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  1 / 6823 MEDLINE  
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[PMID]:28007046
[Au] Autor:Wasielak M; Wiesak T; Bogacka I; Jalali BM; Bogacki M
[Ad] Endereço:Department of Gamete and Embryo Biology,Institute of Animal Reproduction and Food Research of the Polish Academy of Sciences,Tuwima 10,10-747 Olsztyn,Poland.
[Ti] Título:Maternal effect gene expression in porcine metaphase II oocytes and embryos in vitro: effect of epidermal growth factor, interleukin-1ß and leukemia inhibitory factor.
[So] Source:Zygote;25(2):120-130, 2017 Apr.
[Is] ISSN:1469-8730
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Maternal effect genes (MEG) play a crucial role in early embryogenesis. In vitro culture conditions may affect MEG expression in porcine oocytes and embryos. We investigated whether in vitro culture medium supplementation with epidermal growth factor (EGF), IL-1ß or LIF (leukemia inhibitory factor) affects the mRNA level of ZAR-1 (zygote arrest 1), NPM2 (nucleoplasmin 2) and DPPA3 (developmental associated protein 3) in porcine MII oocytes and embryos. Cumulus-oocyte complexes (COCs) were matured in NCSU-37 medium (control) or in NCSU-37 with EGF 10 ng/ml, IL-1ß 10 ng/ml or LIF 50 ng/ml. After maturation for 44-46 h, MII oocytes were preserved for the analysis of MEG mRNA levels (experiment 1). In experiment 2, COCs were fertilized, and the presumptive zygotes were cultured in the same groups. Then, 2-, 4-, 8-cell embryos, morulae and blastocysts were collected for the analysis of MEG mRNA levels. LIF addition to the maturation medium increased MII oocyte numbers (P < 0.05), while EGF and IL-1ß did not affect oocyte maturation. Medium supplementation with EGF resulted in lower DPPA3 mRNA levels in MII oocytes and in 2- and 4-cell embryos versus control embryos (P < 0.05). LIF treatment increased DPPA3 mRNA levels in morulae and blastocysts (P < 0.05). Culture with EGF and IL-1ß decreased ZAR-1 and NPM2 mRNA levels in 2-cell embryos (P < 0.05). The inclusion of EGF or IL-1ß in the porcine in vitro production system influences ZAR-1, NPM2 and DPPA3 mRNA in MII oocytes and embryos but not beyond the 4-cell stage. LIF stimulates oocyte maturation and affects DPPA3 mRNA in porcine morulae and blastocysts in vitro.
[Mh] Termos MeSH primário: Proteínas do Ovo/metabolismo
Embrião de Mamíferos/metabolismo
Fator de Crescimento Epidérmico/farmacologia
Interleucina-1beta/farmacologia
Fator Inibidor de Leucemia/farmacologia
Metáfase/fisiologia
Oócitos/metabolismo
[Mh] Termos MeSH secundário: Animais
Proteínas do Ovo/genética
Embrião de Mamíferos/citologia
Embrião de Mamíferos/efeitos de drogas
Desenvolvimento Embrionário/efeitos de drogas
Feminino
Fertilização In Vitro/veterinária
Fármacos Gastrointestinais/farmacologia
Regulação da Expressão Gênica/efeitos de drogas
Técnicas In Vitro
Metáfase/efeitos de drogas
Nucleoplasminas/metabolismo
Oócitos/citologia
Oócitos/efeitos de drogas
Suínos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Egg Proteins); 0 (Gastrointestinal Agents); 0 (Interleukin-1beta); 0 (Leukemia Inhibitory Factor); 0 (Nucleoplasmins); 62229-50-9 (Epidermal Growth Factor)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171031
[Lr] Data última revisão:
171031
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161223
[St] Status:MEDLINE
[do] DOI:10.1017/S0967199416000332


  2 / 6823 MEDLINE  
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[PMID]:29017027
[Au] Autor:Vukusic K; Buda R; Bosilj A; Milas A; Pavin N; Tolic IM
[Ad] Endereço:Division of Molecular Biology, Ruder Boskovic Institute, Bijenicka cesta 54, 10000 Zagreb, Croatia.
[Ti] Título:Microtubule Sliding within the Bridging Fiber Pushes Kinetochore Fibers Apart to Segregate Chromosomes.
[So] Source:Dev Cell;43(1):11-23.e6, 2017 Oct 09.
[Is] ISSN:1878-1551
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:During cell division, mitotic spindle microtubules segregate chromosomes by exerting forces on kinetochores. What forces drive chromosome segregation in anaphase remains a central question. The current model for anaphase in human cells includes shortening of kinetochore fibers and separation of spindle poles. Both processes require kinetochores to be linked with the poles. Here we show, by combining laser ablation, photoactivation, and theoretical modeling, that kinetochores can separate without any attachment to one spindle pole. This separation requires the bridging fiber, a microtubule bundle that connects sister kinetochore fibers. Bridging fiber microtubules in intact spindles slide apart with kinetochore fibers, indicating strong crosslinks between them. We conclude that sliding of microtubules within the bridging fibers drives pole separation and pushes kinetochore fibers poleward by the friction of passive crosslinks between these fibers. Thus, sliding within the bridging fiber works together with the shortening of kinetochore fibers to segregate chromosomes.
[Mh] Termos MeSH primário: Anáfase/fisiologia
Segregação de Cromossomos/fisiologia
Cinetocoros/metabolismo
Metáfase/fisiologia
Microtúbulos/metabolismo
[Mh] Termos MeSH secundário: Células Cultivadas
Humanos
Modelos Biológicos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171023
[Lr] Data última revisão:
171023
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171010
[St] Status:MEDLINE


  3 / 6823 MEDLINE  
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[PMID]:28810257
[Au] Autor:Wang GX; He QY; Macas J; Novák P; Neumann P; Meng DX; Zhao H; Guo N; Han S; Zong M; Jin WW; Liu F
[Ad] Endereço:Beijing Vegetable Research Center, Beijing Academy of Agriculture and Forestry Sciences, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (North China), Ministry of Agriculture, Beijing Key Laboratory of Vegetable Germplasm Improvement, Beijing, China.
[Ti] Título:Karyotypes and Distribution of Tandem Repeat Sequences in Brassica nigra Determined by Fluorescence in situ Hybridization.
[So] Source:Cytogenet Genome Res;152(3):158-165, 2017.
[Is] ISSN:1424-859X
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:Whole-genome shotgun reads were analyzed to determine the repeat sequence composition in the genome of black mustard, Brassica nigra (L.) Koch. The analysis showed that satellite DNA sequences are very abundant in the black mustard genome. The distribution pattern of 7 new tandem repeats (BnSAT13, BnSAT28, BnSAT68, BnSAT76, BnSAT114, BnSAT180, and BnSAT200) on black mustard chromosomes was visualized using fluorescence in situ hybridization (FISH). The FISH signals of BnSAT13 and BnSAT76 provided useful cytogenetic markers; their position and fluorescence intensity allowed for unambiguous identification of all 8 somatic metaphase chromosomes. A karyotype showing the location and fluorescence intensity of these tandem repeat sequences together with the position of rDNAs and centromeric retrotransposons of Brassica (CRB) was constructed. The establishment of the FISH-based karyotype in B. nigra provides valuable information that can be used in detailed analyses of B. nigra accessions and derived allopolyploid Brassica species containing the B genome.
[Mh] Termos MeSH primário: DNA de Plantas/genética
Hibridização in Situ Fluorescente/métodos
Cariótipo
Mostardeira/genética
Sequências de Repetição em Tandem/genética
[Mh] Termos MeSH secundário: Centrômero
Cromossomos de Plantas/genética
Cromossomos de Plantas/ultraestrutura
DNA Ribossômico/genética
DNA Satélite/genética
Marcadores Genéticos
Genoma de Planta
Metáfase
Microscopia de Fluorescência
Retroelementos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Plant); 0 (DNA, Ribosomal); 0 (DNA, Satellite); 0 (Genetic Markers); 0 (Retroelements)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171020
[Lr] Data última revisão:
171020
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170815
[St] Status:MEDLINE
[do] DOI:10.1159/000479179


  4 / 6823 MEDLINE  
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[PMID]:28333241
[Au] Autor:Dal Canto M; Guglielmo MC; Mignini Renzini M; Fadini R; Moutier C; Merola M; De Ponti E; Coticchio G
[Ad] Endereço:Biogenesi Reproductive Medicine Centre, Istituti Clinici Zucchi, Via Zucchi, Monza,Italy.
[Ti] Título:Dysmorphic patterns are associated with cytoskeletal alterations in human oocytes.
[So] Source:Hum Reprod;32(4):750-757, 2017 04 01.
[Is] ISSN:1460-2350
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Study question: Are specific morphological anomalies in human mature oocytes, as revealed by transmitted light microscopy, associated with intrinsic damage to the meiotic spindle and actin cytoskeleton? Summary answer: Aggregates of smooth endoplasmic reticulum (SER) and domains of centrally localized granular cytoplasm (GC) reflect intrinsic damage to the oocyte cytoskeleton, namely alterations in spindle size, chromosome misalignment and cortical actin disorganization. What is known already: In preparation for ICSI, oocytes are often selected for use in treatment by morphological criteria, but the rationale and implications of this practice are controversial. Very little information is available on the relationship between oocyte morphology and intrinsic cellular characteristics, such as the actin cytoskeleton, meiotic spindle and chromosome alignment. Study design, size, duration: A total of 170 metaphase II (MII) oocytes were donated by consenting IVF patients and analysed; 62 were classified as morphologically normal (control), 54 had SER clusters and 54 had centrally localized GC. Participants/materials, setting, methods: Supernumerary oocytes were fixed within 3 h from recovery and stained for tubulin, chromatin and actin. Spindles were analysed for 1D and 2D characteristics by high-performance confocal microscopy. Chromosomes were classified as scattered or aligned and the conformation and intensity of cortical actin was evaluated. Main results and the role of chance: In comparison with control oocytes, both SER and GC oocytes showed greater spindle length (P = 0.033 and 0.003, respectively) and GC oocytes also showed greater spindle width (P= 0.049) and area (P= 0.036). Control and SER oocytes had statistically comparable rates of chromosome displacement from the metaphase plate, unlike GC oocytes where chromosome displacement occurred at higher rate (P = 0.013). In situations where a complete Z-stack was reconstructed from a polar angle, chromosome disposition was classified as being normal when two sets of concentric arrays were visible. Based on these parameters, the proportions of oocytes with normal chromosomal arrangement or partial/total disarrangement was not statistically different between control and SER oocytes. Conversely, in GC oocytes, chromosome disarrangement was higher (P = 0.002). All control oocytes displayed a continuous meshwork of suboolemmal actin, which appeared as an uninterrupted ring in thin optical sections. In contrast, in SER and  GC groups, integrity of suboolemmal actin was observed in only 66.7 and 42.9% of oocytes, respectively (P = 0.0001). Large scale data: N/A. Limitations reason for caution: Only two of several known oocyte dysmorphisms were investigated, while oocyte quality was assessed only by cytoskeletal criteria. Wider implications of the findings: This study represents a significant step toward a more objective assessment of oocyte morphology, offering information that can assist embryologists to make a more aware and rationally founded decision on whether, and with what possible implications, oocytes with certain dysmorphic characters should be used for treatment or discarded. More generally, it also demonstrates that morphometric parameters of the cytoskeleton and chromosome organization can be used as biomarkers of oocyte quality. Study funding and competing interest(s): This study was funded by Biogenesi Reproductive Medicine Centre (Monza, Italy). All authors declare no conflict of interests.
[Mh] Termos MeSH primário: Citoesqueleto/ultraestrutura
Oócitos/ultraestrutura
Fuso Acromático/ultraestrutura
[Mh] Termos MeSH secundário: Biomarcadores
Cromossomos/ultraestrutura
Citoplasma/ultraestrutura
Retículo Endoplasmático Liso/ultraestrutura
Feminino
Humanos
Técnicas de Maturação in Vitro de Oócitos
Metáfase
Oócitos/citologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Biomarkers)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171017
[Lr] Data última revisão:
171017
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170323
[St] Status:MEDLINE
[do] DOI:10.1093/humrep/dex041


  5 / 6823 MEDLINE  
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[PMID]:28402514
[Au] Autor:Novák P; Ávila Robledillo L; Koblízková A; Vrbová I; Neumann P; Macas J
[Ad] Endereço:Institute of Plant Molecular Biology, Biology Centre CAS, Ceské Budejovice CZ-37005, Czech Republic.
[Ti] Título:TAREAN: a computational tool for identification and characterization of satellite DNA from unassembled short reads.
[So] Source:Nucleic Acids Res;45(12):e111, 2017 Jul 07.
[Is] ISSN:1362-4962
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Satellite DNA is one of the major classes of repetitive DNA, characterized by tandemly arranged repeat copies that form contiguous arrays up to megabases in length. This type of genomic organization makes satellite DNA difficult to assemble, which hampers characterization of satellite sequences by computational analysis of genomic contigs. Here, we present tandem repeat analyzer (TAREAN), a novel computational pipeline that circumvents this problem by detecting satellite repeats directly from unassembled short reads. The pipeline first employs graph-based sequence clustering to identify groups of reads that represent repetitive elements. Putative satellite repeats are subsequently detected by the presence of circular structures in their cluster graphs. Consensus sequences of repeat monomers are then reconstructed from the most frequent k-mers obtained by decomposing read sequences from corresponding clusters. The pipeline performance was successfully validated by analyzing low-pass genome sequencing data from five plant species where satellite DNA was previously experimentally characterized. Moreover, novel satellite repeats were predicted for the genome of Vicia faba and three of these repeats were verified by detecting their sequences on metaphase chromosomes using fluorescence in situ hybridization.
[Mh] Termos MeSH primário: Mapeamento Cromossômico/métodos
DNA de Plantas/genética
DNA Satélite/genética
Genoma de Planta
Software
[Mh] Termos MeSH secundário: Angiospermas/genética
Sequência de Bases
Análise por Conglomerados
Gráficos por Computador
Sequência Consenso
Cyperaceae/genética
DNA Satélite/classificação
Hibridização in Situ Fluorescente
Metáfase
Ervilhas/genética
Análise de Sequência de DNA
Vicia faba/genética
Zea mays/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Plant); 0 (DNA, Satellite)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171011
[Lr] Data última revisão:
171011
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170412
[St] Status:MEDLINE
[do] DOI:10.1093/nar/gkx257


  6 / 6823 MEDLINE  
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[PMID]:28588079
[Au] Autor:Moriggi G; Gaspar SG; Nieto B; Bustelo XR; Dosil M
[Ad] Endereço:Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer, CSIC-University of Salamanca, 37007 Salamanca, Spain.
[Ti] Título:Focal accumulation of preribosomes outside the nucleolus during metaphase-anaphase in budding yeast.
[So] Source:RNA;23(9):1432-1443, 2017 Sep.
[Is] ISSN:1469-9001
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:contains one nucleolus that remains intact in the mother-cell side of the nucleus throughout most of mitosis. Based on this, it is assumed that the bulk of ribosome production during cell division occurs in the mother cell. Here, we show that the ribosome synthesis machinery localizes not only in the nucleolus but also at a center that is present in the bud side of the nucleus after the initiation of mitosis. This center can be visualized by live microscopy as a punctate body located in close proximity to the nuclear envelope and opposite to the nucleolus. It contains ribosomal DNA (rDNA) and precursors of both 40S and 60S ribosomal subunits. Proteins that actively participate in ribosome synthesis, but not functionally defective variants, accumulate in that site. The formation of this body occurs in the metaphase-to-anaphase transition when discrete regions of rDNA occasionally exit the nucleolus and move into the bud. Collectively, our data unveil the existence of a previously unknown mechanism for preribosome accumulation at the nuclear periphery in budding yeast. We propose that this might be a strategy to expedite the delivery of ribosomes to the growing bud.
[Mh] Termos MeSH primário: Anáfase
Nucléolo Celular/genética
Nucléolo Celular/metabolismo
Metáfase
Saccharomycetales/genética
Saccharomycetales/metabolismo
[Mh] Termos MeSH secundário: Transporte Biológico
Pontos de Checagem do Ciclo Celular/genética
DNA Ribossômico/genética
DNA Ribossômico/metabolismo
Expressão Gênica
Genes Reporter
Espaço Intracelular/metabolismo
RNA Ribossômico/genética
RNA Ribossômico/metabolismo
Ribossomos/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Ribosomal); 0 (RNA, Ribosomal)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171009
[Lr] Data última revisão:
171009
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170607
[St] Status:MEDLINE
[do] DOI:10.1261/rna.061259.117


  7 / 6823 MEDLINE  
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[PMID]:28738367
[Au] Autor:Colomina V; Catalan J; Britton-Davidian J; Veyrunes F
[Ad] Endereço:Institut des Sciences de l'Evolution (ISEM), UMR 5554, CNRS/Université Montpellier/IRD/EPHE, Montpellier, France.
[Ti] Título:Extensive Amplification of Telomeric Repeats in the Karyotypically Highly Diverse African Pygmy Mice.
[So] Source:Cytogenet Genome Res;152(2):55-64, 2017.
[Is] ISSN:1424-859X
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:Telomeres are ribonucleoprotein structures protecting the physical ends of eukaryotic chromosomes. However, telomeric sequences can also occur at non-terminal regions of chromosomes, forming the so-called interstitial telomeric sequences (ITSs). Some ITSs are considered as relics of past chromosomal rearrangements and as such provide important insights into karyotype evolution. By FISH, we explored the distribution of telomeric motifs in the genome of a complex of mammalian species that has long been recognized for its extraordinary karyotypic diversity: the African pygmy mice. This survey involved 5 species, representing 10 highly diverse karyotypes with or without autosomal and sex-autosome robertsonian (Rb) fusions. The study revealed that in species with an ancestral-like karyotype (i.e., no fusions; Mus mattheyi and M. indutus), only terminal telomeres were observed, whereas in species experiencing intense chromosomal evolution (e.g., M. minutoides, M. musculoides), a large amplification of telomeric repeats was also identified in the pericentromeric region of acrocentrics and most metacentrics. We concluded that (i) the mechanism of Rb fusion in the African pygmy mice is different than the one highlighted in the house mouse; (ii) the intensity of the ITS hybridization signal could be a signature of the age of formation of the Rb fusion; (iii) the large amplification of pericentromeric telomeric sequences in acrocentrics may mediate the formation of Rb fusions, and (iv) the ITSs on the sex-autosome fusion Rb(X.1) may participate to the insulation buffer between the sexual and autosomal arms to prevent X inactivation from spreading and silencing autosomal genes and allow the independent regulation of replication timing of both segments.
[Mh] Termos MeSH primário: Amplificação de Genes
Cariótipo
Sequências Repetitivas de Ácido Nucleico/genética
Telômero/genética
[Mh] Termos MeSH secundário: Animais
Sequência de Bases
Feminino
Hibridização in Situ Fluorescente
Masculino
Metáfase/genética
Camundongos
Filogenia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170929
[Lr] Data última revisão:
170929
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170724
[St] Status:MEDLINE
[do] DOI:10.1159/000478297


  8 / 6823 MEDLINE  
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[PMID]:28719910
[Au] Autor:Bustamante FO; Aliyeva-Schnorr L; Fuchs J; Beier S; Houben A
[Ad] Endereço:Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, Seeland, Germany.
[Ti] Título:Correlating the Genetic and Physical Map of Barley Chromosome 3H Revealed Limitations of the FISH-Based Mapping of Nearby Single-Copy Probes Caused by the Dynamic Structure of Metaphase Chromosomes.
[So] Source:Cytogenet Genome Res;152(2):90-96, 2017.
[Is] ISSN:1424-859X
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:Genetic maps are based on the recombination frequency of molecular markers which often show different positions in comparison to the corresponding physical maps. To decipher the position and order of DNA sequences genetically mapped to terminal and interstitial regions of barley (Hordeum vulgare) chromosome 3H, fluorescence in situ hybridization (FISH) on mitotic metaphase chromosomes was performed with 16 genomic single-copy probes derived from fingerprinted BAC contigs. Long genetic distances at subterminal regions translated into short physical distances, confirming that recombination events occur more often at distal regions of chromosome 3H. Nonoverlapping FISH signals were frequently obtained for probes with a physical distance of at least 30-60 kb. Only 8% of the analyzed chromosomes showed a symmetric order of FISH signals on both sister chromatids. Due to the dynamic packing of metaphase chromatin, the order of 2 adjacent single-copy signals along the chromosome arms outside the (peri)centromeric region can only reliably be determined if the cytological distance is approximately 3%, corresponding to 21.6 Mb.
[Mh] Termos MeSH primário: Mapeamento Cromossômico/métodos
Cromossomos de Plantas/genética
Dosagem de Genes
Hordeum/genética
Hibridização in Situ Fluorescente/métodos
Metáfase/genética
Mapeamento Físico do Cromossomo/métodos
[Mh] Termos MeSH secundário: Pareamento de Bases/genética
Cromátides/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170929
[Lr] Data última revisão:
170929
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170718
[St] Status:MEDLINE
[do] DOI:10.1159/000478631


  9 / 6823 MEDLINE  
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[PMID]:28564645
[Au] Autor:Galkina S; Fillon V; Saifitdinova A; Daks A; Kulak M; Dyomin A; Koshel E; Gaginskaya ER
[Ad] Endereço:Biological Faculty, Saint Petersburg State University, Saint Petersburg, Russia.
[Ti] Título:Chicken Microchromosomes in the Lampbrush Phase: A Cytogenetic Description.
[So] Source:Cytogenet Genome Res;152(1):46-54, 2017.
[Is] ISSN:1424-859X
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:Lampbrush chromosomes are giant, transcriptionally active, meiotic chromosomes found in oocytes of all vertebrates with the exception of mammals. Lampbrush chromosomes offer a convenient tool for cytogenetic mapping and, in particular, have been instrumental in mapping genes and linkage groups on chicken (GGA) chromosomes. Whereas cytogenetic maps of macrochromosome GGA1-10 and microchromosome GGA11-16 lampbrush bivalents have been established, identification and description of smaller microchromosome bivalents are still missing. In this work, we used specific FISH probes for the identification of 12 chicken lampbrush chromosomes formed by GGA17-28. Our observations on chromomere and lateral loop arrangement and chiasma position allowed us to construct the respective cytogenetic maps for these microchromosomes. For the 10 smallest chicken microchromosomes, GGA29-38, no individual molecular tags are available, yet they can be collectively marked using the PO41 repeat. The reported results contribute to building of working cytogenetic maps of the chicken karyotype.
[Mh] Termos MeSH primário: Galinhas/genética
Cromossomos/genética
Citogenética/métodos
[Mh] Termos MeSH secundário: Animais
Cromossomos Artificiais Bacterianos/genética
Metáfase/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170929
[Lr] Data última revisão:
170929
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170531
[St] Status:MEDLINE
[do] DOI:10.1159/000475563


  10 / 6823 MEDLINE  
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[PMID]:28514774
[Au] Autor:Schmid M; Steinlein C; Lomb C; Volleth M
[Ad] Endereço:Department of Human Genetics, University of Würzburg, Würzburg, Germany.
[Ti] Título:Demonstration of 5-Methylcytosine-Rich DNA Sequences in Chiroptera.
[So] Source:Cytogenet Genome Res;152(1):38-45, 2017.
[Is] ISSN:1424-859X
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:5-Methylcytosine-rich heterochromatic regions were demonstrated in metaphase chromosomes of 5 species of Chiroptera by indirect immunofluorescence using a monoclonal anti-5-methylcytosine antibody. These species belong to 4 genera and 2 families and are characterized by divergent karyotypes. One species (Glauconycteris beatrix) has an extremely low diploid chromosome number of 2n = 22 with only meta- to submetacentric elements and remarkably large amounts of constitutive heterochromatin located in the centromeric and pericentromeric regions of all chromosome pairs. Two species (G. beatrix and Neoromicia cf. guineensis) possess X-autosome translocations. In all species, the hypermethylated chromosome segments correspond to constitutive heterochromatin, and the numbers and positions of hypermethylated chromosome segments in the karyotypes are constant and species-specific. In some species (Pipistrellus hesperidus, Neoromicia cf. somalicus), there are several smaller chromosome pairs in which the bright anti-5-methylcytosine antibody labeling is not restricted to constitutively heterochromatic regions but is observed along the whole lengths of these chromosomes. The nature of these additional hypermethylated regions is discussed. The analysis of 5-methylcytosine-rich chromosome regions elucidates valuable data for chiropteran cytogenetics and reflects the high pace of evolution of the repetitive DNA fraction in their genomes.
[Mh] Termos MeSH primário: 5-Metilcitosina/metabolismo
Quirópteros/genética
[Mh] Termos MeSH secundário: Animais
Sequência de Bases
Metilação de DNA/genética
Feminino
Imunofluorescência
Cariótipo
Cariotipagem
Masculino
Metáfase
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
6R795CQT4H (5-Methylcytosine)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170929
[Lr] Data última revisão:
170929
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170517
[St] Status:MEDLINE
[do] DOI:10.1159/000475740



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