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1.
Proc Natl Acad Sci U S A ; 114(24): 6310-6315, 2017 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-28559344

RESUMEN

Regulation of mRNA translation is a major control point for gene expression and is critical for life. Of central importance is the complex between cap-bound eukaryotic initiation factor 4E (eIF4E), eIF4G, and poly(A) tail-binding protein (PABP) that circularizes mRNAs, promoting translation and stability. This complex is often targeted to regulate overall translation rates, and also by mRNA-specific translational repressors. However, the mechanisms of mRNA-specific translational activation by RNA-binding proteins remain poorly understood. Here, we address this deficit, focusing on a herpes simplex virus-1 protein, ICP27. We reveal a direct interaction with PABP that is sufficient to promote PABP recruitment and necessary for ICP27-mediated activation. PABP binds several translation factors but is primarily considered to activate translation initiation as part of the PABP-eIF4G-eIF4E complex that stimulates the initial cap-binding step. Importantly, we find that ICP27-PABP forms a complex with, and requires the activity of, eIF4G. Surprisingly, ICP27-PABP-eIF4G complexes act independently of the effects of PABP-eIF4G on cap binding to promote small ribosomal subunit recruitment. Moreover, we find that a cellular mRNA-specific regulator, Deleted in Azoospermia-like (Dazl), also employs the PABP-eIF4G interaction in a similar manner. We propose a mechanism whereby diverse RNA-binding proteins directly recruit PABP, in a non-poly(A) tail-dependent manner, to stimulate the small subunit recruitment step. This strategy may be particularly relevant to biological conditions associated with hypoadenylated mRNAs (e.g., germ cells/neurons) and/or limiting cytoplasmic PABP (e.g., viral infection, cell stress). This mechanism adds significant insight into our knowledge of mRNA-specific translational activation and the function of the PABP-eIF4G complex in translation initiation.


Asunto(s)
Factor 4G Eucariótico de Iniciación/metabolismo , Proteínas de Unión a Poli(A)/metabolismo , ARN Mensajero/metabolismo , Animales , Factor 4G Eucariótico de Iniciación/genética , Femenino , Proteínas Inmediatas-Precoces/genética , Proteínas Inmediatas-Precoces/metabolismo , Modelos Biológicos , Mutación , Oocitos/metabolismo , Iniciación de la Cadena Peptídica Traduccional , Proteínas de Unión a Poli(A)/genética , Unión Proteica , Caperuzas de ARN/genética , Caperuzas de ARN/metabolismo , ARN Mensajero/genética , ARN Viral/genética , ARN Viral/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Técnicas del Sistema de Dos Híbridos , Xenopus laevis
2.
Biomed Chromatogr ; 32(7): e4217, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29601646

RESUMEN

Enantioselective analysis of (RS)-fexofenadine was carried out by achiral HPLC via a derivatization approach using N-hydroxy-benzotriazolyl-(S)-naproxen ester (synthesized for this purpose) and three chirally pure amines as chiral derivatizing reagents. There occurred formation of amide and anhydride types of diastereomeric derivatives. These were separated and isolated by HPLC (analytical and preparative). The structures and configurations were verified via recording full-scan product ion mass spectra using LC-MS, 1 HNMR spectra, Chem3D Pro 12.0 software and the software Gaussian 09 Rev.A.02 program and hybrid density functional B3LYP with 6-31G basis set supplemented with polarimetry. Experimental conditions for synthesis and separations were optimized and the elution order was established. Analytical separation was performed on a C18 analytical column with different ratios of MeCN-TEAP buffer and MeOH-TEAP buffer (v/v) adjusted to pH 7.5 as mobile phase at a flow rate of 0.7 mL min-1 . Detection was performed via UV absorbance at 225 nm. The method was validated in accordance with International Conference on Harmonization guidelines. The detection limits were 6.25 and 7.87 ng mL-1 for first and second eluting diastereomeric derivatives, respectively.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Espectrometría de Masas/métodos , Terfenadina/análogos & derivados , Límite de Detección , Modelos Lineales , Reproducibilidad de los Resultados , Estereoisomerismo , Terfenadina/análisis , Terfenadina/química , Terfenadina/aislamiento & purificación
3.
Cochrane Database Syst Rev ; 10: CD012330, 2017 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-28972652

RESUMEN

BACKGROUND: Asthma is a chronic inflammatory disease that affects the airways and is common in both adults and children. It is characterised by symptoms including wheeze, shortness of breath, chest tightness, and cough. People with asthma may be helped to manage their condition through shared decision-making (SDM). SDM involves at least two participants (the medical practitioner and the patient) and mutual sharing of information, including the patient's values and preferences, to build consensus about favoured treatment that culminates in an agreed action. Effective self-management is particularly important for people with asthma, and SDM may improve clinical outcomes and quality of life by educating patients and empowering them to be actively involved in their own health. OBJECTIVES: To assess benefits and potential harms of shared decision-making for adults and children with asthma. SEARCH METHODS: We searched the Cochrane Airways Trials Register, which contains studies identified in several sources including CENTRAL, MEDLINE, and Embase. We also searched clinical trials registries and checked the reference lists of included studies. We conducted the most recent searches on 29 November 2016. SELECTION CRITERIA: We included studies of individual or cluster parallel randomised controlled design conducted to compare an SDM intervention for adults and children with asthma versus a control intervention. We included studies available as full-text reports, those published as abstracts only, and unpublished data, and we placed no restrictions on place, date, or language of publication. We included interventions targeting healthcare professionals or patients, their families or care-givers, or both. We included studies that compared the intervention versus usual care or a minimal control intervention, and those that compared an SDM intervention against another active intervention. We excluded studies of interventions that involved multiple components other than the SDM intervention unless the control group also received these interventions. DATA COLLECTION AND ANALYSIS: Two review authors independently screened searches, extracted data from included studies, and assessed risk of bias. Primary outcomes were asthma-related quality of life, patient/parent satisfaction, and medication adherence. Secondary outcomes included exacerbations of asthma, asthma control, acceptability/feasibility from the perspective of healthcare professionals, and all adverse events. We graded and presented evidence in a 'Summary of findings' table.We were unable to pool any of the extracted outcome data owing to clinical and methodological heterogeneity but presented findings in forest plots when possible. We narratively described skewed data. MAIN RESULTS: We included four studies that compared SDM versus control and included a total of 1342 participants. Three studies recruited children with asthma and their care-givers, and one recruited adults with asthma. Three studies took place in the United States, and one in the Netherlands. Trial duration was between 6 and 24 months. One trial delivered the SDM intervention to the medical practitioner, and three trials delivered the SDM intervention directly to the participant. Two paediatric studies involved use of an online portal, followed by face-to-face consultations. One study delivered an SDM intervention or a clinical decision-making intervention through a mixture of face-to-face consultations and telephone calls. The final study randomised paediatric general practice physicians to receive a seminar programme promoting application of SDM principles. All trials were open-label, although one study, which delivered the intervention to physicians, stated that participants were unaware of their physicians' involvement in the trial. We had concerns about selection and attrition bias and selective reporting, and we noted that one study substantially under-recruited participants. The four included studies used different approaches to measure fidelity/intervention adherence and to report study findings.One study involving adults with poorly controlled asthma reported improved quality of life (QOL) for the SDM group compared with the control group, using the Asthma Quality of Life Questionnaire (AQLQ) for assessment (mean difference (MD) 1.90, 95% confidence interval (CI) 1.24 to 2.91), but two other trials did not identify a benefit. Patient/parent satisfaction with the performance of paediatricians was greater in the SDM group in one trial involving children. Medication adherence was better in the SDM group in two studies - one involving adults and one involving children (all medication adherence: MD 0.21, 95% CI 0.11 to 0.31; mean number of controlled medication prescriptions over 26 weeks: 1.1 in the SDM group (n = 26) and 0.7 in the control group (n = 27)). In one study, asthma-related visit rates were lower in the SDM group than in the usual care group (1.0/y vs 1.4/y; P = 0.016), but two other studies did not report a difference in exacerbations nor in prescriptions for short courses of oral steroids. Finally, one study described better odds of reporting no asthma problems in the SDM group than in the usual care group (odds ratio (OR) 1.90, 95% CI 1.26 to 2.87), although two other studies reporting asthma control did not identify a benefit with SDM. We found no information about acceptability of the intervention to the healthcare professional and no information on adverse events. Overall, our confidence in study results ranged from very low to moderate, and we downgraded outcomes owing to risk of bias, imprecision, and indirectness. AUTHORS' CONCLUSIONS: Substantial differences between the four included randomised controlled trials (RCTs) indicate that we cannot provide meaningful overall conclusions. Individual studies demonstrated some benefits of SDM over control, in terms of quality of life; patient and parent satisfaction; adherence to prescribed medication; reduction in asthma-related healthcare visits; and improved asthma control. Our confidence in the findings of these individual studies ranges from moderate to very low, and it is important to note that studies did not measure or report adverse events.Future trials should be adequately powered and of sufficient duration to detect differences in patient-important outcomes such as exacerbations and hospitalisations. Use of core asthma outcomes and validated scales when possible would facilitate future meta-analysis. Studies conducted in lower-income settings and including an economic evaluation would be of interest. Investigators should systematically record adverse events, even if none are anticipated. Studies identified to date have not included adolescents; future trials should consider their inclusion. Measuring and reporting of intervention fidelity is also recommended.


Asunto(s)
Asma/tratamiento farmacológico , Toma de Decisiones Clínicas , Toma de Decisiones , Participación del Paciente , Adulto , Niño , Progresión de la Enfermedad , Humanos , Cumplimiento de la Medicación , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto
4.
J Biol Chem ; 287(15): 12277-92, 2012 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-22334672

RESUMEN

The herpes simplex virus ICP27 protein is important for the expression and nuclear export of viral mRNAs. Although several binding sites have been mapped along the ICP27 sequence for various RNA and protein partners, including the transport receptor TAP of the host cell nuclear transport machinery, several aspects of ICP27 trafficking through the nuclear pore complex remain unclear. We investigated if ICP27 could interact directly with the nuclear pore complex itself, finding that ICP27 directly binds the core nucleoporin Nup62. This is confirmed through co-immunoprecipitation and in vitro binding assays with purified components. Mapping with ICP27 deletion and point mutants further shows that the interaction requires sequences in both the N and C termini of ICP27. Expression of wild type ICP27 protein inhibited both classical, importin α/ß-dependent and transportin-dependent nuclear import. In contrast, an ICP27 point mutant that does not interact with Nup62 had no such inhibitory effect. We suggest that ICP27 association with Nup62 provides additional binding sites at the nuclear pore for ICP27 shuttling, thus supporting ICP27-mediated transport. We propose that ICP27 competes with some host cell transport receptors for binding, resulting in inhibition of those host transport pathways.


Asunto(s)
Transporte Activo de Núcleo Celular , Herpesvirus Humano 1/fisiología , Interacciones Huésped-Patógeno , Proteínas Inmediatas-Precoces/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas de Complejo Poro Nuclear/metabolismo , Poro Nuclear/metabolismo , Sitios de Unión , Núcleo Celular/metabolismo , Núcleo Celular/virología , Células HeLa , Herpesvirus Humano 8/genética , Humanos , Proteínas Inmediatas-Precoces/genética , Inmunoprecipitación , Señales de Exportación Nuclear , Señales de Localización Nuclear , Poro Nuclear/virología , Proteínas de Transporte Nucleocitoplasmático/metabolismo , Mapeo Peptídico , Unión Proteica , Dominios y Motivos de Interacción de Proteínas , Estabilidad Proteica , ARN Mensajero/metabolismo , ARN Viral/metabolismo , Proteínas de Unión al ARN/metabolismo , Homología de Secuencia de Aminoácido
5.
Mol Cell Proteomics ; 10(1): M110.003129, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20876400

RESUMEN

Nuclear envelopes from liver and a neuroblastoma cell line have previously been analyzed by proteomics; however, most diseases associated with the nuclear envelope affect muscle. To determine whether muscle has unique nuclear envelope proteins, rat skeletal muscle nuclear envelopes were prepared and analyzed by multidimensional protein identification technology. Many novel muscle-specific proteins were identified that did not appear in previous nuclear envelope data sets. Nuclear envelope residence was confirmed for 11 of these by expression of fusion proteins and by antibody staining of muscle tissue cryosections. Moreover, transcript levels for several of the newly identified nuclear envelope transmembrane proteins increased during muscle differentiation using mouse and human in vitro model systems. Some of these proteins tracked with microtubules at the nuclear surface in interphase cells and accumulated at the base of the microtubule spindle in mitotic cells, suggesting they may associate with complexes that connect the nucleus to the cytoskeleton. The finding of tissue-specific proteins in the skeletal muscle nuclear envelope proteome argues the importance of analyzing nuclear envelopes from all tissues linked to disease and suggests that general investigation of tissue differences in organellar proteomes might yield critical insights.


Asunto(s)
Citoesqueleto/metabolismo , Proteínas de la Membrana/metabolismo , Músculo Esquelético/metabolismo , Membrana Nuclear/metabolismo , Proteínas Nucleares/metabolismo , Animales , Diferenciación Celular , Fraccionamiento Celular , Línea Celular , Humanos , Espectrometría de Masas , Proteínas de la Membrana/química , Ratones , Músculo Esquelético/citología , Músculo Esquelético/ultraestructura , Membrana Nuclear/ultraestructura , Proteínas Nucleares/química , Análisis de Secuencia por Matrices de Oligonucleótidos , Especificidad de Órganos , Ratas , Ratas Sprague-Dawley , Reproducibilidad de los Resultados
6.
Mol Cell Proteomics ; 9(12): 2571-85, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20693407

RESUMEN

A favored hypothesis to explain the pathology underlying nuclear envelopathies is that mutations in nuclear envelope proteins alter genome/chromatin organization and thus gene expression. To identify nuclear envelope proteins that play roles in genome organization, we analyzed nuclear envelopes from resting and phytohemagglutinin-activated leukocytes because leukocytes have a particularly high density of peripheral chromatin that undergoes significant reorganization upon such activation. Thus, nuclear envelopes were isolated from leukocytes in the two states and analyzed by multidimensional protein identification technology using an approach that used expected contaminating membranes as subtractive fractions. A total of 3351 proteins were identified between both nuclear envelope data sets among which were 87 putative nuclear envelope transmembrane proteins (NETs) that were not identified in a previous proteomics analysis of liver nuclear envelopes. Nuclear envelope localization was confirmed for 11 new NETs using tagged fusion proteins and antibodies on spleen cryosections. 27% of the new proteins identified were unique to one or the other of the two leukocyte states. Differences in expression between activated and resting leukocytes were confirmed for some NETs by RT-PCR, and most of these proteins appear to only be expressed in certain types of blood cells. Several known proteins identified in both data sets have functions in chromatin organization and gene regulation. To test whether the novel NETs identified might include those that also regulate chromatin, nine were run through two screens for different chromatin effects. One screen found two NETs that can recruit a specific gene locus to the nuclear periphery, and the second found a different NET that promotes chromatin condensation. The variation in the protein milieu with pharmacological activation of the same cell population and consequences for gene regulation suggest that the nuclear envelope is a complex regulatory system with significant influences on genome organization.


Asunto(s)
Genoma Humano , Leucocitos/metabolismo , Proteínas de la Membrana/metabolismo , Membrana Nuclear/metabolismo , Proteoma , Animales , Western Blotting , Línea Celular , Humanos , Microscopía Fluorescente , Ratas
7.
Mater Today Proc ; 51: 571-575, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35155130

RESUMEN

Many organizations are rapidly changing their procedures due to the rapid spread of corona virus (COVID-19) worldwide. Several companies have switched their entire workforce to temporary telecommuting and remote work. Like other employee-characters, there is believed to be a change in employee engagement as well. This research seeks to examine and statistically assess factors that can impact the employee engagement level. We collected data from 208 employees who are working from home in India with online questionnaire. Engagement scores have been calculated using UWES-14 (Utrecht Work Engagement Scale). We examined the impact of total 10 variables using multiple regression analysis. Our regression results suggest that proper virtual tools, contact by the organization leaders, mental health checkup and virtual training increases the employee engagement. Female employees are found to be more engaged than male employees while working from home. The number of kids are found to have negative impact on employee engagement. This implies that if the number of kids increases, the virtual employee engagement decreases. Our results could not find any significant impact of virtual teamwork, marital status, and entertainment tools on employee engagement. Based on the research results, this study make few recommendations. First, organizations should facilitate the improvement of virtual tools such as internet speed and personal computer configuration. Second, the salary employees should not be decreased. Third, the top organization leaders should have frequent contact with the employees, increase virtual training, and should encourage the employees to undergo the regular mental health checkup.

8.
Cell Mol Life Sci ; 67(8): 1353-69, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20091084

RESUMEN

Nuclear envelope complexity is expanding with respect to identification of protein components. Here we test the validity of proteomics results that identified 67 novel predicted nuclear envelope transmembrane proteins (NETs) from liver by directly comparing 30 as tagged fusions using targeting assays. This confirmed 21 as NETs, but 4 only targeted in certain cell types, underscoring the complexity of interactions that tether NETs to the nuclear envelope. Four NETs accumulated at the nuclear rim in normal fibroblasts but not in fibroblasts lacking lamin A, suggesting involvement of lamin A in tethering them in the nucleus. However, intriguingly, for the NETs tested alternative mechanisms for nuclear envelope retention could be found in Jurkat cells that normally lack lamin A. This study expands by a factor of three the number of liver NETs analyzed, bringing the total confirmed to 31, and shows that several have multiple mechanisms for nuclear envelope retention.


Asunto(s)
Lamina Tipo A/fisiología , Proteínas de la Membrana/metabolismo , Membrana Nuclear/metabolismo , Proteínas Nucleares/metabolismo , Animales , Western Blotting , Núcleo Celular/metabolismo , Células Cultivadas , Fibroblastos/citología , Fibroblastos/metabolismo , Hepatocitos/citología , Hepatocitos/metabolismo , Humanos , Riñón/citología , Riñón/metabolismo , Ratones , Ratones Noqueados , Mioblastos/citología , Mioblastos/metabolismo , Transporte de Proteínas , Proteómica , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
9.
iScience ; 24(9): 103055, 2021 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-34541469

RESUMEN

STimulator of INterferon Genes (STING) is an adaptor for cytoplasmic DNA sensing by cGAMP/cGAS that helps trigger innate immune responses (IIRs). Although STING is mostly localized in the ER, we find a separate inner nuclear membrane pool of STING that increases mobility and redistributes to the outer nuclear membrane upon IIR stimulation by transfected dsDNA or dsRNA mimic poly(I:C). Immunoprecipitation of STING from isolated nuclear envelopes coupled with mass spectrometry revealed a distinct nuclear envelope-STING proteome consisting of known nuclear membrane proteins and enriched in DNA- and RNA-binding proteins. Seventeen of these nuclear envelope STING partners are known to bind direct interactors of IRF3/7 transcription factors, and testing a subset of these revealed STING partners SYNCRIP, MEN1, DDX5, snRNP70, RPS27a, and AATF as novel modulators of dsDNA-triggered IIRs. Moreover, we find that SYNCRIP is a novel antagonist of the RNA virus, influenza A, potentially shedding light on reports of STING inhibition of RNA viruses.

10.
Biochem Soc Trans ; 38(Pt 1): 268-72, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20074072

RESUMEN

The nuclear periphery is a specialized environment in the nucleus that contributes to genome organization and correspondingly to gene regulation. Mammalian chromosomes and certain genes occupy defined positions within the nucleus that are heritable and tissue specific. Genes located at the nuclear periphery tend to be inactive and this negative regulation can be reversed when they are released from the periphery in certain differentiation systems. Recent work using specially designed systems has shown that genes can be artificially tethered to the nuclear periphery by an affinity mechanism. The next important step will be to identify the endogenous NE (nuclear envelope) and chromatin proteins that participate in affinity-driven NE tethering and determine how they are regulated.


Asunto(s)
Cromatina/metabolismo , Regulación de la Expresión Génica , Genoma , Membrana Nuclear/metabolismo , Animales , Núcleo Celular/metabolismo , Humanos
11.
J Chromatogr Sci ; 57(6): 511-517, 2019 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-30941395

RESUMEN

Direct resolution of (RS)-ketorolac and (RS)-etodolac has been achieved by ligand exchange thin layer chromatography. Cu(II) has been used as a complexing ion with three enantiomerically pure amino acids (namely, l-tryptophan, l-histidine and l-phenylalanine) as chiral dopants. Chromatograms were developed using different combinations of solvent systems in different ratio having no chiral additive. Iodine vapors were used for location of spots. Different experimental factors, i.e., effect of temperature, mole ratio of Cu(II) to l-amino acids and solvent ratio were optimized in order to improve the separation efficiency. Results have been compared (for RF and Rs). Limit of detection for each enantiomer of both the racemic analytes (ketorolac and etodolac) was found to be 0.6 and 0.8µg.

12.
Methods Mol Biol ; 2030: 219-236, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31347121

RESUMEN

Enantioseparation studies of proteinogenic, non-proteinogenic, and dansyl amino acids are described herein by using liquid chromatographic techniques, i.e., HPLC and TLC. A researcher who wants to perform amino acid (AA) analysis or separate enantiomers of AAs by HPLC or TLC can follow the method. Figures included represent the actual experiments.Synthesis and application of chiral derivatizing reagents (CDRs) based on cyanuric chloride (CC) and difluorodinitrobenzene (DFDNB) have been described for AA analysis and enantioseparation by indirect approach. The methods represent pre-column derivatization of AAs and represent a good and less expensive substitute of AA analyzer. The application of commercial "Chiralplate" and use of erythromycin and L-tartaric acid have been described as chiral selector either as impregnating reagent in the stationary phase or as an additive in the mobile phase for direct enantioseparation by TLC. Application of the homemade TLC plates has also been described; the methods are successful in obtaining the native enantiomer as well.


Asunto(s)
Aminoácidos/aislamiento & purificación , Fraccionamiento Químico/métodos , Reactivos de Enlaces Cruzados/química , Aminoácidos/química , Fraccionamiento Químico/instrumentación , Cromatografía Líquida de Alta Presión/instrumentación , Cromatografía Líquida de Alta Presión/métodos , Cromatografía en Capa Delgada/instrumentación , Cromatografía en Capa Delgada/métodos , Dinitrofluorobenceno/análogos & derivados , Dinitrofluorobenceno/química , Eritromicina/química , Estereoisomerismo , Tartratos/química , Triazinas/química
13.
Subcell Biochem ; 43: 51-76, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17953391

RESUMEN

Most subcellular organelles are expected to be similar among different cell types; however, a recent study suggests a surprising amount of variation in the protein composition at the nuclear envelope. Therefore, to comprehensively identify proteins in subcellular organelles proteomics datasets may need to be generated from multiple cell types. In this chapter we describe a proteomics study that expanded the number of nuclear membrane proteins by 5-fold using a "subtractive" methodology in which a subcellular organelle is partially purified biochemically and partially purified in silico. The biochemical fraction of interest and a separate fraction enriched in proteins known to contaminate it, in this case nuclear envelopes and microsomes respectively, are first isolated and separately analyzed by mass spectrometry. For in silico purification, proteins appearing in both fractions are subtracted from the dataset in order to identify proteins that are unique to the organelle being investigated. This approach identified 67 novel putative nuclear envelope transmembrane proteins in rodent liver. Further analysis of their expression levels in other tissues indicates that several are preferentially expressed in liver cell types, which in turn predicts considerable variation in the nuclear envelope proteome among different cell types. Finally, we discuss several issues associated with confirming that these peptide-based identifications represent proteins that truly localize to the nuclear envelope. These studies have complicated rather than simplified our view of the nuclear envelope, but proteomics has set the stage for beginning to understand this highly complex subnuclear organelle.


Asunto(s)
Proteínas de la Membrana/química , Membrana Nuclear/química , Orgánulos/química , Proteoma , Animales , Humanos
14.
J Chromatogr Sci ; 56(1): 92-98, 2018 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-28977354

RESUMEN

Direct enantiomeric resolution of commonly used five racemic ß-adrenolytics, namely, bisoprolol, atenolol, propranolol, salbutamol and carvedilol has been achieved by thin layer chromatography using bovine serum albumin (BSA) as chiral additive in stationary phase. Successful resolution of the enantiomers of all racemic ß-adrenolytics was achieved by use of different composition of simple organic solvents having no buffer or inorganic ions. The effect of variation in pH, temperature, amount of BSA as the additive, and composition of mobile phase on resolution was systematically studied. Spots were visualized in iodine vapors. Native enantiomers for each of the five analytes were isolated and identified and their elution order was determined. The limit of detection was found to be 0.7, 1.2, 0.84, 1.6 and 0.9 µg (per spot) for each enantiomer of bisoprolol, atenolol, propranolol, salbutamol and carvedilol, respectively.


Asunto(s)
Agonistas de Receptores Adrenérgicos beta 2/análisis , Antagonistas Adrenérgicos beta/análisis , Cromatografía en Capa Delgada/métodos , Agonistas de Receptores Adrenérgicos beta 2/química , Antagonistas Adrenérgicos beta/química , Animales , Bovinos , Límite de Detección , Modelos Lineales , Reproducibilidad de los Resultados , Albúmina Sérica Bovina , Estereoisomerismo
15.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1061-1062: 117-122, 2017 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-28732286

RESUMEN

Enantioseparation of four commonly used ß-adrenolytics (bisoprolol, salbutamol, and carvedilol, marketed as racemic mixtures) has been achieved by both TLC and RPHPLC via an indirect approach. A new chiral reagent, (S)-naproxen benzotriazole ester, was synthesized and it was characterized by UV, IR, 1HNMR, elemental analysis and polarimetry. It was used to synthesize diastereomeric derivatives of the three ß-adrenolytics under microwave irradiation. TLC separation of diastereomeric derivatives was achieved which were then isolated by preparative approach; these were characterized and were used as standard reference for determining absolute configuration of diastereomeric derivatives and for establishing validated HPLC method for enantioseparation and sensitive detection of the three ß-adrenolytics in human plasma. Mobile phase in gradient mode containing methanol and aqueous triethylaminephosphate (TEAP) was successful for HPLC separation; conditions with respect to pH, flow rate, and buffer concentration were optimized. The method is capable to accurately quantitate ß-adrenolytics in human plasma with minimal sample clean-up and rapid separation by TLC and RPHPLC. The limit of detection values were 0.97 and 0.87ng/mL for diastereomeric derivatives of (S)- and (R)-bisoprolol, respectively, which are very low in comparison to literature reports.


Asunto(s)
Agonistas de Receptores Adrenérgicos beta 2/sangre , Agonistas de Receptores Adrenérgicos beta 2/aislamiento & purificación , Antagonistas Adrenérgicos beta/sangre , Antagonistas Adrenérgicos beta/aislamiento & purificación , Cromatografía Líquida de Alta Presión/métodos , Agonistas de Receptores Adrenérgicos beta 2/química , Antagonistas Adrenérgicos beta/química , Albuterol/sangre , Albuterol/química , Albuterol/aislamiento & purificación , Bisoprolol/sangre , Bisoprolol/química , Bisoprolol/aislamiento & purificación , Carbazoles/sangre , Carbazoles/química , Carbazoles/aislamiento & purificación , Carvedilol , Humanos , Límite de Detección , Modelos Lineales , Naproxeno/química , Propanolaminas/sangre , Propanolaminas/química , Propanolaminas/aislamiento & purificación , Reproducibilidad de los Resultados , Estereoisomerismo , Triazoles/química
16.
Nucleic Acids Res ; 32(18): 5553-69, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15486205

RESUMEN

ORF57 protein of Kaposi's sarcoma-associated herpesvirus has a counterpart in all herpesvirus of mammals and birds and regulates gene expression at transcriptional and post-transcriptional levels. ORF57 was capable of self-interaction and bound a rapidly migrating form of heterogeneous nuclear ribonucleoprotein K (hnRNP K), a multifunctional cellular protein involved in gene expression. In virus infected cell extracts, ORF57 was present in a complex with hnRNP K that had protein kinase CK2 activity, and was phosphorylated by CK2. Different regions of ORF57 bound both catalytic alpha/alpha' and regulatory beta subunits of CK2. CK2 modification enhanced the ORF57-hnRNP K interaction, and may regulate the presence and activities of components in the complex. We suggest that ORF57 and hnRNP K interaction may modulate ORF57-mediated regulation of viral gene expression. Herpesviral ORF57 (Rhadinovirus) and ICP27 (Simplexvirus) proteins both interact with hnRNP K and CK2 implying that adaptation of the ancestral hnRNP K and CK2 to associate with viral regulatory ancestor protein likely pre-dates divergence of these Herpesviridae genera that occurred 200 million years ago.


Asunto(s)
Quinasa de la Caseína II/metabolismo , Herpesvirus Humano 8/fisiología , Ribonucleoproteína Heterogénea-Nuclear Grupo K/metabolismo , Sarcoma de Kaposi/virología , Proteínas Virales/metabolismo , Secuencia de Aminoácidos , Sitios de Unión , Extractos Celulares , Células HeLa , Herpesvirus Humano 8/efectos de los fármacos , Herpesvirus Humano 8/genética , Ribonucleoproteína Heterogénea-Nuclear Grupo K/química , Ribonucleoproteína Heterogénea-Nuclear Grupo K/genética , Humanos , Inmunoprecipitación , Datos de Secuencia Molecular , Complejos Multiproteicos/química , Complejos Multiproteicos/metabolismo , Fosforilación , Unión Proteica , Proteínas Virales/química , Proteínas Virales/genética , Replicación Viral/efectos de los fármacos
17.
J Chromatogr Sci ; 54(5): 842-6, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26896346

RESUMEN

A new chromatographic method has been developed for direct enantioresolution of (RS)-baclofen by ligand-exchange thin-layer chromatography (TLC) adopting two different approaches; (A) TLC plates were prepared by mixing the ligand exchange reagents (LER) with silica gel slurry and the chromatograms were developed with different achiral solvents or solvents having no chiral additive, and (B) the LER consisting of Cu(II)-L-amino acid complex was used as chiral mobile phase additive and the plain plates of silica gel having no chiral selector were used. Cu(II) acetate and four L-amino acids (namely, L-tryptophan, L-histidine, L-proline and L-phenylalanine) were used for the preparation of LERs. Spots were located by the use of iodine vapor. Effect of temperature and the mole ratio of Cu(II)-to-amino acid on enantioresolution were also studied. The results for the two methods have been compared, and the issue of involvement of the Cu(II) cation for the best performance of the two methods has been discussed with respect to the same mobile phase. L-Trp proved to be a good ligand using a common mobile phase in each case.


Asunto(s)
Baclofeno/análisis , Cromatografía en Capa Delgada/métodos , Ligandos , Estereoisomerismo , Temperatura
18.
Contemp Clin Dent ; 7(2): 232-5, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27307674

RESUMEN

Missing teeth are a common developmental abnormality in humans. It may manifest as absence of varying numbers of primary and/or secondary teeth. Early treatment and follow-up are the key to successful rehabilitation of young patients with congenitally missing teeth. It is critical that oral rehabilitation is started early to maintain and correct the oral functions. Mucosa borne removable prostheses are the commonly selected treatment options for the young patients who present with oligodontia or anodontia. This clinical report describes esthetic, functional, and psychological rehabilitation of a young boy with severe oligodontia in maxillary arch and anodontia in mandibular arch. The individualized conservative graded approach in prosthetic rehabilitation with removable acrylic prosthesis helped to achieve esthetics, functionality, and psychological benefits.

20.
PLoS One ; 9(11): e111851, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25386906

RESUMEN

Changes in the peripheral distribution and amount of condensed chromatin are observed in a number of diseases linked to mutations in the lamin A protein of the nuclear envelope. We postulated that lamin A interactions with nuclear envelope transmembrane proteins (NETs) that affect chromatin structure might be altered in these diseases and so screened thirty-one NETs for those that promote chromatin compaction as determined by an increase in the number of chromatin clusters of high pixel intensity. One of these, NET23 (also called STING, MITA, MPYS, ERIS, Tmem173), strongly promoted chromatin compaction. A correlation between chromatin compaction and endogenous levels of NET23/STING was observed for a number of human cell lines, suggesting that NET23/STING may contribute generally to chromatin condensation. NET23/STING has separately been found to be involved in innate immune response signaling. Upon infection cells make a choice to either apoptose or to alter chromatin architecture to support focused expression of interferon genes and other response factors. We postulate that the chromatin compaction induced by NET23/STING may contribute to this choice because the cells expressing NET23/STING eventually apoptose, but the chromatin compaction effect is separate from this as the condensation was still observed when cells were treated with Z-VAD to block apoptosis. NET23/STING-induced compacted chromatin revealed changes in epigenetic marks including changes in histone methylation and acetylation. This indicates a previously uncharacterized nuclear role for NET23/STING potentially in both innate immune signaling and general chromatin architecture.


Asunto(s)
Cromatina/metabolismo , Proteínas de la Membrana/metabolismo , Membrana Nuclear/metabolismo , Acetilación , Histonas/metabolismo , Humanos , Inmunidad Innata , Metilación
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