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1.
Plant Commun ; 2(4): 100174, 2021 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-34327319

RESUMO

SWI/SNF chromatin remodelers are evolutionarily conserved multiprotein complexes that use the energy of ATP hydrolysis to change chromatin structure. A characteristic feature of SWI/SNF remodelers is the occurrence in both the catalytic ATPase subunit and some auxiliary subunits, of bromodomains, the protein motifs capable of binding acetylated histones. Here, we report that the Arabidopsis bromodomain-containing proteins BRD1, BRD2, and BRD13 are likely true SWI/SNF subunits that interact with the core SWI/SNF components SWI3C and SWP73B. Loss of function of each single BRD protein caused early flowering but had a negligible effect on other developmental pathways. By contrast, a brd triple mutation (brdx3) led to more pronounced developmental abnormalities, indicating functional redundancy among the BRD proteins. The brdx3 phenotypes, including hypersensitivity to abscisic acid and the gibberellin biosynthesis inhibitor paclobutrazol, resembled those of swi/snf mutants. Furthermore, the BRM protein level and occupancy at the direct target loci SCL3, ABI5, and SVP were reduced in the brdx3 mutant background. Finally, a brdx3 brm-3 quadruple mutant, in which SWI/SNF complexes were devoid of all constituent bromodomains, phenocopied a loss-of-function mutation in BRM. Taken together, our results demonstrate the relevance of BRDs as SWI/SNF subunits and suggest their cooperation with the bromodomain of BRM ATPase.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Montagem e Desmontagem da Cromatina , Proteínas de Ligação a DNA/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Ligação a DNA/metabolismo , Domínios Proteicos
2.
Microorganisms ; 9(7)2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34202696

RESUMO

The development of coastal vermetid reefs and rocky shores depends on the activity of several reef builders, including red crustose coralline algae (CCA) such as Neogoniolithon sp. To initiate studies on the interaction between Neogoniolithon sp. and its associated bacteria, and their impact on the algae physiological performance, we characterized the bacterial community by 16S rRNA gene sequencing. These were extracted from the algal tissue and adjacent waters along two sampling campaigns (during winter and spring), in three study regions along a reef in the east Mediterranean Israeli coast and from laboratory-grown algae. The analysis revealed that aquaria and field communities differ substantially, suggesting that future research on Neogoniolithon sp. interaction with its microbiome must rest on aquaria that closely simulate coastal conditions. Some prokaryote classes found associated with the alga tissue were hardly detected or absent from surrounding water. Further, bacterial populations differed between sampling campaigns. One example is the presence of anaerobic bacteria and archaea families in one of the campaigns, correlating with the weaker turbulence in the spring season, probably leading to the development of local anoxic conditions. A better understanding of reef-building activity of CCA and their associated bacteria is necessary for assessment of their resilience to climate change and may support coastal preservation efforts.

3.
Nucleic Acids Res ; 48(20): 11347-11369, 2020 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-33104784

RESUMO

While transcription factors (TFs) are known to regulate the expression of their target genes (TGs), only a weak correlation of expression between TFs and their TGs has generally been observed. As lack of correlation could be caused by additional layers of regulation, the overall correlation distribution may hide the presence of a subset of regulatory TF-TG pairs with tight expression coupling. Using reported regulatory pairs in the plant Arabidopsis thaliana along with comprehensive gene expression information and testing a wide array of molecular features, we aimed to discern the molecular determinants of high expression correlation of TFs and their TGs. TF-family assignment, stress-response process involvement, short genomic distances of the TF-binding sites to the transcription start site of their TGs, few required protein-protein-interaction connections to establish physical interactions between the TF and polymerase-II, unambiguous TF-binding motifs, increased numbers of miRNA target-sites in TF-mRNAs, and a young evolutionary age of TGs were found particularly indicative of high TF-TG correlation. The modulating roles of post-transcriptional, post-translational processes, and epigenetic factors have been characterized as well. Our study reveals that regulatory pairs with high expression coupling are associated with specific molecular determinants.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas/genética , MicroRNAs/metabolismo , RNA Mensageiro/metabolismo , Fatores de Transcrição/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Sítios de Ligação/genética , DNA Polimerase II/genética , DNA Polimerase II/metabolismo , Bases de Dados Genéticas , Ontologia Genética , Redes Reguladoras de Genes , Genoma , Estudo de Associação Genômica Ampla , Genômica , Aprendizado de Máquina , MicroRNAs/genética , Análise de Sequência com Séries de Oligonucleotídeos , Regiões Promotoras Genéticas , Ligação Proteica , Mapas de Interação de Proteínas/genética , Processamento de Proteína Pós-Traducional , Processamento Pós-Transcricional do RNA , RNA Mensageiro/genética , Fatores de Transcrição/genética , Sítio de Iniciação de Transcrição
4.
Ginekol Pol ; 85(8): 633-4, 2014 Aug.
Artigo em Polonês | MEDLINE | ID: mdl-25219147

RESUMO

Ectopic pregnancy occurs in 0.5-2% of all pregnancies. A double ectopic pregnancy is very rare and has the incidence of 1 in 725 ectopic pregnancies. We describe a case of a 30-year-old patient with double ectopic pregnancy located in tubas in spontaneous cycle--diagnosed and treated at the Gynecology and Obstetrics Hospital in Walbrzych. The patient had no risk factors for ectopic pregnancy. This case shows that even the diagnosis of an evident ectopic pregnancy cannot exclude the possibility of a double ectopic pregnancy.


Assuntos
Tubas Uterinas/cirurgia , Gravidez Tubária/diagnóstico por imagem , Gravidez Tubária/cirurgia , Adulto , Tubas Uterinas/patologia , Feminino , Humanos , Laparotomia/métodos , Gravidez , Resultado do Tratamento , Ultrassonografia
5.
Psychiatr Pol ; 41(3): 319-28, 2007.
Artigo em Polonês | MEDLINE | ID: mdl-17900048

RESUMO

INTRODUCTION: Volumetric loss of some cerebral structures is noticed during morphometrical investigations, and it is one of the most frequent abnormalities in schizophrenic patients' brains. The new methods of MRI investigations show subtle changes in cerebral white matter, which are undetectable by standard MRI. The magnetic transfer imaging (MTI) may be used to estimate the structural integrity of white matter and allows for visualisation of minimal changes in cerebral tissue. AIM: The aim of this work was to estimate the cerebral tissue using magnetic transfer imaging and the analysis of magnetic transfer ratio (MTR) maps in schizophrenic patients. METHOD: We examined 15 patients with schizophrenia and 15 healthy volunteers. We used sequences of: SE, FLAIR and GE with- and without saturation pulse, acquiring standard T1- and T2-weighted anatomical images and images with magnetic transfer effect and without it. For quantitative estimation of magnetic transfer, the MTR-maps were calculated from a standard formula: MTR=Mo-Ms/Mo'l00%, and the obtained MTR-values, from regions of interest in schizophrenics were compared with MTR-values in healthy persons. RESULTS: Both, in the schizophrenic group and in the controls, MTR-values (from the analysed regions of white matter) were between 30-50%. We observed a statistically significant reduction of MTR of schizophrenic patients in the white matter of the left temporal and left frontal lobes. CONCLUSIONS: With the help of the technique and methods of statistical analysis, the identification of altered MTR-areas in patients with schizophrenia is possible. The results confirm the presence of areas of minimal injuries in schizophrenic persons' brain tissue, which are detectable using magnetic transfer imaging.


Assuntos
Encéfalo/patologia , Aumento da Imagem , Imageamento por Ressonância Magnética , Esquizofrenia/patologia , Adulto , Feminino , Lobo Frontal/patologia , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Lobo Occipital/patologia , Lobo Parietal/patologia , Valores de Referência , Lobo Temporal/patologia
6.
Psychiatr Pol ; 41(3): 309-18, 2007.
Artigo em Polonês | MEDLINE | ID: mdl-17900047

RESUMO

The structural abnormalities in brains of persons suffering from schizophrenia were noticed in neuropathological studies, pneumoencephalography, tomography and magnetic resonance imaging for a long time. The reduction of grey matter volume was present mainly in frontal and temporal lobes and also a decrease of total brain volume with an increase of ventricle volume was observed. The volumetric reduction of white matter was not observed. However, structural changes may not be present in each case and conventional MRI, even with high resolution images is not able to detect subtle changes which may have a functional significance. The new MRI techniques, e.g. magnetic transfer imaging (MTI), indicate the presence of changes in the white matter of schizophrenic's brains, which are not detectable by conventional MRI. MTI is based on decreasing of the signal intensity by the transfer of magnetization between saturated protons of water, bound to macromolecules of myelin and phospholipids in cell membranes and free water protons. This process may be used to estimate structural integrity of white and grey matter, to reveal the presence of subtle changes in brain tissue.


Assuntos
Encéfalo/patologia , Aumento da Imagem , Imageamento por Ressonância Magnética , Esquizofrenia/diagnóstico , Ventrículos Cerebrais/patologia , Lobo Frontal/patologia , Humanos , Processamento de Imagem Assistida por Computador , Lobo Temporal/patologia
7.
Psychiatr Pol ; 38(2): 283-96, 2004.
Artigo em Polonês | MEDLINE | ID: mdl-15307293

RESUMO

In the first part of this work the main problems of prion diseases--also called transmissible cerebral amyloidoses (TCA) or subacute (transmissible) encephalopathies (SSE, TSE)--and clinical symptoms of Creutzfeldt-Jakob disease are presented. Some problems of neuropathology of Creutzfeldt-Jakob disease and basic informations about other human prion diseases will be presented in the second part. The growth of the interest in prion diseases during last years is caused by the problem of bovine spongiform encephalopathy (BSE or "mad cow disease") and its transmission into a human. The new variant of Creutzfeldt-Jakob disease (nvCJD) has appeared. Prion diseases: Gerstmann-Sträussler-Scheinker syndrome (GSS), kuru, fatal familial insomnia (FFI) and particularly the most frequent of them--Creutzfeldt-Jakob disease (CJD)--have nonspecific, sometimes variable clinical (psychopathological and neurological) symptoms. The imaging, EEG, cerebrospinal fluid tests and other laboratory tests are not specific either and their diagnostic value is limited. Neuropathological studies are needed but their interpretation is often difficult. The only certain diagnostic marker for TSE is the presence of PrP(Sc), the prion protein, which is presently believed to be a direct cause for all transmissible cerebral amyloidoses (TCA).


Assuntos
Síndrome de Creutzfeldt-Jakob , Proteínas PrPC/isolamento & purificação , Doenças Priônicas , Animais , Bovinos , Síndrome de Creutzfeldt-Jakob/diagnóstico , Síndrome de Creutzfeldt-Jakob/transmissão , Diagnóstico Diferencial , Encefalopatia Espongiforme Bovina/diagnóstico , Encefalopatia Espongiforme Bovina/transmissão , Doença de Gerstmann-Straussler-Scheinker/diagnóstico , Doença de Gerstmann-Straussler-Scheinker/transmissão , Humanos , Insônia Familiar Fatal/diagnóstico , Insônia Familiar Fatal/transmissão , Kuru/diagnóstico , Kuru/transmissão , Doenças Priônicas/diagnóstico , Doenças Priônicas/transmissão , Fatores de Risco
8.
Psychiatr Pol ; 38(2): 297-309, 2004.
Artigo em Polonês | MEDLINE | ID: mdl-15307294

RESUMO

The second part of this work presents the neuropathological problems of the Creutzfeldt-Jakob disease and basic informations about other human prion diseases. General problems of prion diseases and clinical symptoms of Creutzfeldt-Jakob disease were presented in the first part. Prion diseases are also known as transmissible cerebral amyloidoses (TCA) or transmissible (subacute) spongiform encephalopathies (TSE, SSE). There are following human TSE's: Creutzfeldt-Jakob disease (CJD)--the most frequent TSE, and its new variant (vCJD)--a result of BSE's transmission into human, sometimes treated as a separate disease; also: Gerstmann-Sträussler-Scheinker syndrome (GSS) that may be a variant of familial CJD, kuru--probably a result of sporadic CJD's transmission by cannibalism, and fatal familial insomnia (FFI). Their clinical symptoms (and especially of the CJD), are nonspecific and sometimes variable. The imaging, EEG and other laboratory tests are not specific either. Neuropathological studies are needed but their interpretation may be equivocal. TSE's are characterised by the neurodegenerative process with characteristic spongiosis. However, vacuolisation--similar as in TSE-spongiosis--may occur in some CNS's disorders and in the case of putrescent brain tissue. In some cases of CJD, particularly those of long duration, the neuronal loss and astrocyte proliferation can mask the presence of spongiform changes, especially when vacuoles are not numerous. The only certain diagnostic marker for TSE is PrP(Sc), prion protein, presently believed to be a direct cause for all TSEs (TCAs). The PrP(Sc) has a dominant beta-sheet amyloid structure which makes its detection by immunohistochemical procedure possible only with special pretreatment, e.c.: hydrolytic autoclaving, hydrated autoclaving, incubations: formic acid (or guanidine thiocyanate) pretreatment, also combined pretreatments. These methods are standard diagnostic procedures for transmissible cerebral amyloidoses.


Assuntos
Encéfalo/patologia , Síndrome de Creutzfeldt-Jakob/patologia , Proteínas PrPC/análise , Doenças Priônicas/patologia , Animais , Autopsia , Bovinos , Diagnóstico Diferencial , Encefalopatia Espongiforme Bovina/patologia , Doença de Gerstmann-Straussler-Scheinker/patologia , Humanos , Insônia Familiar Fatal/patologia , Kuru/patologia , Proteínas PrPC/química , Fatores de Risco
9.
Pol J Pathol ; 54(1): 39-47, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12817879

RESUMO

Creutzfeldt-Jakob disease (CJD) in a proportion of cases may have nonspecific clinical signs and symptoms and no characteristic neuroimaging and EEG picture. Thus, neuropathological studies are mandatory for a diagnosis. However, spongiform change, neuronal loss and astrocyte proliferation--the hallmarks of prion diseases, may also be absent or variable. In such cases, the diagnosis should be supported by the detection of prion protein (PrP) by Western blotting or immunohistochemistry (ICC). PrP may not be visualised under "regular" conditions, but it is unmasked following pretreatment procedures: incubation in formic acid or guanidine thiocyanate, microwave treatment, and hydrated or hydrolytic autoclaving, and these methods were included in standard diagnostic procedures in several different protocols. The aim of this study was to compare the effectiveness of these pretreatment methods and to introduce an optimal protocol for our laboratory. For this purpose, we used brain sections of 11 cases of CJD, 1 case of Gerstmann-Sträussler-Scheinker syndrome (GSS), 1 case of kuru and 3 control brains. For pretreatment we used the hydrated and hydrolytic autoclaving and incubation with formic acid. Immunostaining was performed with monoclonal 3F4 antibody against PrP. The best results were achieved with hydrolytic autoclaving. By this procedure we were able to detect the "synaptic" type of PrP accumulation in all CJD cases, as well as in GSS and kuru, while with other two methods the signal was weaker or even absent.


Assuntos
Encéfalo/patologia , Imuno-Histoquímica/métodos , Proteínas PrPSc/metabolismo , Doenças Priônicas/patologia , Anticorpos Monoclonais , Encéfalo/metabolismo , Síndrome de Creutzfeldt-Jakob/metabolismo , Síndrome de Creutzfeldt-Jakob/patologia , Formiatos , Doença de Gerstmann-Straussler-Scheinker/metabolismo , Doença de Gerstmann-Straussler-Scheinker/patologia , Humanos , Ácido Clorídrico , Kuru/metabolismo , Kuru/patologia , Proteínas PrPSc/imunologia , Doenças Priônicas/metabolismo
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