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Pesquisa : A11.284.430.106.279.345.175 [Categoria DeCS]
Referências encontradas : 15 [refinar]
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Id: lil-676823
Autor: Leonova, Olga G; Karajan, Bella P; Ivlev, Yuri F; Ivanova, Julia L; Skarlato, Sergei O; Popenko, Vladimir I.
Título: Quantitative analysis of nucleolar chromatin distribution in the complex convoluted nucleoli of Didinium nasutum (Ciliophora)
Fonte: Biol. Res;46(1):69-74, 2013. ilus, tab.
Idioma: en.
Projeto: Russian Foundation for Basic Research.
Resumo: We have earlier shown that the typical Didinium nasutum nucleolus is a complex convoluted branched domain, comprising a dense fibrillar component located at the periphery of the nucleolus and a granular component located in the central part. Here our main interest was to study quantitatively the spatial distribution of nucleolar chromatin structures in these convoluted nucleoli. There are no "classical" fibrillar centers in D.nasutum nucleoli. The spatial distribution of nucleolar chromatin bodies, which play the role of nucleolar organizers in the macronucleus of D.nasutum, was studied using 3D reconstructions based on serial ultrathin sections. The relative number of nucleolar chromatin bodies was determined in macronuclei of recently fed, starved D.nasutum cells and in resting cysts. This parameter is shown to correlate with the activity of the nucleolus. However, the relative number of nucleolar chromatin bodies in different regions of the same convoluted nucleolus is approximately the same. This finding suggests equal activity in different parts of the nucleolar domain and indicates the existence of some molecular mechanism enabling it to synchronize this activity in D. nasutum nucleoli. Our data show that D. nasutum nucleoli display bipartite structure. All nucleolar chromatin bodies are shown to be located outside of nucleoli, at the periphery of the fibrillar component.
Descritores: Nucléolo Celular/ultraestrutura
Cromatina/metabolismo
Cilióforos/citologia
-Nucléolo Celular/metabolismo
Cromatina/ultraestrutura
Cilióforos/metabolismo
Microscopia Eletrônica de Varredura
Região Organizadora do Nucléolo/metabolismo
Tipo de Publ: Research Support, Non-U.S. Gov't
Revisão
Responsável: CL1.1 - Biblioteca Central


  2 / 15 LILACS  
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Id: lil-595026
Autor: Liu, Donghua; Jiang, Wusheng; Meng, Qingmin; Zou, Jin; Gu, Jiegang; Zeng, Muai.
Título: Cytogenetical and ultrastructural effects of copper on root meristem cells of Allium sativum L
Fonte: Biocell;33(1):25-32, Apr. 2009. ilus, tab.
Idioma: en.
Resumo: Different copper concentrations, as well as different exposure times, were applied to investigate both cytogenetical and ultrastructural alterations in garlic (Allium sativum L.) meristem cells. Results showed that the mitotic index decreased progressively when either copper concentration or exposure time increased. C-mitosis, anaphase bridges, chromosome stickiness and broken nuclei were observed in the copper treated root tip cells. Some particulates containing the argyrophilic NOR-associated proteins were distributed in the nucleus of the root-tip cells and the amount of this particulate material progressively increased with increasing exposure time. Finally, the nucleolar material was extruded from the nucleus into the cytoplasm. Also, increased dictyosome vesicles in number, formation of cytoplasmic vesicles containing electron dense granules, altered mitochondrial shape, disruption of nuclear membranes, condensation of chromatin material, disintegration of organelles were observed. The mechanisms of detoxification and tolerance of copper are briefly discussed.
Descritores: Aberrações Cromossômicas/classificação
Allium
Allium/genética
Cobre/toxicidade
Meristema
Meristema/genética
Raízes de Plantas
Raízes de Plantas/genética
-Citoplasma
Citoplasma/ultraestrutura
Mitose
Mitose/genética
Núcleo Celular
Núcleo Celular/ultraestrutura
Nucléolo Celular
Nucléolo Celular/ultraestrutura
Tipo de Publ: Research Support, Non-U.S. Gov't
Responsável: AR40.1 - Biblioteca de la Facultad de Ciencias Médicas de la UNCuyo


  3 / 15 LILACS  
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Cruz-Landim, C
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Id: lil-569173
Autor: Cruz-Landim, C; Patrício, K.
Título: Nuclear activity in Apis mellifera L. (Hymenoptera, Apidae) queen ovary cells demonstrated by silver nitrate impregnation and ultrastructure / Atividade nuclear em células do ovário de rainha de Apis mellifera L. (Hymenoptera, Apidae) demonstrada por impregnação com nitrato de prata e ultraestrutura
Fonte: Braz. j. biol;70(4):1069-1073, Nov. 2010. ilus.
Idioma: en.
Resumo: The present paper shows through conventional light microscopy, silver nitrate impregnation and Transmission Electron Microscopy, the changes in nuclear activity that occurs in the ovary cells during vitellogenesis of Apis mellifera (Linnaeus, 1758). The material impregnated by silver nitrate was detected in nurse cells, oocyte germinal vesicle and follicular cells, whose amounts are greater in phases corresponding to ovarian cells more intense activity. The silver impregnation permitted to demonstrate that the oocyte germinal vesicle synthezises ribonucleoproteins (RNP) during the beginning of the vitellogenesis. The ultrastructure show nucleolar-like material corresponding to nuclear sites impregnated by silver.

Este estudo mostra, por meio de microscopia convencional, impregnação por nitrato de prata e microscopia eletrônica de transmissão, as mudanças que ocorrem na atividade nuclear de células do ovário durante a vitelogênese de Apis mellifera (Linnaeus, 1758). Material impregnado por nitrato de prata foi detectado no núcleo de células nutridoras, na vesícula germinal do ovócito e no núcleo das células foliculares. As maiores quantidades de material impregnado pela prata foram observadas durante as fases de maior atividade dessas estruturas. A impregnação por prata permitiu demonstrar que a vesícula germinal sintetiza ribonucleoproteínas (RNP) durante o início da vitelogênese. A ultraestrutura mostrou que o material impregnado apresenta características morfológicas de nucléolos.
Descritores: Abelhas/ultraestrutura
Nucléolo Celular/ultraestrutura
Ovário/ultraestrutura
Vitelogênese/fisiologia
-Abelhas/fisiologia
Microscopia Eletrônica de Transmissão
Ovário/fisiologia
Nitrato de Prata
Coloração pela Prata
Limites: Animais
Feminino
Tipo de Publ: Research Support, Non-U.S. Gov't
Responsável: BR1.1 - BIREME


  4 / 15 LILACS  
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Id: lil-565385
Autor: Cornejo U., Ricardo.
Título: Morfometría del nucleolo en la diferenciación celular del epitelio mamario / Nucleolus morphometry in the cellular differentiation of mammary epithelium
Fonte: Rev. chil. obstet. ginecol;75(2):107-111, 2010. ilus, graf, tab.
Idioma: es.
Resumo: Antecedentes: El proceso biológico de diferenciación celular es la traducción de múltiples procesos nucleares y citoplasmáticos que determinan cambios complejos y fundamentales en la ultraestructura, bioquímica y fsiología celular, los cuales pueden ser cuantifcados mediante técnicas morfométricas. Objetivo: Evidenciar en términos cuantitativos y morfológicos las variaciones experimentadas por los nucleolos pertenecientes a células mamarias de la línea HC11 tanto normales como en mecanismo de diferenciación. Método: Se estudió a nivel de la microscopía electrónica de transmisión los tipos celulares en etapa de proliferación (HC11 GM) en comparación con células en estadio de diferenciación (HC11 IM), cuantifcando las variaciones de los nucleolos y su relación con estructuras involucradas en síntesis proteica. Resultados: Se evidencian diferencias estadísticamente signifcativas referentes al área, volumen y longitud entre los nucleolos pertenecientes al tipo celular normal-proliferante y el que se encuentra en proceso de diferenciación. Conclusión: Las células mamarias en proceso de diferenciación presentan una notable disminución de sus nucleolos, y sus ribonucleoproteínas constitutivas generarán básicamente ribosomas adheridos al retículo endoplasmático rugoso, sintetizando proteínas de exportación.

Background: The biological process of cell differentiation is the traslation of multiple nuclear and cytoplas-mic processes that determine complex and fundamental changes in ultrastructure, biochemistry and cell physiology, which can be quantifed using morphometric techniques. Objective: To show in quantitative and morphological terms changes experienced by the nucleolus belonging to HC11 line mammary cells both, in proliferating and differentiation process. Methods: A study at the level of transmission electron microscopy of cell types in stage of cell proliferation in comparison with stage of differentiation was designed to quantify variations of nucleolus and their relation to structures involved in protein synthesis. Results: Marked differences in the area, volume and length of the nucleolus were found between normal-proliferating cell types and those in mechanism of differentiation. Conclusion: The mammary cells in differentiation process show a dramatic decline in its nucleoli and their ribonucleoproteins generate basically ribosomes attached at endo-plasmic reticulum, synthesizing export proteins.
Descritores: Células Epiteliais/ultraestrutura
Diferenciação Celular/fisiologia
Glândulas Mamárias Humanas/ultraestrutura
Nucléolo Celular/ultraestrutura
-Glândulas Mamárias Humanas/citologia
Microscopia Eletrônica
Proliferação Celular
Limites: Seres Humanos
Responsável: CL1.1 - Biblioteca Central


  5 / 15 LILACS  
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Id: lil-553788
Autor: Aarestrup, J. R; Karam, D; Fernandes, G. W.
Título: Chromosome number and cytogenetics of Euphorbia heterophylla L
Fonte: Genet. mol. res. (Online);7(1):217-222, Jan. 2008. ilus.
Idioma: en.
Resumo: Euphorbia heterophylla L. (Euphorbiaceae) is a herbaceous species of great economic importance due to its invasive potential and consequent damage to agriculture and pasture land. For the first time, we provide information on its chromosome number, morphology, and behavior of mitotic chromosomes. Seeds were germinated and submitted to four treatments to obtain metaphases: 0.5% colchicine for 2 to 5 h, at ambient temperature; 0.5% colchicine for 16 to 24 h; 0.0029 M 8-hydroxyquinoline (8-HQ) for 2 to 5 h at ambient temperature, and 0.0029 M 8-HQ for 16 to 24 h at 4°C. The material was then fixed in methanol:acetic acid (3:1) and kept at -20°C for 24 h. Roots were macerated in the enzyme solution of Flaxzyme™ (NOVO FERMENT™)-distilled water (1:40) at 34°C for 2 h and later fixed again. Chromosome preparations were obtained by the dissociation of the apical meristems. The best chromosome preparations were obtained with the use of 8-HQ for 21 h 30 min at 4°C. E. heterophylla showed 2n = 28 chromosomes. The short arm of the largest pair of chromosomes of the complement (pair number 1) displayed a secondary constriction while the nucleolus was observed in the interphasic cell. Structural rearrangements were also observed in the E. heterophylla L. genome. The genomic instability associated with polyploidy may be the result of selection shaped by environmental adaptations and/or human-induced manipulation through agricultural practices.
Descritores: Cromossomos de Plantas
Análise Citogenética
Euphorbia/genética
-Agricultura
Nucléolo Celular
Instabilidade Genômica
Metáfase
Mitose
Poliploidia
Raízes de Plantas/citologia
Raízes de Plantas/genética
Responsável: BR26.1 - Biblioteca Central


  6 / 15 LILACS  
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Id: lil-520050
Autor: Peruquetti, R. L.
Título: Analysis of the nucleolar cycle in the seminiferous epithelium of rodents
Fonte: Genet. mol. res. (Online);6(4):1012-1012, 2007.
Idioma: en.
Resumo: The nucleolus is a subcompartment of the nucleus and the site of ribosome biogenesis. During the mitotic and meiotic cell cycles, a disorganization and later reorganization of the nucleolar material occur, an event called nucleologenesis. In the spermatogenesis of mammals and other vertebrates, there is evidence of the disorganization of the nucleolus at the end of meiosis I, which supplies material for the cytoplasmic formation of an organelle called the “chromatoid body” (CB). The CB is a structure characteristic of spermatogenic cells and seems to be responsible for RNA metabolism in these cells and for some events of spermiogenesis, such as the formation of the acrosome, cellular communication between spermatids, and the formation of the spermatozoon middle piece and tail. The aim of this paper was to obtain information about the cytochemical and ultrastructural nature of the nucleolar cycle and the distribution of cytoplasmic RNAs in the seminiferous tubule cells of Rattus novergiucus, Mus musculus and Meriones unguiculatus. The testis was fixed in Bouin and Karnovsky solutions for conventional histological analysis and for cytochemical study that included: periodic acid-Schiff, hematoxylin-eosin, Feulgen reaction, silver-ion impregnation, Gomori's reticulin stain, toluidine blue, modified method of critical electrolyte concentration, and basic and acid fast green. The blocks of testis fixed in glutaraldehyde were used for ultrastructural analysis by transmission electron microscopy. Ultrathin sections were double-stained with uranyl acetate and lead citrate. All the techniques used provided information on the origin and function of the CB in the spermatogenic cells. Therefore, considering the persistence of the RNA and nucleolar ribonucleoproteins during spermatogenesis of Rattus novergicus, Mus musculus and Meriones unguiculatus, our findings corroborate the statement that these molecular complexes are very important in the spermiogenesis phases...
Descritores: Epitélio Seminífero/fisiologia
Nucléolo Celular/fisiologia
Roedores/genética
-Epitélio Seminífero/ultraestrutura
Espermatogênese/fisiologia
Nucléolo Celular/ultraestrutura
Proteínas Nucleares/metabolismo
RNA
Limites: Animais
Masculino
Responsável: BR26.1 - Biblioteca Central


  7 / 15 LILACS  
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Cassali, G. D
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Id: lil-500072
Autor: Souza, P. C; Ocarino, N. M; Tavares, W. L. F; Boeloni, J. N; Cassali, G. D; Serakides, R.
Título: Association of nucleolar organizing regions and Ki-67 expression with recurrence rate of hair follicle tumor in dogs / Associação das regiões organizadoras de nucléolos e da expressão do Ki-67 com a taxa de recorrência dos tumores de folículo piloso em cães
Fonte: Arq. bras. med. vet. zootec;60(5):1075-1083, out. 2008. ilus, tab.
Idioma: en.
Resumo: Mitotic index, nuclear diameter, number of nucleolar organizing regions, and Ki-67 expression, in hair follicle tumors of 82 dogs were evaluated. Tissue specimens were used to prepare sections for histological staining for number of nucleolar organizing region and immunohistochemical staining for Ki-67. Tumors were classified as trichoblastoma (n=32), benign trichoepithelioma (n=30), pilomatricoma (n=7), malignant trichoepithelioma (n=6), infundibular keratinizing acanthoma (n=5), and tricholemmoma (n=2). Head, dorsum, and limbs were the most affected sites. Malignant trichoepithelioma presented significantly higher mitotic index, number of nucleolar organizing regions and Ki-67 expression. Regarding benign neoplasms, trichoblastoma presented significantly higher mitotic index and number of nucleolar organizing regions. Ki-67 expression did not differ among hair follicle benign neoplasms. Recurrence was only observed in two cases, with one benign trichoepithelioma and one malignant trichoepithelioma. In the two cases, nodules have not been removed with clean surgical margin. It was concluded that in benign neoplasms of hair follicles, the number of nucleolar organizing regions and Ki-67 expression were significantly smaller than in malignant neoplasm. Clean surgical margins are suggested to be more responsible to tumor recurrences than the number of nucleolar organizing regions, expression of Ki-67, and the mitotic index.

O objetivo deste trabalho foi avaliar o índice mitótico, o diâmetro nuclear, o número de regiões organizadoras de nucléolos e a expressão do Ki-67 em 82 tumores de folículo piloso de cães, entre 2000 e 2006. Os tumores foram classificados como tricoblastoma (n=32), tricoepitelioma benigno (n=30), tricoepitelioma maligno (n=6), pilomatricoma (n=7), acantoma infundibular ceratinizante (n=5) e tricolemoma (n=2). A cabeça, o dorso e os membros foram os locais mais frequentemente acometidos. O tricoepitelioma maligno apresentou índice mitótico, número de regiões organizadoras de nucléolos e expressão do Ki-67 significativamente maiores quando comparado aos outros tipos de tumores. Dentre as neoplasias benignas, o tricoblastoma apresentou índice mitótico e número de regiões organizadoras de nucléolos significativamente maiores. A expressão do Ki-67 não diferiu entre os tumores benignos de folículo piloso. A recorrência foi observada apenas em dois casos, incluindo um tricoepitelioma benigno e um tricoepitelioma maligno. Em dois casos, os nódulos não foram removidos com margem cirúrgica completa. Desta forma, conclui-se que nas neoplasias benignas de folículo piloso, o número das regiões organizadoras de nucléolo e da expressão de Ki-67 foram significativamente menores que em neoplasias malignas. Além disto, sugere-se que a margem cirúrgica completa está mais associada à recorrência dos tumores que as regiões organizadoras de nucléolo, a expressão de Ki-67 e o índice mitótico.
Descritores: /metabolismo
ANTIGENO KI-ABDOMEN, ACUTEABDOMINAL INJURIES/metabolismo
Cães
Folículo Piloso/patologia
Folículo Piloso/ultraestrutura
Neoplasias/ultraestrutura
Nucléolo Celular/metabolismo
Limites: Animais
Responsável: BR68.1 - Biblioteca Virginie Buff D'Ápice


  8 / 15 LILACS  
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Ramalho, Luciana Maria Pedreira
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Id: lil-499891
Autor: Freitas, Maria da Conceição Andrade de; Ramalho, Luciana Maria Pedreira; Xavier, Flávia Caló Aquino; Moreira, André Luis Gomes; Reis, Sílvia Regina Almeida.
Título: p53 and MDM2 protein expression in actinic cheilitis
Fonte: J. appl. oral sci;16(6):414-419, Nov.-Dec. 2008. ilus, tab.
Idioma: en.
Resumo: Actinic cheilitis is a potentially malignant lip lesion caused by excessive and prolonged exposure to ultraviolet radiation, which can lead to histomorphological alterations indicative of abnormal cell differentiation. In this pathology, varying degrees of epithelial dysplasia may be found. There are few published studies regarding the p53 and MDM2 proteins in actinic cheilitis. Fifty-eight cases diagnosed with actinic cheilitis were histologically evaluated using Banóczy and Csiba (1976) parameters, and were subjected to immunohistochemical analysis using the streptavidin-biotin method in order to assess p53 and MDM2 protein expression. All studied cases expressed p53 proteins in basal and suprabasal layers. In the basal layer, the nuclei testing positive for p53 were stained intensely, while in the suprabasal layer, cells with slightly stained nuclei were predominant. All cases also tested positive for the MDM2 protein, but with varying degrees of nuclear expression and a predominance of slightly stained cells. A statistically significant correlation between the percentage of p53 and MDM2-positive cells was established, regardless of the degree of epithelial dysplasia. The expression of p53 and MDM2 proteins in actinic cheilitis can be an important indicator in lip carcinogenesis, regardless of the degree of epithelial dysplasia.
Descritores: Queilite/patologia
/análise
PROTO-ONCOGENE PROTEINS C-MDMTEMEFOS/análise
/análise
TUMOR SUPPRESSOR PROTEIN PDIPETALONEMA INFECTIONS/análise
-Biomarcadores/análise
Adesão Celular/genética
Diferenciação Celular/genética
Nucléolo Celular/ultraestrutura
Núcleo Celular/ultraestrutura
Polaridade Celular/genética
Queilite/genética
Cromatina/ultraestrutura
Citoplasma/ultraestrutura
Células Epiteliais/patologia
Epitélio/patologia
Hiperplasia
Imuno-Histoquímica
Queratinas
Lábio/patologia
Mitose/genética
Luz Solar/efeitos adversos
Limites: Seres Humanos
Tipo de Publ: Estudo Comparativo
Responsável: BR1.1 - BIREME


  9 / 15 LILACS  
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Id: lil-482092
Autor: Oliveira, C. I; Bicudo, H. E; Itoyama, M. M.
Título: New evidence for nucleolar dominance in hybrids of Drosophila arizonae and Drosophila mulleri
Fonte: Genet. mol. res. (Online);5(4):632-637, 2006. ilus.
Idioma: en.
Resumo: Drosophila mulleri (MU) and D. arizonae (AR) are cryptic species of the mulleri complex, mulleri subgroup, repleta group. Earlier cytogenetic studies revealed that these species have different regulatory mechanisms of nucleolar organizing activity. In these species, nucleolar organizing regions are found in both the X chromosome and the microchromosome. In the salivary glands of hybrids between MU females and AR males, there is an interspecific dominance of the regulatory system of the D. arizonae nucleolar organizer involving, in males, amplification and activation of the nucleolar organizer from the microchromosome. The authors who reported these findings obtained hybrids only in that cross-direction. More recently, hybrids in the opposite direction, i.e., between MU males and AR females, have been obtained. The purpose of the present study was to evaluate, in these hybrids, the association of the nucleoli with the chromosomes inherited from parental species in order to cytogenetically confirm the dominance patterns previously described. Our results support the proposed dominance of the AR nucleolar organizer activity over that of MU, regardless of cross-direction.
Descritores: Cromossomo X/genética
Drosophila/genética
Hibridização Genética/genética
Nucléolo Celular/genética
Região Organizadora do Nucléolo/genética
-Cruzamentos Genéticos
Variação Genética
Padrões de Herança/genética
Limites: Animais
Feminino
Masculino
Tipo de Publ: Research Support, Non-U.S. Gov't
Responsável: BR1.1 - BIREME


  10 / 15 LILACS  
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Id: lil-480621
Autor: Rosete, María; Padrós, María Rosa; Vindrola, Osvaldo.
Título: El nucléolo como un regulador del envejecimiento celular / The nucleolus as a regulator of cellular senescence
Fonte: Medicina (B.Aires);67(2):183-194, 2007. ilus.
Idioma: es.
Projeto: CONACYT.
Resumo: El nucléolo, considerado únicamente como el sitio de síntesis de los ribosomas, actualmente representa una estructura nuclear dinámica que participa en la regulación de importantes procesos celulares. Numerosas evidencias han demostrado que el envejecimiento celular es una de las diversas funciones que son controladas por el nucléolo. Las mutaciones en las proteínas de localización nucleolar promueven el envejecimiento prematuro en levaduras y humanos. La carencia de represión en la transcripción de genes que codifican para el ARNr que se encuentran dañados, y las mutaciones en las helicasas del ADN encargadas de minimizar la formación de círculos extra-cromosómicos del ADN que codifica para el ARNr, provocan modificaciones en la estructura del nucléolo e inducen envejecimiento prematuro en levaduras. De igual manera, en los humanos la carencia de las helicasas del ADN localizadas en el nucléolo y que participan en el mantenimiento de la integridad genómica, favorecen el desarrollo de aquellas enfermedades asociadas con el envejecimiento acelerado. Además, la presencia de algunos componentes de la telomerasa en el nucléolo, indica que parte de la biosíntesis de esta enzima se realiza en esta estructura nuclear, sugiriendo una conexión entre el nucléolo y la síntesis de los telómeros en la regulación del envejecimiento celular. Por otra parte, el nucléolo secuestra proteínas para regular su actividad biológica durante el inicio o término de la vida replicativa celular.

The nucleolus has been considered originally only as the site for the ribosome synthesis, but now it is well known that it represents a dynamic nuclear structure involved in important cellular processes. Several evidences have demonstrated that the nucleolus regulates the cellular senescence. Specific mutations on the DNAs codifying for nucleolar proteins induced premature senescence from yeast to human. The failure to repress the genes transcription codifying for damaged rRNA, and the mutations in DNA helicases, which minimizes the formation of DNA extra-chromosomal circles codifying for rRNA, modify the nucleolar structure and induce premature senescence in yeast. Similarly, in humans, the reduction of these DNA helicases levels, which are localized in the nucleoli and participate in maintenance of genomic integrity, helps to the development of those diseases associated with premature senescence. Furthermore, the presence in the nucleolus of some telomerase components, indicates that part of the biosynthesis of this enzyme occurred in this nuclear structure; suggesting a communication between the nucleolus and the synthesis of the telomeres in the regulation of cell senescence. On the other hand, the nucleolus sequesters proteins to regulate its own biological activity, from the start to the end of cellular replication. In addition this nuclear structure is involved in the biosynthesis of most cellular ribonucleoprotein particles, as well as in cell cycle regulation, making it central to gene expression. In conclusion, the nucleolus became a multifunctional subnuclear structure involved from cell proliferation to cell senescence.
Descritores: Senescência Celular/fisiologia
Nucléolo Celular/fisiologia
/fisiologia
TUMOR SUPPRESSOR PROTEIN PDIPETALONEMA INFECTIONS/fisiologia
Síndrome de Werner/genética
-Dano ao DNA/fisiologia
DNA Helicases/fisiologia
Genes de RNAr/fisiologia
Telômero/fisiologia
Limites: Seres Humanos
Tipo de Publ: Revisão
Responsável: BR1.1 - BIREME



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