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1.
Vaccines (Basel) ; 12(4)2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38675742

RESUMEN

Worldwide, cardiovascular diseases are the leading cause of mortality. This has significant implications for public health. Influenza, a common infectious disease, poses an increased risk for individuals with chronic conditions, such as cardiovascular diseases. However, little is known about influenza vaccination coverage in this group. This study utilized data from the Hungarian implementation of the European Health Interview Survey to assess influenza vaccination coverage and its determinants among cardiovascular respondents from 2009 to 2019. The findings reveal a downward trend in the vaccination rates over the years (from 24% to 21%), despite the availability of free vaccination in Hungary for this high-risk population. The main factors influencing low influenza vaccine uptake were identified, as follows: young age, a lower level of education, good self-perceived health status, smoking, a lower frequency of medical visits, and not suffering from respiratory diseases. Addressing these disparities necessitates targeted vaccination strategies supported by enhanced education, better access to healthcare services, and the promotion of preventive healthcare measures. Improving vaccination coverage among patients with cardiovascular diseases is imperative for reducing influenza-related morbidity and mortality. This highlights the importance of comprehensive public health interventions and healthcare provider engagement in promoting vaccination among groups at increased risk.

2.
BMC Public Health ; 23(1): 1679, 2023 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-37653363

RESUMEN

BACKGROUND: In 2020, globally 685,000 people died, and 2.3 million women were diagnosed with breast cancer. The main cause of cancer deaths among women is breast cancer, which account for 15.5% of all cancer deaths. Most of these could have been avoided with timely diagnosis. The aim of our study was to determine the proportion of breast screening participation in Hungary, and to identify possible factors that may influence breast screening attendance. METHODS: Our data were gathered from the cross-sectional European Health Interview Surveys conducted in Hungary in 2009, 2014, and 2019. In terms of categorical characteristics, Pearson's chi-square test was performed to evaluate the differences between people who have attended breast screening within two years and who have only attended more than two years ago. To determine the factors that may have an impact on the uptake of screening, generalized linear model with logit link function regarding binomial probability distribution was executed. RESULTS: The responses of 2626 women between the age 45-65 were included in our study. In 2009 85% (n=741), in 2014 90% (n=851) and in 2019 87% (n=699) of the respondents claimed to have ever attended a breast screening in their life. In 2009 68% (n=594), in 2014 66% (n=630) and in 2019 64% (n=515) said that they have taken part in breast screening within two years (p=0.331). From 2014 to 2019 (AOR=0.72 [0.57-0.89]) the chance of attending breast screening was decreasing. We observed that both secondary (AOR=1.97 [1.60-2.44]) and tertiary educational level (AOR=2.23 [1.67-3.00]), higher perceived income (AOR=1.54 [1.25-1.90]), and more frequent meeting with the doctor (AOR=1.77 [1.39-2.27]) and with the specialist (AOR=1.88 [1.54-2.28]) appeared as protective factors of breast screening attendance. CONCLUSIONS: Our results show that the lifetime prevalence of breast screening participation is high, however the recommended biennial rate is relatively low. To increase the participation rate, various initiatives would be needed, especially for women in identified risk groups, which are lower educational level, lower perceived income, and less frequent meeting with the doctor and with the specialist.


Asunto(s)
Neoplasias de la Mama , Detección Precoz del Cáncer , Femenino , Humanos , Persona de Mediana Edad , Anciano , Neoplasias de la Mama/diagnóstico , Estudios Transversales , Hungría/epidemiología , Encuestas y Cuestionarios
3.
BMC Health Serv Res ; 19(1): 823, 2019 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-31711483

RESUMEN

BACKGROUND: Genomic screening has unique challenges which makes it difficult to easily implement on a wide scale. If the costs, benefits and tradeoffs of investing in genomic screening are not evaluated properly, there is a risk of wasting finite healthcare resources and also causing avoidable harm. MAIN TEXT: If healthcare professionals - including policy makers, payers and providers - wish to incorporate genomic screening into healthcare while minimizing waste, maximizing benefits, and considering results that matter to patients, using the principles of triple value (allocative, technical, and personal value) could help them to evaluate tough decisions and tradeoffs. Allocative value focuses on the optimal distribution of limited healthcare resources to maximize the health benefits to the entire population while also accounting for all the costs of care delivery. Technical value ensures that for any given condition, the right intervention is chosen and delivered in the right way. Various methods (e.g. ACCE, HTA, and Wilson and Jungner screening criteria) exist that can help identify appropriate genomic applications. Personal value incorporates preference based informed decision making to ensure that patients are informed about the benefits and harms of the choices available to them and to ensure they make choices based on their values and preferences. CONCLUSIONS: Using triple value principles can help healthcare professionals make reasoned and tough judgements about benefits and tradeoffs when they are exploring the role genomic screening for chronic diseases could play in improving the health of their patients and populations.


Asunto(s)
Enfermedad Crónica/prevención & control , Genómica/normas , Neoplasias de la Mama/genética , Neoplasias de la Mama/prevención & control , Toma de Decisiones , Atención a la Salud/métodos , Diagnóstico Precoz , Femenino , Predisposición Genética a la Enfermedad/prevención & control , Pruebas Genéticas/normas , Genómica/métodos , Personal de Salud , Humanos , Mutación/genética
4.
BMJ Open ; 8(2): e019232, 2018 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-29391381

RESUMEN

OBJECTIVE: Quantitative studies have shown the various benefits for having accreditation in hospitals. However, neither of these explored the general conditions before applying for an accreditation. To close this gap, this study aimed to investigate the possible association between joining an accreditation programme with various hospital characteristics. DESIGN: A cross-sectional study was implemented using the databases of the 2013 Hungarian hospital survey and of the Hungarian State Treasury. SETTING: Public general hospitals in Hungary. PARTICIPANTS: The analysis involved 44 public general hospitals, 14 of which joined the preparatory project for a newly developed accreditation programme. MAIN OUTCOME MEASURES: The outcomes included the percentage of compliance in quality management, patient information and identification, internal professional regulation, safe surgery, pressure sore prevention, infection control, the opinions of the heads of quality management regarding the usefulness of quality management and clinical audits, and finally, the total debt of the hospital per bed and per discharged patient. RESULTS: According to our findings, the general hospitals joining the preparatory project of the accreditation programme performed better in four of the six investigated activities, the head of quality management had a better opinion on the usefulness of quality management, and both the debt per bed number and the debt per discharged patient were lower than those who did not join. However, no statistically significant differences between the two groups were found in any of the examined outcomes. CONCLUSIONS: The findings suggest that hospitals applying for an accreditation programme do not differ significantly in characteristics from those which did not apply. This means that if in the future the accredited hospitals become better than other hospitals, then the improvement could be solely contributed to the accreditation.


Asunto(s)
Acreditación , Adhesión a Directriz , Hospitales Públicos , Garantía de la Calidad de Atención de Salud/normas , Calidad de la Atención de Salud/normas , Acreditación/normas , Estudios Transversales , Hospitales Públicos/normas , Humanos , Hungría , Objetivos Organizacionales , Evaluación de Resultado en la Atención de Salud/normas , Garantía de la Calidad de Atención de Salud/organización & administración
5.
Stem Cells Dev ; 26(23): 1724-1733, 2017 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-28992793

RESUMEN

Free fatty acid receptor 2 (FFAR2, also known as GPR43) is a G-protein-coupled receptor activated by short-chain fatty acids that are produced by gut microbiota through fermentation of nondigestible carbohydrates. FFAR2 functions as a metabolic sensor and is expressed in metabolically active tissues, such as adipose tissue. Earlier studies proved the connection between FFAR2 and adipocyte differentiation in mice. The aim of this study was to investigate the implication of FFAR2 receptor in adipogenesis in human chorion-derived mesenchymal stem cells (cMSCs). The short-chain fatty acid, propionate, and phenylacetamide a selective FFAR2 agonist resulted in a marked suppression of lipid droplet accumulation during the adipogenic differentiation of cMSCs. Western blot studies revealed that FFAR2 was detectable at any time point of the differentiation period. The direct involvement of FFAR2 in the differentiation into adipocytes was proven by the downregulation of its gene expression in cMSCs by lentiviral messenger RNA (mRNA) silencing transduction particles. Our results showed that a significant suppression in lipid accumulation upon FFAR2 agonist treatments was elicited by FFAR2-silencing. Based on these results we suggest that propionate inhibits the formation of adipocytes from MSCs and acts on adipogenesis predominantly via FFAR2.


Asunto(s)
Adipocitos/citología , Diferenciación Celular , Células Madre Mesenquimatosas/citología , Propionatos/farmacología , Receptores de Superficie Celular/metabolismo , Adipocitos/metabolismo , Células Cultivadas , Corion/citología , Humanos , Gotas Lipídicas/metabolismo , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/metabolismo
6.
Microbiology (Reading) ; 162(12): 2116-2125, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27902418

RESUMEN

The glucocorticoid betamethasone (BM) is frequently employed in clinical practice because of its anti-inflammatory and immunosuppressive properties. In this study, we investigated the effect of BM (1 and 2 mM) on the ability of Candida albicans to adhere to, invade and damage oral, intestinal or vaginal epithelial cells, as well as to elicit cytokine and chemokine release. BM at 2 mM concentration stimulated adherence of C. albicans to vaginal cells and facilitated the invasion of intestinal and vaginal epithelia without influencing the growth rate of invading C. albicans hyphae at any type of epithelia and BM concentrations tested. In addition, BM at 2 mM concentration also augmented C. albicans-initiated cell damage of oral and intestinal cells. Furthermore, BM exposure decreased IL-6 cytokine and IL-8 chemokine release from oral and vaginal epithelial cells and also IL-6 release from intestinal epithelium after infection with C. albicans. These observations suggest that high-dose applications of BM may predispose patients to various epithelial C. albicans infections.


Asunto(s)
Betametasona/farmacología , Candida albicans/efectos de los fármacos , Candidiasis/microbiología , Células Epiteliales/microbiología , Glucocorticoides/farmacología , Candida albicans/crecimiento & desarrollo , Candida albicans/fisiología , Candidiasis/metabolismo , Línea Celular , Células Epiteliales/metabolismo , Humanos , Interleucina-6/metabolismo , Interleucina-8/metabolismo
7.
PLoS One ; 11(8): e0160965, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27504636

RESUMEN

Protein phosphatase Z (Ppz) is a fungus specific enzyme that regulates cell wall integrity, cation homeostasis and oxidative stress response. Work on Saccharomyces cerevisiae has shown that the enzyme is inhibited by Hal3/Vhs3 moonlighting proteins that together with Cab3 constitute the essential phosphopantothenoylcysteine decarboxylase (PPCDC) enzyme. In Candida albicans CaPpz1 is also involved in the morphological changes and infectiveness of this opportunistic human pathogen. To reveal the CaPpz1 regulatory context we searched the C. albicans database and identified two genes that, based on the structure of their S. cerevisiae counterparts, were termed CaHal3 and CaCab3. By pull down analysis and phosphatase assays we demonstrated that both of the bacterially expressed recombinant proteins were able to bind and inhibit CaPpz1 as well as its C-terminal catalytic domain (CaPpz1-Cter) with comparable efficiency. The binding and inhibition were always more pronounced with CaPpz1-Cter, indicating a protective effect against inhibition by the N-terminal domain in the full length protein. The functions of the C. albicans proteins were tested by their overexpression in S. cerevisiae. Contrary to expectations we found that only CaCab3 and not CaHal3 rescued the phenotypic traits that are related to phosphatase inhibition by ScHal3, such as tolerance to LiCl or hygromycin B, requirement for external K+ concentrations, or growth in a MAP kinase deficient slt2 background. On the other hand, both of the Candida proteins turned out to be essential PPCDC components and behaved as their S. cerevisiae counterparts: expression of CaCab3 and CaHal3 rescued the cab3 and hal3 vhs3 S. cerevisiae mutations, respectively. Thus, both CaHal3 and CaCab3 retained the PPCDC related functions and have the potential for CaPpz1 inhibition in vitro. The fact that only CaCab3 exhibits its phosphatase regulatory potential in vivo suggests that in C. albicans CaCab3, but not CaHal3, acts as a moonlighting protein.


Asunto(s)
Candida albicans/enzimología , Carboxiliasas/metabolismo , Fosfoproteínas Fosfatasas/metabolismo , Subunidades de Proteína/metabolismo , Candida albicans/fisiología , Infecciones Oportunistas/microbiología , Fosfoproteínas Fosfatasas/química , Filogenia
8.
Plant Mol Biol ; 87(1-2): 125-41, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25398395

RESUMEN

The phosphorylation of plant retinoblastoma-related (RBR) proteins by cyclin-dependent kinases (CDKs) is well documented, but the counteracting phosphatases have not been identified yet. We report here that rice retinoblastoma-related protein-1 (OsRBR1) interacted with the B″ subunit of rice protein phosphatase 2A (OsPP2A B″) and underwent reversible phosphorylation during the cell division cycle. The OsRBR1-OsPP2A B" association required B domain in OsRBR1 and the C-terminal region of OsPP2A B″. We found by immunoprecipitation that OsPP2A B″, OsPP2A catalytic subunit subtype II, PSTAIRE-type CDK and OsRBR1 were in the same protein complex, indicating a physical association between the phosphatase, the kinase and their common substrate. OsPP2A B″ contains three predicted CDK phosphorylation sites: Ser95, Ser102 and Ser119. The in vitro phosphorylation of Ser95 and Ser119 with PSTAIRE-kinases was verified by mass spectrometry. We generated a series of phosphorylation site mutants to mimic the dephosphorylated or phosphorylated states of OsPP2A B″, and confirmed that all of the three predicted sites can be phosphorylated. Yeast two-hybrid experiments suggested that the phosphorylation of OsPP2A B″ promoted the formation of the OsPP2A holoenzyme. A triple phosphorylation mimicking OsPP2A B″ mutant containing holoenzyme showed higher activity in phosphatase assays. Our data collectively show that the phosphatase activity of OsPP2A against OsRBR1 is regulated by the phosphorylation of its B″ regulatory subunit. However, the analysis of the effect of okadaic acid, a phosphatase inhibitor, in rice cell suspension cultures revealed that the dephosphorylation of OsRBR1 was completely inhibited only by high dose (300 nM) of the okadaic acid during the cell cycle progression. Therefore the role of the protein phosphatase 1 should be considered as an additional post translational regulatory component of RBR protein function in higher plants.


Asunto(s)
Oryza/metabolismo , Proteína Fosfatasa 2/metabolismo , Proteína de Retinoblastoma/metabolismo , Secuencia de Aminoácidos , Western Blotting , Dominio Catalítico , Cromatografía Liquida , Quinasas Ciclina-Dependientes/metabolismo , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Fosforilación , Proteína Fosfatasa 2/química , Proteína Fosfatasa 2/genética , Espectrometría de Masas en Tándem , Técnicas del Sistema de Dos Híbridos
9.
Mol Microbiol ; 90(2): 367-82, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23962284

RESUMEN

Saccharomyces cerevisiae Hal3 and Vhs3 are moonlighting proteins, forming an atypical heterotrimeric decarboxylase (PPCDC) required for CoA biosynthesis, and regulating cation homeostasis by inhibition of the Ppz1 phosphatase. The Schizosaccharomyces pombe ORF SPAC15E1.04 (renamed as Sp hal3) encodes a protein whose amino-terminal half is similar to Sc Hal3 whereas its carboxyl-terminal half is related to thymidylate synthase (TS). We show that Sp Hal3 and/or its N-terminal domain retain the ability to bind to and modestly inhibit in vitro S. cerevisiae Ppz1 as well as its S. pombe homolog Pzh1, and also exhibit PPCDC activity in vitro and provide PPCDC function in vivo, indicating that Sp Hal3 is a monogenic PPCDC in fission yeast. Whereas the Sp Hal3 N-terminal domain partially mimics Sc Hal3 functions, the entire protein and its carboxyl-terminal domain rescue the S. cerevisiae cdc21 mutant, thus proving TS function. Additionally, we show that the 70 kDa Sp Hal3 protein is not proteolytically processed under diverse forms of stress and that, as predicted, Sp hal3 is an essential gene. Therefore, Sp hal3 represents a fusion event that joined three different functional activities in the same gene. The possible advantage derived from this surprising combination of essential proteins is discussed.


Asunto(s)
Carboxiliasas/metabolismo , Fusión Génica , Genes Fúngicos , Proteínas de Schizosaccharomyces pombe/metabolismo , Schizosaccharomyces/genética , Schizosaccharomyces/metabolismo , Timidilato Sintasa/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Genes Esenciales , Sistemas de Lectura Abierta , Fosfoproteínas Fosfatasas/genética , Fosfoproteínas Fosfatasas/metabolismo , Proteínas Recombinantes , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Schizosaccharomyces pombe/genética , Homología de Secuencia de Aminoácido , Timidilato Sintasa/genética
10.
BMC Dev Biol ; 12: 20, 2012 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-22827336

RESUMEN

BACKGROUND: Calpains are calcium regulated intracellular cysteine proteases implicated in a variety of physiological functions and pathological conditions. The Drosophila melanogaster genome contains only two genes, CalpA and CalpB coding for canonical, active calpain enzymes. The movement of the border cells in Drosophila egg chambers is a well characterized model of the eukaryotic cell migration. Using this genetically pliable model we can investigate the physiological role of calpains in cell motility. RESULTS: We demonstrate at the whole organism level that CalpB is implicated in cell migration, while the structurally related CalpA paralog can not fulfill the same function. The downregulation of the CalpB gene by mutations or RNA interference results in a delayed migration of the border cells in Drosophila egg chambers. This phenotype is significantly enhanced when the focal adhesion complex genes encoding for α-PS2 integrin ( if), ß-PS integrin (mys) and talin (rhea) are silenced. The reduction of CalpB activity diminishes the release of integrins from the rear end of the border cells. The delayed migration and the reduced integrin release phenotypes can be suppressed by expressing wild-type talin-head in the border cells but not talin-head(R367A), a mutant form which is not able to bind ß-PS integrin. CalpB can cleave talin in vitro, and the two proteins coimmunoprecipitate from Drosophila extracts. CONCLUSIONS: The physiological function of CalpB in border cell motility has been demonstrated in vivo. The genetic interaction between the CalpB and the if, mys, as well as rhea genes, the involvement of active talin head-domains in the process, and the fact that CalpB and talin interact with each other collectively suggest that the limited proteolytic cleavage of talin is one of the possible mechanisms through which CalpB regulates cell migration.


Asunto(s)
Calpaína/metabolismo , Movimiento Celular , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/citología , Drosophila melanogaster/metabolismo , Animales , Drosophila melanogaster/embriología , Drosophila melanogaster/genética , Adhesiones Focales/metabolismo , Talina/metabolismo
11.
Dev Genes Evol ; 220(3-4): 123-8, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20632030

RESUMEN

In the genome of Drosophila melanogaster, there are 19 phosphoprotein phosphatase (PPP) catalytic subunit coding genes. Seven of the novel members of the gene family turned out to be Drosophila-specific. The expression and evolution of these genes was investigated in the present study. CG11597 is a recently evolved gene that is expressed during all stages of morphogenesis in D. melanogaster. In contrast, the transcription of PpD5, PpD6, Pp1-Y1, and Pp1-Y2 genes is restricted to the pupa and imago developmental stages and to the testis of the males, just as that of the previously characterized PpY-55A and PpN58A. With the exception of the Y-localized Pp1-Y1 and Pp1-Y2, the testis-specific phosphatase genes are expressed in X/0 males, while none of them are expressed in XX/Y females. The mRNA of PpD5, Pp1-Y1, and PpY-55A were detected in the developing cysts by in situ hybridization, in contrast with the PpD6 transcript that was found in the distal ends of elongating spermatids. The latter localization suggests post-meiotic expression. The comparison of PPP genes in five Drosophila species revealed that the sequence of the six testis-specific phosphatases changed more rapidly than that of the housekeeping phosphatases. Our results support the "faster male" hypothesis. On the other hand, the male-biased expression of the six genes remained conserved during evolution despite the fact that Pp1-Y1, Pp1-Y2, and PpD6 moved from autosomes to the Y chromosome. Interestingly, the PpD6 gene was found to be Y-linked only in Drosophila ananassae.


Asunto(s)
Proteínas de Drosophila/genética , Drosophila/genética , Perfilación de la Expresión Génica , Fosfoproteínas Fosfatasas/genética , Animales , Cromosomas de Insectos/genética , Drosophila/clasificación , Drosophila/crecimiento & desarrollo , Drosophila melanogaster/genética , Drosophila melanogaster/crecimiento & desarrollo , Evolución Molecular , Femenino , Regulación del Desarrollo de la Expresión Génica , Regulación Enzimológica de la Expresión Génica , Hibridación in Situ , Isoenzimas/genética , Masculino , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores Sexuales , Especificidad de la Especie , Testículo/crecimiento & desarrollo , Testículo/metabolismo , Cromosoma Y/genética
12.
FEBS J ; 276(17): 4959-72, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19694808

RESUMEN

Calpain B is one of the two catalytically competent calpain (calcium-activated papain) isoenzymes in Drosophila melanogaster. Because structural predictions hinted at the presence of several potential phosphorylation sites in this enzyme, we investigated the in vitro phosphorylation of the recombinant protein by protein kinase A as well as by the extracellular signal-regulated protein kinases (ERK) 1 and 2. By MS, we identified Ser845 in the Ca2+ binding region of an EF-hand motif, and Ser240 close to the autocatalytic activation site of calpain B, as being the residues phosphorylated by protein kinase A. In the transducer region of the protease, Thr747 was shown to be the target of the ERK phosphorylation. Based on the results of three different assays, we concluded that the treatment of calpain B with protein kinase A and ERK1 and ERK2 kinases increases the rate of the autoproteolytic activation of the enzyme, together with the rate of the digestion of external peptide or protein substrates. Phosphorylation also elevates the Ca2+ sensitivity of the protease. The kinetic analysis of phosphorylation mimicking Thr747Glu and Ser845Glu calpain B mutants confirmed the above conclusions. Out of the three phosphorylation events tested in vitro, we verified the in vivo phosphorylation of Thr747 in epidermal growth factor-stimulated Drosophila S2 cells. The data obtained suggest that the activation of the ERK pathway by extracellular signals results in the phosphorylation and activation of calpain B in fruit flies.


Asunto(s)
Calpaína/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/enzimología , Secuencia de Aminoácidos , Animales , Calcio/metabolismo , Calpaína/genética , Células Cultivadas , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Proteínas de Drosophila/genética , Activación Enzimática , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Fosforilación , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
13.
Proc Natl Acad Sci U S A ; 104(38): 14964-9, 2007 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-17848525

RESUMEN

By using a microscopic approach, field inversion single-cell gel electrophoresis, we show that preformed single-strand discontinuities are present in the chromatin of resting and proliferating mammalian and yeast cells. These single-strand breaks are primarily nicks positioned at approximately 50-kbp intervals throughout the entire genome that could be efficiently labeled in situ by DNA polymerase I holoenzyme but not by Klenow fragment and terminal transferase unless after ribonucleolytic treatments. The RNA molecules involved appear to comprise R-loops, recognized by the S9.6 RNA/DNA hybrid-specific antibody. By using the breakpoint cluster region of the Mixed Lineage Leukemia (MLL) gene as a model, we have found that the number of manifest nicks detected by FISH performed after field inversion single-cell gel electrophoresis depends on epigenetic context, but the difference between germ-line and translocated MLL alleles is abolished by protease treatment. Our data imply that the double-stranded genomic DNA is composed of contiguous rather than continuous single strands and reveal an aspect of higher-order chromatin organization with ribonucleoprotein-associated persistent nicks defining approximately 50-kbp domains.


Asunto(s)
Roturas del ADN de Cadena Simple , Ribonucleoproteínas/química , Proliferación Celular , Células Cultivadas , Cromatina/ultraestructura , Ensayo Cometa , ADN/metabolismo , Fragmentación del ADN , Humanos , Hibridación Fluorescente in Situ , Células Jurkat , Proteína de la Leucemia Mieloide-Linfoide/genética , Proteína de la Leucemia Mieloide-Linfoide/metabolismo , ARN/metabolismo , Ribonucleoproteínas/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo
14.
Arch Biochem Biophys ; 451(1): 59-67, 2006 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-16631104

RESUMEN

Protein phosphatase Y (PPY) is a Drosophila testis-specific enzyme of unknown function. In a yeast two-hybrid screen we identified CG15031/PPYR1 as a PPY interacting protein. The specificity of the protein-protein interaction was proven by directed two-hybrid tests. The complex formation between PPY and PPYR1 was confirmed under in vitro and in vivo conditions by plasmon resonance spectroscopy, co-immunoprecipitation, and pull down experiments. Recombinant PPYR1 expressed in Escherichia coli is a heatstable, protease sensitive, intrinsically unstructured RNA-binding protein that migrates anomalously in SDS-polyacrylamide gel electrophoresis. It can be phosphorylated by cAMP-dependent protein kinase in vitro. PPYR1 moderately inhibits PPY activity, the inhibitory potential of the protein is slightly increased by phosphorylation. We suggest that PPYR1 may function as a scaffolding protein that targets PPY to RNA and other protein partners in Drosophila melanogaster.


Asunto(s)
Proteínas de Drosophila/metabolismo , Fosfoproteínas Fosfatasas/metabolismo , Receptores de Neuropéptido Y/metabolismo , Animales , Secuencia de Bases , Sitios de Unión , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Proteínas de Drosophila/genética , Drosophila melanogaster , Electroforesis en Gel de Poliacrilamida , Escherichia coli/genética , Fosfoproteínas Fosfatasas/genética , Fosforilación , Proteínas de Unión al ARN/metabolismo , Receptores de Neuropéptido Y/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Resonancia por Plasmón de Superficie
15.
Histochem Cell Biol ; 125(1-2): 63-73, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16195888

RESUMEN

Phenomena involving the disassembly of chromosomes to approximately 50 kbp double-stranded fragments upon protein denaturing treatments of normal and apoptotic mammalian nuclei as well as yeast protoplasts may be an indication of special, hypersensitive regions positioned regularly at loop-size intervals in the eukaryotic chromatin. Here we show evidence in yeast cell systems that loop-size fragmentation can occur in any phase of the cell cycle and that the plating efficiency of these cells is approximately 100%. The possibility of sequence specificity was investigated within the breakpoint cluster region (bcr) of the human MLL gene, frequently rearranged in certain leukemias. Our data suggest that DNA isolated from yeast cultures or mammalian cell lines carry nicks or secondary structures predisposing DNA for a specific nicking activity, at non-random positions. Furthermore, exposure of MLL bcr-carrying plasmid DNA to S1 nuclease or nuclear extracts or purified topoisomerase II elicited cleavages at the nucleotide positions of nick formation on human genomic DNA. These data support the possibility that certain sequence elements are preferentially involved in the cleavage processes responsible for the en masse disassembly of chromatin to loop-size fragments upon isolation of DNA from live eukaryotic cells.


Asunto(s)
Cromatina/ultraestructura , Células Eucariotas/ultraestructura , Apoptosis , Ciclo Celular/fisiología , Núcleo Celular/metabolismo , Núcleo Celular/ultraestructura , Cromosomas Fúngicos/genética , Cromosomas Fúngicos/metabolismo , ADN/biosíntesis , ADN/genética , Fragmentación del ADN , Replicación del ADN , Electroforesis en Gel de Agar , Citometría de Flujo , N-Metiltransferasa de Histona-Lisina , Humanos , Microscopía Confocal , Proteína de la Leucemia Mieloide-Linfoide/genética , Desnaturalización Proteica , Saccharomyces cerevisiae/metabolismo , Endonucleasas Específicas del ADN y ARN con un Solo Filamento/química
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