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1.
Dokl Biochem Biophys ; 494(1): 261-265, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33119830

RESUMO

Proliferation of mammalian cells is often accompanied by an increase in the content of the nucleolar proteins, which allows researchers to consider such proteins as potential activation markers. To test this assumption experimentally, we examined the expression pattern of the nucleolar rRNA processing factor SURF6 in normal (resting) peripheral blood lymphocytes, lymphocytes activated for proliferation in vitro, and in blood samples from patients with lymphoproliferative diseases. Using two methods (immunofluorescence and immunoblotting), we for the first time showed that the SURF6 protein is not detected in normal lymphocytes but can easily be visualized in lymphocytes after PHA activation and in lymphocytes of lymphocytic leukemia patients. The level of SURF6 expression in patients correlated with the aggressiveness of the disease development determined by the content of Ki-67-positive lymphocytes. These results allow the SURF6 nucleolar protein to be considered as a putative activation marker of lymphocytes in human blood disorders.


Assuntos
Linfócitos/imunologia , Transtornos Linfoproliferativos/metabolismo , Proteínas Nucleares/biossíntese , Biomarcadores/metabolismo , Estudos de Casos e Controles , Nucléolo Celular/imunologia , Humanos , Ativação Linfocitária , Linfócitos/citologia , Transtornos Linfoproliferativos/patologia , Proteínas Nucleares/imunologia , RNA Ribossômico/metabolismo
2.
Bull Exp Biol Med ; 168(3): 385-389, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31938908

RESUMO

We studied the influence of the estrous cycle on the morphology of preovulatory (germinal vesicle, GV) oocytes in mice and their capacity to meiotic maturation in vitro. After standard injections of eCG gonadotropin (PMSG, Follimag) to females at different stages of the estrous cycle, the maximum levels of GV oocytes (26±1/mouse) were isolated from the ovaries of animals injected with the hormone during estrus. The capacity of isolated GV oocytes to meiotic maturation in vitro decreased in the following order: estrus (75.5±2.3%), metestrus (67.9±3.4%), proestrus (57.8±4.4%), and diestrus (50.6±5.6%); the differences between estrus and diestrus/proestrus were significant (p<0.05). After eCG injections during estrus, GV oocytes differed from other oocytes by lesser total diameter, lesser diameter of cytoplasm, lesser thickness of zona pellucida, and moderately dilated perivitelline space. These signs reflected higher competence of the "estrous" GV oocytes for meiotic maturation in vitro. Hormone stimulation of females with eCG, with consideration for the stage of the estrous cycle, seems to be an effective method for improving the quality of GV oocytes isolated from mouse ovaries.


Assuntos
Ciclo Estral/efeitos dos fármacos , Oócitos/citologia , Oócitos/efeitos dos fármacos , Animais , Diestro/efeitos dos fármacos , Estro/efeitos dos fármacos , Feminino , Gonadotropinas/farmacologia , Metestro/efeitos dos fármacos , Camundongos , Ovário/citologia , Ovário/efeitos dos fármacos
3.
Bull Exp Biol Med ; 167(5): 702-705, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31630300

RESUMO

The study examined maturation of preovulatory germinal vesicles oocytes (GV oocytes) induced by gonadotropic hormone PMSG in the inbred C57Bl/6J mice (viewed as a gold standard for diverse biomedical studies) as well as in the first generation hybrid C57Bl/6J×СВА/lac and СВА/lac×C57Bl/6J mice at various ages. The most effective donors of GV oocytes were СВА/lac×C57Bl/6J mice (F1 hybrids) yielding 25±2 oocyte/mouse. In contrast, a significantly smaller number of GV oocytes can be isolated from the ovaries of female C57Bl/6J or C57Bl/6J×СВА/lac mice under the same conditions. At this, the greatest number of GV oocytes (42±4) can be retrieved from the ovaries of immature hybrid СВА/lac×C57Bl/6J mice aged 4 weeks. These mice demonstrated the largest share of GV oocytes, which attained MII stage during in vitro culturing. The data conclude that F1 hybrid СВА/lac×C57Bl/6J mice can be viewed as a handy experimental source yielding a large number of GV oocytes capable of meiotic maturation in a culture.


Assuntos
Fase Folicular/fisiologia , Gonadotropinas Equinas/farmacologia , Meiose , Oócitos/efeitos dos fármacos , Ovário/efeitos dos fármacos , Fatores Etários , Animais , Contagem de Células , Quimera/fisiologia , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Oócitos/citologia , Oócitos/fisiologia , Ovário/citologia , Ovário/fisiologia , Cultura Primária de Células
4.
Gig Sanit ; 95(3): 233-41, 2016.
Artigo em Russo | MEDLINE | ID: mdl-27266021

RESUMO

In the article there are presented data which are the fragment of large multidisciplinary study of genetic safety of non-contact electrochemically activated water (NAW). The aim of this study was the analysis of the relation of impacts of genomic instability (micronucleus test with cytochalasin B) detected in human blood cells, cultured in medias prepared on the base of these NAWs, with physical and chemical properties of these NaWs. In experiments there were used catholytes and anolytes obtained by activation of osmotic, tap and dining bottled water As a result of such activation, all waters were shown to acquire the ability to induce genomic instability in cellular cultures. Notably in cell cultures on catholytes and anolytes these effects differed between themselves and have been associated with different physical and chemical properties of the NAWs.


Assuntos
Água Potável , Técnicas Eletroquímicas/métodos , Monitoramento Ambiental , Instabilidade Genômica/efeitos dos fármacos , Linfócitos , Saúde Pública , Purificação da Água , Água Potável/efeitos adversos , Água Potável/análise , Água Potável/química , Monitoramento Ambiental/métodos , Monitoramento Ambiental/estatística & dados numéricos , Humanos , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Testes para Micronúcleos/métodos , Saúde Pública/métodos , Saúde Pública/estatística & dados numéricos , Federação Russa/epidemiologia , Purificação da Água/métodos , Purificação da Água/normas , Qualidade da Água/normas
5.
Dokl Biochem Biophys ; 467(1): 136-40, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27193718

RESUMO

Using femtosecond laser radiation, nucleolus-like bodies (NLBs) of mouse oocytes were locally dissected without damage to zona pellucida, cytoplasmic membrane, nuclear membrane, and nucleoplasm surrounding NLB. It was found that, after dissection of 2.7 × 10(-11) cm(3) of NLB material, which is approximately 5.2% of 10 µm NLB volume, the probability of germinal vesicle oocyte development to metaphase II stage of meiosis decreased 3-7 times compared to the non-treated oocytes. This result indicates that NLB material organization is significant for mouse oocyte maturation.


Assuntos
Lasers , Oócitos/efeitos da radiação , Oogênese/efeitos da radiação , Animais , Desenho de Equipamento , Meiose/fisiologia , Meiose/efeitos da radiação , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Oócitos/citologia , Oócitos/fisiologia , Oogênese/fisiologia , Fatores de Tempo
6.
Ontogenez ; 47(6): 331-8, 2016.
Artigo em Russo | MEDLINE | ID: mdl-30272883

RESUMO

The mammalian germinal vesicle­stage (GV) oocytes are divided into two major types, NSN (non-surrounded nucleolus) and SN (surrounded nucleolus), and at least one intermediate type, pSN (partly surrounded nucleolus), based on large-scale chromatin configuration. In mice, the SN oocytes are considered to be the most meiotically competent, which explains active study of their phenotypic characteristics necessary for improvement of human reproductive technologies. One of such characteristics is the position of the GV (nucleus) relative to the center of the oocyte. However, the current data on this issue are contradictory and even completely absent for pSN oocytes. In this work, we have studied the GV position in 187 mouse GV oocytes belonging to NSN, SN, and pSN types using different approaches known from the literature. Our results suggest that (1) the most abundant in all examined types of oocytes are central GVs (43­ 66%) and the least abundant are peripheral GVs (12­39%); the pSN oocytes are closer to SN oocytes rather than to NSN oocytes according to the GV position; (3) the position of the nucleus in mouse GV oocytes is an ambiguous marker of large-scale chromatin configuration and, correspondingly, maturation competence of the oocyte; (4) the diversity of the GV position in NSN, SN, and pSN oocytes most likely reflects the ability of GVs to migrate; and (5) assessment of the GV position according to three variants (central, peripheral, and intermediate) is more informative as compared with two variants (central and peripheral).


Assuntos
Cromatina/metabolismo , Oócitos/metabolismo , Animais , Feminino , Camundongos , Oócitos/citologia
7.
Ontogenez ; 46(3): 162-73, 2015.
Artigo em Russo | MEDLINE | ID: mdl-26204768

RESUMO

Postnatal development of mammalian oocytes is accompanied by functional and structural remodeling of the nucleolar apparatus: the final stage of this process is the formation of large objects (up to 10 µm in diameter) termed nucleolus-like bodies (NLBs) in preovulatory GV oocytes. N LB material was shown to be essential for early embryonic development, but its composition is still uncharacterized. In the present study, the protein-binding dye fluorescein-5-isothiocyanate (FITC) was used to show that proteins characterized by a high local concentration are essential NLB components in mouse GV oocytes. One of these proteins was able to be identified for the first time using a mild treatment of oocytes with proteinase K; the protein identified was fibrillarin, a factor of early pre-rRNA processing. Fibrillarin is present in the inner NLB mass of all oocytes capable of synthesizing rRNA; however, it is not colocalized with BrUTP microinjected into oocytes in order to identify transcribed ribosomal genes, in contrast to the "surface" fibrillarin. These observations imply the accumulation of nucleolar proteins not involved in ribosome biogenesis inside the NLB. All NLBs present in an individual nucleus of an NSN-type GV oocyte contain fibrillarin and are associated with active ribosomal genes. The results obtained in the present work demonstrate that proteinase K treatment of GV mouse oocytes allows for: (1) identification of "cryptic" proteins inside the densely packed NLB material and (2) the enhancement of oocyte image quality during BrUTP-based identification of rRNA synthesis sites but (3) not for the detection of active ribosomal genes in the inner mass of the NLB. The fluorescent dye FITC can be recommended for assessment of intracellular protein localization in the oocytes of all mammalian species.


Assuntos
Nucléolo Celular/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Endopeptidase K/química , Oócitos/metabolismo , Precursores de RNA/biossíntese , Transcrição Gênica/fisiologia , Animais , Feminino , Camundongos , Oócitos/citologia
9.
Gig Sanit ; (1): 104-8, 2014.
Artigo em Russo | MEDLINE | ID: mdl-24749297

RESUMO

The dynamic alterations of the magnetic flux density of the water volume, activated with structurally stressed calcium carbonate in micellar form have been investigated. The phase of the associated water was established to exhibit electrical and magnetic properties, recorded by in B&E meter in the frequency range of 5Hz - 2kHz. Alterations in water Eh (redox) potential and the magnetic flux density B testify to synchronous auto-oscillatory changes. This gives evidence of non-linearity of the relationship between auto-oscillatory processes excited in the water; and reflects the nonlocal in time the relationship between the states of water, manifesting in a change of water activity on the 1st and 2nd day in negative time. The mechanism of action of associated water phase is shown to be described by de Broglie concept of matter waves with taking into account delocalized in time states of phase of electron wave packet in accordance with the transactional interpretation of quantum physics.


Assuntos
Carbonato de Cálcio/química , Fenômenos Magnéticos , Teoria Quântica , Água/química , Eletroquímica , Elétrons , Micelas , Fatores de Tempo
10.
Tsitologiia ; 56(7): 489-99, 2014.
Artigo em Russo | MEDLINE | ID: mdl-25696992

RESUMO

The organization and functional activity of the nucleoli of mammalian cells can be modified in response to various stress factors. However, data on the reaction of nucleoli to oxidative stress remain limited. In this paper, we have studied the localization of nucleolar RNAs and two RNA-binding proteins--fibrillarin, a pre-rRNA processing factor, and nucleophosmin/B23, a pre-ribosome assembly factor, in HeLa cells exposed to 1 mM H2O2 up to four hours. We have shown that under the conditions used H2O2 does not induce death, but inhibits rDNA transcription, reduces the total RNA content in the cells and the amount of 18S rRNA in the nucleoli, and causes relocalization of fibrillarin and nucleophosmin/B23 to the nucleoplasm. To date, similar changes in the localization of fibrillarin were described in mammalian cells only after HgCl2 treatment. Redistribution of nucleophosmin/B23 observed in H2O2-treated cells occurred in mammalian cells under inhibition of rDNA transcription and early rRNA processing. Overall, this study shows the high sensitivity of the nucleoli of HeLa cells to acute oxidative stress, which is clearly evident on the cytological level.


Assuntos
Nucléolo Celular/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Proteínas Nucleares/metabolismo , Precursores de RNA/metabolismo , RNA Ribossômico 18S/metabolismo , Proteínas de Ligação a RNA/metabolismo , Movimento Celular , Nucléolo Celular/efeitos dos fármacos , Nucléolo Celular/genética , Proteínas Cromossômicas não Histona/genética , DNA Ribossômico/genética , DNA Ribossômico/metabolismo , Células HeLa , Humanos , Peróxido de Hidrogênio/farmacologia , Cloreto de Mercúrio/toxicidade , Proteínas Nucleares/genética , Nucleofosmina , Estresse Oxidativo , Precursores de RNA/genética , RNA Ribossômico 18S/genética , Proteínas de Ligação a RNA/genética , Transcrição Gênica
11.
Bioorg Khim ; 40(4): 421-32, 2014.
Artigo em Russo | MEDLINE | ID: mdl-25898752

RESUMO

The eukaryotic proteins comprising the SURF6 protein family are evolutionary conservative and housekeeping proteins however, functional roles of human SURF6 have not been studied so far. To shed light to this question in the present work we applied GST pull-down assay and used two proteins fused with GST, namely human GST-SURF6 and the conservative C-terminal domain of mouse Surf6 that has 85% homology with the C-terminus of the human SURF6 conservative domain (GST-Surf6-dom), to identify SURF6-interacting proteins in human HeLa cells. The results obtained showed that GST-SURF6 interacts with several key nucleolar RNA processing factors (B23/nucleophosmin, nucleolin, EBP2), and also with the specific cofactor of RNA polymerase I, protein UBE These results are the first experimental evidences in favor of participation of the human SURF6 protein in ribosome biogenesis, including transcription of rDNA and processing of rRNAs. The same results were obtained, when GST-Surf6-dom was used to pull-down proteins in HeLa cells. In addition, the panel of the GST-Surf6-dom protein partners, which were identified by mass-spectrometry, points to putative interactions of human SURF6 with a number of nuclear and nucleolar, proteins of other functional groups, i.e. to the protein plurifunctionality.


Assuntos
Nucléolo Celular/genética , Proteínas Nucleares/química , RNA Ribossômico/genética , Ribossomos/genética , Animais , Nucléolo Celular/química , DNA Ribossômico/química , DNA Ribossômico/genética , Regulação da Expressão Gênica , Glutationa Transferase/química , Glutationa Transferase/genética , Células HeLa , Humanos , Camundongos , Proteínas Nucleares/genética , Nucleofosmina , Ligação Proteica , RNA Polimerase I/química , RNA Polimerase I/genética , RNA Ribossômico/química , Ribossomos/química
12.
Gig Sanit ; (5): 37-40, 2013.
Artigo em Russo | MEDLINE | ID: mdl-24340908

RESUMO

The results of studies of electrochemical indices of waters activated with structurally stressed calcium carbonate tension in micellar form during storage are presented and these indicators of water were shown to change over time. In this case, waters, having initially superior activity over time reduce it, giving place to the waters that have at this moment an activity greater than the activity of the sample leading at the beginning. Established that the cause of this oscillatory over time change in activity is a non-local interaction between macroscopic quantum systems of activated waters located at a distance from each other. Oscillatory changes of the electrochemical indices of activated water during storage reflect the dynamic of changes in its biological properties. These changes in the electrochemical indices should be considered in evaluation of the structural and energetic state of the activated water during storage by means of introducing the correction factors.


Assuntos
Carbonato de Cálcio/análise , Micelas , Água/química , Eletroquímica , Humanos
13.
Gig Sanit ; (2): 83-7, 2013.
Artigo em Russo | MEDLINE | ID: mdl-24003709

RESUMO

Experimental evidence of the electron-donor ability of drinking water with ion-molecular forms of active oxygen is reported The concentration limits of the content of peroxide ion-radicals (48 mkg /L) in the absence of molecular hydrogen peroxide in drinking water has been determined. The concentration of the peroxide ion-radical in drinking water has been proposed to be used as an index of the water biocatalytic activity.


Assuntos
Água Potável/química , Oxigênio/química , Espécies Reativas de Oxigênio/química , Elétrons , Medições Luminescentes , Peróxidos/química
14.
Bioorg Khim ; 39(3): 326-37, 2013.
Artigo em Russo | MEDLINE | ID: mdl-24397031

RESUMO

Tumor-associated protein survivin is the bifunctional protein which can participate either in cell division regulation or in apoptosis inhibition depending on its localization and structure state. The aim of this work was to obtain monospecific antibodies useful for investigation of protein structure and functional features. Six affinity purified antibodies directed to different protein regions were obtained. The ability of antibodies obtained to detect survivin in tumor cells and breast cancer tissues was studied. It was shown that antibodies to (1-22) and (95-105) survivin fragments have the highest specific activity. In western-blot antibodies to (1-22) region predominantly binds with survivin-containing complex, which may be the survivin dimer as we suppose, while antibodies to (95-105) region detects only monomeric form of the protein. Breast cancer tissues study demonstrated that survivin monomer presents only in the tumor core tissues, while survivin-containing complex is expressed both in tumor core and tumor periphery tissues. It was shown that antibodies to (1-22) fragment detect predominantly nuclear survivin, which participates in mitosis regulation, while antibodies to (95-105) fragment gave nucleoplasm and cytoplasm staining at all stages of cell cycle. Thereby antibodies obtained are the useful tool for structure-functional study of survivin.


Assuntos
Anticorpos/imunologia , Neoplasias da Mama/imunologia , Proteínas Inibidoras de Apoptose/imunologia , Peptídeos/imunologia , Anticorpos/química , Afinidade de Anticorpos/imunologia , Neoplasias da Mama/patologia , Feminino , Células HeLa , Humanos , Proteínas Inibidoras de Apoptose/química , Peptídeos/química , Peptídeos/isolamento & purificação , Survivina
15.
Tsitologiia ; 54(1): 17-24, 2012.
Artigo em Russo | MEDLINE | ID: mdl-22567896

RESUMO

Method FRAP (fluorescence recovery after photobleaching) in combination with confocal laser scanning microscopy represents one of the principal approaches in studying the properties of proteins in living mammal cells. However, the data of different authors on the dynamic properties of the same protein and even in cells of the same type can differ greatly. The reasons of such discrepancies were not specifically analyzed yet. In the present work, on the example of the nucleolar protein fibrillarin fused to EGFP, was studied the impact of area of the region of interest (ROI) and temperature conditions on the main dynamic characteristics of the protein, such as mobile fraction and time for half-time of fluorescence recovery after photobleaching (t1/2). Obtained results suggest that both parameters have a great impact on the estimation of mobile properties of fibrillarin-EGFP in HeLa cells. Was concluded that during FRAP experiments the area of ROI has to be standardized and, as possible, minimized. Moreover, analyzing the dynamic properties of the nucleolar proteins, which take part in the temperature-sensitive reactions, the standard temperature conditions should also be standardized.


Assuntos
Nucléolo Celular/fisiologia , Proteínas Cromossômicas não Histona/análise , Recuperação de Fluorescência Após Fotodegradação/normas , Proteínas de Fluorescência Verde/análise , Proteínas Nucleares/análise , Nucléolo Celular/ultraestrutura , Proteínas Cromossômicas não Histona/genética , Proteínas Cromossômicas não Histona/metabolismo , Recuperação de Fluorescência Após Fotodegradação/métodos , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Meia-Vida , Células HeLa , Humanos , Microscopia Confocal , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fotodegradação , Transporte Proteico/fisiologia , Proteínas Recombinantes de Fusão/análise , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Temperatura
16.
Eur J Histochem ; 55(2): e15, 2011 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-22193295

RESUMO

We have studied by means of ultrastructural immunocytochemistry the localization of RNase A in nuclei of HeLa cells in control conditions and following cell ageing in culture. We have found that roundish, electron dense foci, which contain a significant amount of RNase A, can be detected within nucleoli of aged cells. These bodies also contain RNA and lack ribosomal S3 proteins, and may represent either simple storage sites or areas where RNA degradation takes place.


Assuntos
Nucléolo Celular/enzimologia , Senescência Celular/fisiologia , Ribonuclease Pancreático/metabolismo , Células HeLa , Humanos , RNA/metabolismo , Estabilidade de RNA/fisiologia
17.
Prikl Biokhim Mikrobiol ; 47(2): 141-5, 2011.
Artigo em Russo | MEDLINE | ID: mdl-22808736

RESUMO

cDNA of human gene Surf-6 (hSutf-6) was amplified and cloned into vector pGEX-2T for the expression in the bacterial system of protein hSURF-6 translationally fused to glutathione S-transferase. The resulting vector is named as pGEX-2T-GST-hSurf-6. Superproducer of chimeric protein GST-hSURF-6 was obtained on the basis of Escherichia coli strain BL21-CodonPlus(DE3)-RIL. Its purification was performed by the affinity chromatography on L-glatathione-sepharose. The proportion of recombinant protein GST-hSURF-6 in the optimized conditions was not less than 15% of the total bacterial protein, and up to 7 mg of the protein was isolated from 1 liter of culture of the producer strain. The final fraction of eluate contained approximately 80% of GST-hSURF-6. The amount and the purity of the isolated protein were sufficient to immunize animals and obtain antibodies. Protein GST-hSURF-6 can also be used as an affinity ligand for revealing protein partners of hSURF-6 in human cells.


Assuntos
Escherichia coli/genética , Vetores Genéticos , Proteínas Nucleares/biossíntese , Proteínas Recombinantes de Fusão/biossíntese , Formação de Anticorpos , Western Blotting , Cromatografia de Afinidade , Cromatografia em Agarose , Clonagem Molecular , Eletroforese em Gel de Poliacrilamida , Glutationa Transferase/genética , Células HeLa , Humanos , Proteínas Nucleares/genética , Proteínas Nucleares/isolamento & purificação , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/isolamento & purificação , Análise de Sequência de DNA
18.
Bioorg Khim ; 36(5): 661-71, 2010.
Artigo em Russo | MEDLINE | ID: mdl-21063453

RESUMO

SURF-6 is an evolutionary conserved nucleolar protein that is required for maintenance of cell viability, but its functional significance in mammals still remains illusive. In the present work we examined effects of SURF-6 overexpression in mouse NIH/3T3 fibroblasts transfected with two plasmids. The plasmid pUHrT62-1 encodes a tetracycline-dependant trans-activator, the protein rtTA, the plasmid pBI-SURF6--the genes of EGFP (enhanced green fluorescent protein) and of mouse SURF-6 which expression was controlled by the rtTA-responsive bi-directorial promoter. Western blot analysis showed that the SURF-6 level was severely augmented in cells transfected with pUHrT62-1 and pBI-SURF6 and incubated with the inducer--doxycycline opposed to the transfected but not-induced cells. The increase of SURF-6 was observed in 24 and 48 h after adding the inducer doxycycline. Dot-hybridization of isolated RNA with biotinilated oligonucleotide probes to various regions of mouse primarily pre-rRNA transcripts showed that overexpression of SURF-6 enhanced levels of the second intragenic transcribed spacer ITS2 in about seven folds and of the 5' external transcribed spacer 5'ETS in two folds. Amounts of fragments corresponding to 18S, 5.8S and 28S rRNA remained almost unchanged. These observations for the first time demonstrated that mammalian SURF-6 helps to stabilize or prevents premature cleavage of the pre-rRNA intragenic transcribed spacers, particularly of ITS2, similar to its homologue in S. cerevisiae the protein Rrp14. Today metazoan proteins that play a similar role in ribosome biogenesis, are not described.


Assuntos
Nucléolo Celular/metabolismo , DNA Espaçador Ribossômico/metabolismo , Fibroblastos/metabolismo , Proteínas Nucleares/genética , Precursores de RNA/metabolismo , Processamento Pós-Transcricional do RNA , RNA Ribossômico/metabolismo , Animais , Técnicas de Cultura de Células , Nucléolo Celular/efeitos dos fármacos , Clonagem Molecular , DNA Espaçador Ribossômico/genética , Doxiciclina/farmacologia , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Immunoblotting , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Camundongos , Células NIH 3T3 , Plasmídeos , Precursores de RNA/genética , RNA Ribossômico/genética , Transfecção
19.
Biochemistry (Mosc) ; 75(8): 979-88, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21073418

RESUMO

Fibrillarin is an evolutionarily-conserved and obligatory protein component of eukaryotic cell nucleoli involved in pre-rRNA processing and methylation. In vertebrates the fibrillarin molecule contains two cysteine residues (Cys99 and Cys268) whose sulfhydryl groups are able to establish intramolecular -S-S- bridges. However, the functional state of fibrillarin with reduced or oxidized thiol groups is still practically unstudied. Besides, there are no data in the literature concerning existence of the -S-S- fibrillarin form in human cells. To answer these questions, we used plasmids encoding native human fibrillarin and its mutant form devoid of cysteine residues (fibrillarinC99/268S) fused with EGFP for temporary transfection of HeLa cells. The mobile fraction localizing the enzymatically active protein molecules and the fluorescence half-recovery time characterizing the rate of enzymatic reactions were determined by the FRAP technique using a confocal laser scanning microscope. Measurements were carried out at 37 and 27°C. The results show that the fibrillarin pool in HeLa cells includes two protein forms, with reduced SH groups and with oxidized SH groups forming intramolecular -S-S- bridges between Cys99 and Cys268. However, the absence of Cys99 and Cys268 has no effect on intracellular localization of fibrillarin and its main dynamic parameters. The human fibrillarin form without disulfide bridges is included into the mobile protein fraction and is consistent with its functionally active state.


Assuntos
Proteínas Cromossômicas não Histona/metabolismo , Proteínas Nucleares/metabolismo , Sequência de Aminoácidos , Proteínas Cromossômicas não Histona/química , Cisteína/genética , Cisteína/metabolismo , Células HeLa , Humanos , Imuno-Histoquímica , Dados de Sequência Molecular , Proteínas Nucleares/química , Transfecção
20.
Tsitologiia ; 52(6): 477-86, 2010.
Artigo em Russo | MEDLINE | ID: mdl-20737906

RESUMO

A characteristic feature of systemic autoimmune diseases along with appearance of autoantibodies targeting self-antigenes is deposition of immunoglobulins and components of the complement system in kidneys. However, mechanisms of the deposit formation and their cytotoxic effects still remain poorly studied. To elucidate these questions, we used SJL/J mice which are known to develop autoimmune process accompanied by the appearance of anti-fibrillarin antibodies following regular administrations of sublethal dozes of HgCl2. Using antibodies to the total murine ummunoglobulins we showed that immunodeposits were present in glomeruli of autoimmune and control (not-autoimmune) animals, but their intensity was directly correlated with the titer of anti-fibrillarin autoantibodies and was minimal in control mice. By confocal microscopy and conventional fluorescence microscopy it was defined that immunodeposits deeply penetrate glomeruli and are the most likely located within mesangial cells. In autoimmune animals, ummunoglobulins completely colocolized with the C3--component of complement, but not with the major autoantigen--the protein fibrillarin. We failed to determine the signs of cell proliferation or death in glomeruli. The most prominent difference between control and autoimmune mice was the presence if immunodeposits in renal blood vessels. These observations argue in favor of the idea that destructive and disfunctional renal lesions accompanying development of autoimmune diseases can be caused, in part, by accumulation of immunodeposits in blood vessels.


Assuntos
Complexo Antígeno-Anticorpo/imunologia , Autoanticorpos/imunologia , Doenças Autoimunes/imunologia , Proteínas Cromossômicas não Histona/imunologia , Glomérulos Renais/irrigação sanguínea , Glomérulos Renais/imunologia , Animais , Vasos Sanguíneos/imunologia , Complemento C3/imunologia , Feminino , Glomérulos Renais/efeitos dos fármacos , Cloreto de Mercúrio/toxicidade , Células Mesangiais/efeitos dos fármacos , Células Mesangiais/imunologia , Camundongos , Camundongos Endogâmicos , Microscopia Confocal
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