Nucleolar Organizing Region
Mostrando 1-10 de 10 artigos, teses e dissertações.
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1. Characterization of eight species of Aloe (Asphodelaceae) from the nucleolar organizing region
Resumo A região organizadora nucléica de oito espécies de Aloe foi analisada em metáfases somáticas e núcleos interfásicos. Todas as espécies apresentaram um número uniforme de 2n = 14, com oito cromossomos grandes e seis pequenos. Satélites foram observados no braço longo de um ou dois pares de cromossomos grandes e/ou no braço curto de um dos p
Rodriguésia. Publicado em: 2018-06
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2. Cytomolecular characterization of cultivars and landraces of wheat tolerant and sensitive to aluminum toxicity
ABSTRACT Karyotyping and chromosome complement knowledge are a prerequisite for cytogenetic mapping. The aim of this study was to characterize 1 common wheat cultivar (BH 1146) and 4 durum wheat genotypes (IAC 1003, Langdon, P19 and P33) from the breeding program of the Agronomic Institute of Campinas (IAC), using karyotype analysis together with Chromomycin
Bragantia. Publicado em: 14/08/2017
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3. Physical mapping of the 18S and 5S ribosomal genes in nine Characidae species (Teleostei, Characiformes)
Characidae is one of the largest fish families of the Neotropical region, and presenting a pronounced morphological variability, certainly does not constitute a monophyletic group. The cytogenetical data also show a large chromosomal variation and can provide important information for a better understanding of the relationships between the species of this gr
Genetics and Molecular Biology. Publicado em: 2008
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4. Localization of ribosomal genes in three Pimelodus species (Siluriformes, Pimelodidae) of the São Francisco River: 5S genes as species markers and conservation of the 18S rDNA sites
Pimelodidae is one of the most representative of Neotropical catfish families. However, these fish are still poorly studied in terms of cytogenetics, especially regarding the application of more accurate techniques such as the chromosomal localization of ribosomal genes. In the present work, fluorescent in situ hybridization with 5S and 18S rDNA probes was e
Genetics and Molecular Biology. Publicado em: 2008
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5. Caracterização cromossômica de espécies de acarás da subfamília Cichlasomatinae (Perciformes: Cichlidae) da Amazônia Central
Cytogenetic studies were performed on 13 species of acarás in the family Cichlidae, subfamily Cichlasomatinae, collected from different locations in the Amazon basin. Of these, two exhibited 2n=50, one 2n=42, two 2n=46, and eight 2n=48 chromosomes. Different karyotypic formulae were found in this subfamily, with the number of arms varying from 50 to 60. Thi
Publicado em: 2006
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6. Chromosomal banding patterns in the eyelid-less microteiid lizard radiation: The X1X1X2X2:X1X2Y sex chromosome system in Calyptommatus and the karyotypes of Psilophthalmus and Tretioscincus (Squamata, Gymnophthalmidae)
Cytogenetic studies were performed on five closely related microteiid lizards (Gymnophthalmini), three Calyptommatus species and Psilophthalmus paeminosus from the sand dunes of the middle São Francisco river in the semiarid caatinga of the Brazilian state of Bahia and Tretioscincus oriximinensis from the Brazilian Amazon region. The diploid chromosome numb
Genetics and Molecular Biology. Publicado em: 2005-12
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7. Citogenetica comparativa de especies de aplastodiscus e do grupo de Hyla albomarginata (Hylidae, Anura) / Comparative cytogenetics of aplastodiscus species and Hyla albomarginata group (Hylidae, Anura)
The Hylidae family includes four subfamilies, with Hylinae comprising 27 genera. The Hyla genus has many species divided into related groups. The Hyla albomarginata group, as known as "green Hylas" is subdivided into 3 complexes: "albomarginata","albosignata" and "albofrenata". The Aplastodiscus genus has been the object oftaxonomic discussion since its desc
Publicado em: 2005
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8. Multiple pericentric inversions and chromosomal divergence in the reef fishes Stegastes (Perciformes, Pomacentridae)
Damselfishes (Pomacentridae, Perciformes) occur in all major oceans of the world and, with approximately 320 species, represent one of the most diverse families of marine Teleostei. The taxonomy of these reef fishes is problematic because of the large number of complex species and the range of color patterns they display, which vary among individuals and pop
Genetics and Molecular Biology. Publicado em: 2004
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9. Molecular structure of a wheat chromosome end healed after gametocidal gene-induced breakage
In the progeny of the monosomic addition line of common wheat, Triticum aestivum, carrying the gametocidal chromosome of Aegilops cylindrica, deletion chromosomes carrying the break point within the nucleolar organizing region of chromosome 1B appeared. Attempts were made to amplify the break points by PCR using primers of telomere and rDNA (rRNA gene). In o
The National Academy of Sciences of the USA.
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10. Analysis of Nondisjunction Induced by the R-X1 Deficiency during Microsporogenesis in Zea Mays L
The r-X1 deficiency in maize induces nondisjunction at the second mitotic division during embryo sac formation. However, it was not known if this deficiency also induces nondisjunction during the microspore divisions. Microsporogenesis in plants lacking or containing this deficiency was compared using two approaches. First, chromosome numbers were determined