylephrine, cumulative addition of phytolaccagenin induced relaxation that is ablated (50%) with denudation and pre-incubation with atropine (1 µM) and L-NAME (10 µM). Phytolaccagenin also partially inhibited high K+ precontraction at initial doses, while an inhibitory effect was observed at higher concentrations, confirming its effect on voltage-dependent calcium channels. In isolated spontaneously beating rat atrial strips, phytolaccagenin suppressed the atrial tone that was reduced with isoprenaline and atropine pre-incubation, suggesting the role of cardiac adrenergic and muscarinic receptors. Interestingly, atenolol (1 µM) pretreatment also ablated the cardiac effects of phytolaccagenin. CONCLUSION: The antihypertensive effect of phytolaccagenin is due to a decrease in vascular resistance and cardiac depressant effects. These effects are mediated via muscarinic receptors-linked NO pathway, inhibitory effect on Ca2+ movements (vascular), and activation of cardiac muscarinic and blockade of ß-adrenergic receptors.


Asunto(s)
Antihipertensivos , Hipertensión , Animales , Antihipertensivos/farmacología , Antihipertensivos/uso terapéutico , Derivados de Atropina/farmacología , Derivados de Atropina/uso terapéutico , Presión Sanguínea , Endotelio Vascular , Hipertensión/tratamiento farmacológico , NG-Nitroarginina Metil Éster/farmacología , Óxido Nítrico/metabolismo , Ratas , Ratas Sprague-Dawley , Receptores Muscarínicos/uso terapéutico , Vasodilatación
5.
BMC Med Inform Decis Mak ; 22(1): 90, 2022 04 04.
Artículo en Inglés | MEDLINE | ID: mdl-35379228

RESUMEN

BACKGROUND: The digital pathology images obtain the essential information about the patient's disease, and the automated nuclei segmentation results can help doctors make better decisions about diagnosing the disease. With the speedy advancement of convolutional neural networks in image processing, deep learning has been shown to play a significant role in the various analysis of medical images, such as nuclei segmentation, mitosis detection and segmentation etc. Recently, several U-net based methods have been developed to solve the automated nuclei segmentation problems. However, these methods fail to deal with the weak features representation from the initial layers and introduce the noise into the decoder path. In this paper, we propose a multiscale attention learning network (MSAL-Net), where the dense dilated convolutions block captures more comprehensive nuclei context information, and a newly modified decoder part is introduced, which integrates with efficient channel attention and boundary refinement modules to effectively learn spatial information for better prediction and further refine the nuclei cell of boundaries. RESULTS: Both qualitative and quantitative results are obtained on the publicly available MoNuseg dataset. Extensive experiment results verify that our proposed method significantly outperforms state-of-the-art methods as well as the vanilla Unet method in the segmentation task. Furthermore, we visually demonstrate the effect of our modified decoder part. CONCLUSION: The MSAL-Net shows superiority with a novel decoder to segment the touching and blurred background nuclei cells obtained from histopathology images with better performance for accurate decoding.


Asunto(s)
Procesamiento de Imagen Asistido por Computador , Redes Neurales de la Computación , Atención , Humanos , Procesamiento de Imagen Asistido por Computador/métodos
6.
Bioorg Med Chem Lett ; 41: 127973, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-33753261

RESUMEN

α1-antitrypsin deficiency is characterised by the misfolding and intracellular polymerisation of mutant α1-antitrypsin protein within the endoplasmic reticulum (ER) of hepatocytes. Small molecules that bind and stabilise Z α1-antitrypsin were identified via a DNA-encoded library screen. A subsequent structure based optimisation led to a series of highly potent, selective and cellular active α1-antitrypsin correctors.


Asunto(s)
Diseño de Fármacos , Pliegue de Proteína , alfa 1-Antitripsina/metabolismo , Cristalización , Desarrollo de Medicamentos/métodos , Evaluación Preclínica de Medicamentos , Retículo Endoplásmico/metabolismo , Biblioteca de Genes , Hepatocitos/metabolismo , Humanos , Modelos Moleculares , Conformación Proteica , alfa 1-Antitripsina/genética
7.
Clin Exp Hypertens ; 43(8): 723-729, 2021 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-34396877

RESUMEN

Background/objectives: Steroidal saponins are widely distributed in medicinal plants with potential applications in cardiovascular disorders. Gitogenin, a saponin, has not been explored as antihypertensive; this investigation was aimed to explore its blood pressure lowering potential and underlying mechanisms.Methodology: The effect of gitogenin was evaluated on blood pressure in vivo, using normotensive rat model and the underlying cardiovascular mechanism(s) in vitro, in isolated rat aorta and in atria preparations using PowerLab data acquisition system (ADInstrument, Australia).Results: Intravenous injection of gitogenin decreased mean arterial pressure (MAP) in anesthetized rats. Atropine (1 mg/kg) and L-NAME (100 mg/kg) pretreatment significantly (*p < .05) attenuated effect on MAP to gitogenin. In isolated intact aortic rings, gitogenin induced endothelium-dependent vasodilatation (maximum 65%), which was ablated (maximum 22%) with L-NAME (100 mg/kg) and atropine (1 µM) pretreatment or endothelium removal. Gitogenin was found more potent against angiotensin II precontractions without effect on high K+ and low K+ precontractions. In isolated rat right atria, gitogenin suppressed rate and force of contractions. Atropine (1 µM) pretreatment partially inhibited effect of gitogenin on force and eliminated its effect on rate. Combined atropine (10 µM) and atenolol (0.5 µM) pretreatment was without effect on force of contractions but eliminated effect of gitogenin on rate with 25% increase.Conclusion: These findings indicate that antihypertensive effect of gitogenin is the outcome of vascular and cardiac effects; agonistic effect on vascular M3 and cardiac M2 receptors; and being more selective for M2. Increase in the rate of atrial contraction might be of clinical importance.


Asunto(s)
Hipertensión , Saponinas , Animales , Aorta Torácica , Presión Sanguínea , Endotelio Vascular , Hipertensión/tratamiento farmacológico , Ratas , Ratas Sprague-Dawley , Saponinas/farmacología , Espirostanos , Vasodilatación
8.
Orbit ; 39(1): 53-60, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30821588

RESUMEN

This case report deals with two patients with lacrimal sac swellings. Case 1 presented with bilateral sac swelling and Case 2 with a unilateral presentation. Dacrocystorhinostomy (DCR) followed by biopsies of both sacs in Case 1 revealed inflammatory polyps of the sac mucosa, identical in appearance to typical nasal allergic inflammatory polyps. The biopsies were accompanied by typical allergic mucin, featuring tiered mucin layers between which were numerous eosinophils, accompanied by Charcot-Leyden crystals. The histology of the dacryocystectomy specimen for Case 2 showed identical histopathological changes with the additional feature of prominent numbers of Immunoglobulin G (IgG)4-positive plasma cells in the stroma of the lacrimal sac inflammatory polyps. These features extend the sites affected by allergic inflammatory polyps and allergic mucin and possible pathogenesis is discussed.


Asunto(s)
Dacriocistorrinostomía/métodos , Aparato Lagrimal/patología , Micosis/diagnóstico por imagen , Pólipos Nasales/cirugía , Conducto Nasolagrimal/patología , Anciano , Biopsia con Aguja , Estudios de Seguimiento , Humanos , Hipersensibilidad/inmunología , Hipersensibilidad/fisiopatología , Inmunohistoquímica , Aparato Lagrimal/diagnóstico por imagen , Aparato Lagrimal/cirugía , Masculino , Persona de Mediana Edad , Mucinas/metabolismo , Micosis/tratamiento farmacológico , Micosis/patología , Pólipos Nasales/diagnóstico por imagen , Pólipos Nasales/patología , Conducto Nasolagrimal/diagnóstico por imagen , Conducto Nasolagrimal/cirugía , Muestreo , Tomografía Computarizada por Rayos X/métodos , Resultado del Tratamiento
9.
Biochem J ; 473(19): 3269-90, 2016 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-27407165

RESUMEN

Serpins are important regulators of proteolytic pathways with an antiprotease activity that involves a conformational transition from a metastable to a hyperstable state. Certain mutations permit the transition to occur in the absence of a protease; when associated with an intermolecular interaction, this yields linear polymers of hyperstable serpin molecules, which accumulate at the site of synthesis. This is the basis of many pathologies termed the serpinopathies. We have previously identified a monoclonal antibody (mAb4B12) that, in single-chain form, blocks α1-antitrypsin (α1-AT) polymerisation in cells. Here, we describe the structural basis for this activity. The mAb4B12 epitope was found to encompass residues Glu32, Glu39 and His43 on helix A and Leu306 on helix I. This is not a region typically associated with the serpin mechanism of conformational change, and correspondingly the epitope was present in all tested structural forms of the protein. Antibody binding rendered ß-sheet A - on the opposite face of the molecule - more liable to adopt an 'open' state, mediated by changes distal to the breach region and proximal to helix F. The allosteric propagation of induced changes through the molecule was evidenced by an increased rate of peptide incorporation and destabilisation of a preformed serpin-enzyme complex following mAb4B12 binding. These data suggest that prematurely shifting the ß-sheet A equilibrium towards the 'open' state out of sequence with other changes suppresses polymer formation. This work identifies a region potentially exploitable for a rational design of ligands that is able to dynamically influence α1-AT polymerisation.


Asunto(s)
Serpinas/metabolismo , Regulación Alostérica , Anticuerpos Monoclonales/química , Espectroscopía de Resonancia por Spin del Electrón , Ensayo de Inmunoadsorción Enzimática , Transferencia Resonante de Energía de Fluorescencia , Mutagénesis Sitio-Dirigida , Polimerizacion , Temperatura , alfa 1-Antitripsina/química , alfa 1-Antitripsina/genética
10.
Am J Respir Cell Mol Biol ; 54(1): 71-80, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26091018

RESUMEN

Misfolding, polymerization, and defective secretion of functional alpha-1 antitrypsin underlies the predisposition to severe liver and lung disease in alpha-1 antitrypsin deficiency. We have identified a novel (Ala336Pro, Baghdad) deficiency variant and characterized it relative to the wild-type (M) and Glu342Lys (Z) alleles. The index case is a homozygous individual of consanguineous parentage, with levels of circulating alpha-1 antitrypsin in the moderate deficiency range, but is a biochemical phenotype that could not be classified by standard methods. The majority of the protein was present as functionally inactive polymer, and the remaining monomer was 37% active relative to the wild-type protein. These factors combined indicate an 85 to 95% functional deficiency, similar to that seen with ZZ homozygotes. Biochemical, biophysical, and computational studies further defined the molecular basis of this deficiency. These studies demonstrated that native Ala336Pro alpha-1 antitrypsin could populate the polymerogenic intermediate-and therefore polymerize-more readily than either wild-type alpha-1 antitrypsin or the Z variant. In contrast, folding was far less impaired in Ala336Pro alpha-1 antitrypsin than in the Z variant. The data are consistent with a disparate contribution by the "breach" region and "shutter" region of strand 5A to folding and polymerization mechanisms. Moreover, the findings demonstrate that, in these variants, folding efficiency does not correlate directly with the tendency to polymerize in vitro or in vivo. They therefore differentiate generalized misfolding from polymerization tendencies in missense variants of alpha-1 antitrypsin. Clinically, they further support the need to quantify loss-of-function in alpha-1 antitrypsin deficiency to individualize patient care.


Asunto(s)
Mutación , Deficiencia de alfa 1-Antitripsina/genética , alfa 1-Antitripsina/genética , Adulto , Análisis Mutacional de ADN , Estabilidad de Enzimas , Femenino , Predisposición Genética a la Enfermedad , Homocigoto , Humanos , Cinética , Modelos Moleculares , Fenotipo , Conformación Proteica , Desnaturalización Proteica , Pliegue de Proteína , Multimerización de Proteína , alfa 1-Antitripsina/química , alfa 1-Antitripsina/metabolismo , Deficiencia de alfa 1-Antitripsina/enzimología
11.
Hum Mol Genet ; 23(4): 929-41, 2014 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-24097797

RESUMEN

Overexpression of Z α1-antitrypsin is known to induce polymer formation, prime the cells for endoplasmic reticulum stress and initiate nuclear factor kappa B (NF-κB) signalling. However, whether endogenous expression in primary bronchial epithelial cells has similar consequences remains unclear. Moreover, the mechanism of NF-κB activation has not yet been elucidated. Here, we report excessive NF-κB signalling in resting primary bronchial epithelial cells from ZZ patients compared with wild-type (MM) controls, and this appears to be mediated by mitogen-activated protein/extracellular signal-regulated kinase, EGF receptor and ADAM17 activity. Moreover, we show that rather than being a response to protein polymers, NF-κB signalling in airway-derived cells represents a loss of anti-inflammatory signalling by M α1-antitrypsin. Treatment of ZZ primary bronchial epithelial cells with purified plasma M α1-antitrypsin attenuates this inflammatory response, opening up new therapeutic options to modulate airway inflammation in the lung.


Asunto(s)
Células Epiteliales/metabolismo , Sistema de Señalización de MAP Quinasas , Mutación Missense , Transducción de Señal , alfa 1-Antitripsina/genética , Proteínas ADAM/metabolismo , Proteína ADAM17 , Línea Celular Tumoral , Citocinas/metabolismo , Estrés del Retículo Endoplásmico , Receptores ErbB/metabolismo , Humanos , Mediadores de Inflamación/metabolismo , Pulmón/patología , FN-kappa B/metabolismo , Cultivo Primario de Células , Multimerización de Proteína , Procesamiento Proteico-Postraduccional , alfa 1-Antitripsina/biosíntesis
12.
FASEB J ; 29(6): 2667-78, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25757566

RESUMEN

Mutant Z α1-antitrypsin (E342K) accumulates as polymers within the endoplasmic reticulum (ER) of hepatocytes predisposing to liver disease, whereas low levels of circulating Z α1-antitrypsin lead to emphysema by loss of inhibition of neutrophil elastase. The ideal therapy should prevent polymer formation while preserving inhibitory activity. Here we used mAb technology to identify interactors with Z α1-antitrypsin that comply with both requirements. We report the generation of an mAb (4B12) that blocked α1-antitrypsin polymerization in vitro at a 1:1 molar ratio, causing a small increase of the stoichiometry of inhibition for neutrophil elastase. A single-chain variable fragment (scFv) intrabody was generated based on the sequence of mAb4B12. The expression of scFv4B12 within the ER (scFv4B12KDEL) and along the secretory pathway (scFv4B12) reduced the intracellular polymerization of Z α1-antitrypsin by 60%. The scFv4B12 intrabody also increased the secretion of Z α1-antitrypsin that retained inhibitory activity against neutrophil elastase. MAb4B12 recognized a discontinuous epitope probably located in the region of helices A/C/G/H/I and seems to act by altering protein dynamics rather than binding preferentially to the native state. This novel approach could reveal new target sites for small-molecule intervention that may block the transition to aberrant polymers without compromising the inhibitory activity of Z α1-antitrypsin.


Asunto(s)
Polimerizacion/efectos de los fármacos , Inhibidores de Proteasas/metabolismo , Anticuerpos de Cadena Única/farmacología , alfa 1-Antitripsina/metabolismo , Animales , Secuencia de Bases , Células COS , Chlorocebus aethiops , Retículo Endoplásmico/metabolismo , Humanos , Immunoblotting , Espacio Intracelular/efectos de los fármacos , Espacio Intracelular/metabolismo , Cinética , Elastasa de Leucocito/metabolismo , Ratones Endogámicos BALB C , Datos de Secuencia Molecular , Mutación , Inhibidores de Proteasas/inmunología , Anticuerpos de Cadena Única/genética , Anticuerpos de Cadena Única/metabolismo , alfa 1-Antitripsina/genética , alfa 1-Antitripsina/inmunología
13.
Biochem J ; 468(1): 99-108, 2015 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-25738741

RESUMEN

A monoclonal antibody (mAb) that binds to a transient intermediate may act as a catalyst for the corresponding reaction; here we show this principle can extend on a macro molecular scale to the induction of mutant-like oligomerization in a wild-type protein. Using the common pathogenic E342K (Z) variant of α1-antitrypsin as antigen-whose native state is susceptible to the formation of a proto-oligomeric intermediate-we have produced a mAb (5E3) that increases the rate of oligomerization of the wild-type (M) variant. Employing ELISA, gel shift, thermal stability and FRET time-course experiments, we show that mAb5E3 does not bind to the native state of α1-antitrypsin, but recognizes a cryptic epitope in the vicinity of the post-helix A loop and strand 4C that is revealed upon transition to the polymerization intermediate, and which persists in the ensuing oligomer. This epitope is not shared by loop-inserted monomeric conformations. We show the increased amenity to polymerization by either the pathogenic E342K mutation or the binding of mAb5E3 occurs without affecting the energetic barrier to polymerization. As mAb5E3 also does not alter the relative stability of the monomer to intermediate, it acts in a manner similar to the E342K mutant, by facilitating the conformational interchange between these two states.


Asunto(s)
Anticuerpos Monoclonales de Origen Murino/inmunología , alfa 1-Antitripsina/genética , alfa 1-Antitripsina/inmunología , Sustitución de Aminoácidos , Animales , Anticuerpos Monoclonales de Origen Murino/química , Especificidad de Anticuerpos , Epítopos/química , Epítopos/genética , Variación Genética , Humanos , Fragmentos Fab de Inmunoglobulinas/química , Fragmentos Fab de Inmunoglobulinas/inmunología , Ratones , Ratones Endogámicos BALB C , Modelos Moleculares , Mutación , Conformación Proteica , Multimerización de Proteína/inmunología , Estabilidad Proteica , Estructura Cuaternaria de Proteína , Termodinámica , alfa 1-Antitripsina/química
14.
Hum Mol Genet ; 22(22): 4616-26, 2013 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-23814041

RESUMEN

Mutants of neuroserpin are retained as polymers within the endoplasmic reticulum (ER) of neurones to cause the autosomal dominant dementia familial encephalopathy with neuroserpin inclusion bodies or FENIB. The cellular consequences are unusual in that the ordered polymers activate the ER overload response (EOR) in the absence of the canonical unfolded protein response. We use both cell lines and Drosophila models to show that the G392E mutant of neuroserpin that forms polymers is degraded by UBE2j1 E2 ligase and Hrd1 E3 ligase while truncated neuroserpin, a protein that lacks 132 amino acids, is degraded by UBE2g2 (E2) and gp78 (E3) ligases. The degradation of G392E neuroserpin results from SREBP-dependent activation of the cholesterol biosynthetic pathway in cells that express polymers of neuroserpin (G392E). Inhibition of HMGCoA reductase, the limiting enzyme of the cholesterol biosynthetic pathway, reduced the ubiquitination of G392E neuroserpin in our cell lines and increased the retention of neuroserpin polymers in both HeLa cells and primary neurones. Our data reveal a reciprocal relationship between cholesterol biosynthesis and the clearance of mutant neuroserpin. This represents the first description of a link between sterol metabolism and modulation of the proteotoxicity mediated by the EOR.


Asunto(s)
Colesterol/biosíntesis , Drosophila melanogaster/metabolismo , Epilepsias Mioclónicas/metabolismo , Trastornos Heredodegenerativos del Sistema Nervioso/metabolismo , Neuropéptidos/metabolismo , Polímeros/metabolismo , Serpinas/metabolismo , Animales , Células Cultivadas , Modelos Animales de Enfermedad , Drosophila melanogaster/genética , Retículo Endoplásmico/genética , Retículo Endoplásmico/metabolismo , Epilepsias Mioclónicas/genética , Epilepsias Mioclónicas/patología , Células HeLa , Trastornos Heredodegenerativos del Sistema Nervioso/genética , Trastornos Heredodegenerativos del Sistema Nervioso/patología , Humanos , Ratones , Proteínas Mutantes/metabolismo , Neuronas/metabolismo , Neuropéptidos/genética , Desplegamiento Proteico , Serpinas/genética , Transducción de Señal , Enzimas Ubiquitina-Conjugadoras/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Respuesta de Proteína Desplegada , Neuroserpina
15.
Biochem J ; 460(1): 103-15, 2014 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-24552432

RESUMEN

Serpins are protease inhibitors whose most stable state is achieved upon transition of a central 5-stranded ß-sheet to a 6-stranded form. Mutations, low pH, denaturants and elevated temperatures promote this transition, which can result in a growing polymer chain of inactive molecules. Different types of polymer are possible, but, experimentally only heat has been shown to generate polymers in vitro consistent with ex vivo pathological specimens. Many mutations that alter the rate of heat-induced polymerization have been described, but interpretation is problematic because discrimination is lacking between the effect of global changes in native stability and specific effects on structural mechanism. We show that the temperature midpoint (Tm) of thermal denaturation reflects the transition of α1-antitrypsin to the polymerization intermediate, and determine the relationship with fixed-temperature polymerization half-times (t0.5) in the presence of stabilizing additives [TMAO (trimethylamine N-oxide), sucrose and sodium sulfate], point mutations and disulfide bonds. Combined with a retrospective analysis of 31 mutants characterized in the literature, the results of the present study show that global changes to native state stability are the predominant basis for the effects of mutations and osmolytes on heat-induced polymerization, summarized by the equation: ln(t0.5,mutant/t0.5,wild-type)=0.34×ΔTm. It is deviations from this relationship that hold key information about the polymerization process.


Asunto(s)
Quimotripsina/química , Quimotripsina/genética , Mutación Puntual/genética , Polimerizacion , alfa 1-Antitripsina/química , alfa 1-Antitripsina/genética , Sustitución de Aminoácidos/genética , Animales , Bovinos , Quimotripsina/metabolismo , Dicroismo Circular , Estabilidad Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Estudios Retrospectivos , Temperatura , alfa 1-Antitripsina/metabolismo
16.
Acta Neurochir (Wien) ; 156(5): 989-98; discussion 998, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24615066

RESUMEN

BACKGROUND: Titanium cranioplasty (TC) has been associated with high complication rates, but abundant data are lacking. We aimed to determine the incidence and type of complications following TC and risk factors for complications. METHODS: A retrospective review was performed on 174 patients who underwent TC at two London units over a seven year period. Data were collected on demographics, primary pathology, perioperative details, complications and functional outcome. Skull defect size was estimated using 3-dimensional computed tomographic reconstructions. RESULTS: The overall complication rate was 26.4 % (46/174), and plate removal rate10.3 % (18/174). The commonest complication was infection, which accounted for 69 % of plate removals. Patients who had undergone craniectomy for trauma had a higher complication rate (35 vs 21 %; p = 0.043) and plate removal rate (16 vs 7 %; p = 0.049) than others. There was a non-significant trend towards the association of craniectomy-to-cranioplasty interval of 4-8 months with the lowest complication rate and shortest postoperative hospital stay. Patients with a skull defect larger than 100 cm(2) had the highest complication rate (p < 0.001), highest plate removal rate (p = 0.039), and longest postoperative hospital stay (p = 0.019). Bifrontal versus unilateral cranioplasty was associated with a significantly higher complication rate (40 vs 14 %) and length of hospital stay (5.0 vs 2.9 days). There was no perioperative mortality and no change between pre-operative and post-operative functional outcome. CONCLUSION: In the largest UK study on cranioplasty to date, we have demonstrated that size of defect, traumatic aetiology and bifrontal insertion are risk factors for complications. Our results suggest that the timing of cranioplasty may be important with late (> 12 months) TC associated with a higher rate of complications, although further prospective studies on the optimal timing of TC are required to establish the observed trend. Our data can help clinicians stratify risk to inform the consent process and aid pre-operative planning.


Asunto(s)
Placas Óseas , Traumatismos Craneocerebrales/cirugía , Craniectomía Descompresiva , Hematoma Subdural Agudo/cirugía , Neoplasias Meníngeas/cirugía , Meningioma/cirugía , Procedimientos de Cirugía Plástica , Complicaciones Posoperatorias , Titanio , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Periodo Posoperatorio , Falla de Prótesis , Reoperación , Estudios Retrospectivos , Factores de Riesgo , Tomografía Computarizada por Rayos X/efectos adversos , Adulto Joven
17.
Front Microbiol ; 15: 1349239, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38562468

RESUMEN

Chenopodium quinoa manifests adaptability to grow under varying agro-climatic scenarios. Assessing quinoa germplasm's phenotypic and genetic variability is a prerequisite for introducing it as a potential candidate in cropping systems. Adaptability is the basic outcome of ecological genomics of crop plants. Adaptive variation predicted with a genome-wide association study provides a valuable basis for marker-assisted breeding. Hence, a panel of 72 quinoa plants was phenotyped for agro morphological attributes and association-mapping for distinct imperative agronomic traits. Inter simple sequence repeat (ISSR) markers were employed to assess genetic relatedness and population structure. Heatmap analysis showed three genotypes were early maturing, and six genotypes were attributed for highest yield. The SD-121-07 exhibited highest yield per plant possessing green, glomerulate shaped, compact density panicle with less leaves. However, SJrecm-03 yielded less exhibiting pink, intermediate shape, intermediate density panicles with less leaves. The phenotyping revealed strong correlation of panicle architecture with yield in quinoa. A genome-wide association study unraveled the associations between ISSR makers and agro-morphological traits. Mixed linear modes analysis yielded nine markers associated with eight traits at p ≤ 0.01. Moreover, ISSR markers significantly associated with panicle shape and leafiness were also associated with yield per plant. These findings contribute to the provision of authenticity for marker-assisted selection that ultimately would support quinoa breeding programs.

18.
Thorax ; 68(7): 670-6, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22744884

RESUMEN

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a multicomponent condition that is characterised by airflow obstruction that is not fully reversible and is a major global cause of morbidity and mortality. The most widely used marker of disease severity and progression is FEV1. However, FEV1 correlates poorly with both symptoms and other measures of disease progression and thus there is an urgent need for other biological markers to better characterise individuals with COPD. Fibrinogen is an acute phase plasma protein that has emerged as a promising biomarker in COPD. Here we review the current clinical evidence linking fibrinogen with COPD and its associated co-morbidities and discuss its potential utility as a biomarker. METHODS: Searches for appropriate studies were undertaken on PubMed using search terms fibrinogen, COPD, emphysema, chronic bronchitis, FEV1, cardiovascular disease, exacerbation and mortality. RESULTS: There is strong evidence of an association between fibrinogen and the presence of COPD, the presence and frequency of exacerbations and with mortality. Fibrinogen is associated with disease severity but does not predict lung function decline, a measure used as a surrogate for disease activity. The role of fibrinogen in identifying inflammatory co morbidities, particularly cardiovascular disease, remains unclear. Fibrinogen is reduced by p38 mitogen-activated protein kinase inhibitors in individuals with stable disease and by oral corticosteroids during exacerbations. CONCLUSIONS: Fibrinogen is likely to be a useful biomarker to stratify individuals with COPD into those with a high or low risk of future exacerbations and may identify those with a higher risk of mortality.


Asunto(s)
Biomarcadores/sangre , Fibrinógeno/análisis , Enfermedad Pulmonar Obstructiva Crónica/sangre , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Progresión de la Enfermedad , Humanos , Índice de Severidad de la Enfermedad
20.
Front Genet ; 14: 1136688, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36999059

RESUMEN

Dalbergia sissoo is one of the most economically important trees in forestry, agroforestry, and horticulture. This tree species is severely threatened by dieback. Widespread dieback outbreaks and infestations have drastically destroyed billions of D. sissoo trees. Hence, we attempted to resolve the dieback etiology through phylogenomics associated with D. sissoo mortality. The Ceratocystis species was evaluated using morphologically investigated fungal isolates collected from dieback-affected tissue plants. Based on the symptomatology, we have differentiated dieback from Fusarium wilt and concluded that the Ceratocystis fimbriata sensu lato complex is causing shisham dieback in Pakistan. As the Ceratocystis species complex is a cryptic species complex, we used genomics and phylogenetic analysis for deciphering its evolutionary hierarchical order. The pathogen's operational taxonomy was unlocked with the help of phylogenomics, and it was discovered that isolates from D. sissoo represent a species distinct from the other species in the C. fimbriata sensu lato species complex. The name Ceratocystis dalbergicans sp. nov. has been given to the fungus causing dieback disease in D. sissoo.

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