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| Registros recuperados: 34 | |
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| Fregonezi,Jéferson N.; Torezan,José M.D.; Vanzela,André L.L.. |
| The Asteraceae, one of the largest families of flowering plants, contains about 1,100 genera and 20,000 species, and is well known for its extensive karyotypic variation. In this study, conventional Feulgen staining, C-CMA3 banding, and fluorescence in situ hybridization with a 45S rDNA probe were used to determine the chromosome number and the number and physical position of GC-rich heterochromatin and 45S rDNA sites in three Asteraceae weed species (Crepis japonica, Galinsoga parviflora and Chaptalia nutans). The three species exhibited karyotype differences in the chromosome number and shape, as a commom feature of Asteraceae. However, the 45S rDNA sites always occurred on the short chromosomal arms, associated with GC-heterochromatin. Althought of... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: CMA3; FISH; Heterochromatin; Polyploidy; 45S rDNA. |
| Ano: 2004 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572004000200016 |
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| Moreira,Camila Nascimento; Di-Nizo,Camilla Bruno; Silva,Maria José de Jesus; Yonenaga-Yassuda,Yatiyo; Ventura,Karen. |
| Pseudoryzomys simplex, the false rice rat, is a monotypic genus of the Oryzomyini tribe (Sigmodontinae) distributed in part of Bolivia, Paraguay, Argentina and Brazil. Its diploid number has been described as 56 acrocentric chromosomes decreasing in size and no karyotype figure has been depicted. Herein, we present karyotypic data on P. simplex, including chromosome banding and molecular fluorescent in situ hybridization using telomeric sequences and the whole X-chromosome of its sister clade Holochilus brasiliensis (HBR) as probes. A case of remarkable autosomal heteromorphism due to the presence of a whole heterochromatic arm leading to the variability of FN is reported, as well as the occurrence of regions of homology between the X and Y chromosomes... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cytogenetics; Fluorescent in situ hybridization; Heterochromatin; Oryzomyini. |
| Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572013000200010 |
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| Bione,Edgar; Camparoto,Marjori Leiva; Simões,Zilá Luz Paulino. |
| Meiotic and mitotic chromosomes of Isocopris inhiata and Diabroctis mimas were studied by standard staining procedures, C-banding, silver nitrate staining and FISH using Apis mellifera 28S rDNA as probe. Isocopris inhiata presented a 2n = 18 (8II+ Xy p) karyotype, composed of meta-submetacentric chromosomes with gradual reduction in size. The karyotype of D. mimas was 2n = 20 (9II+ Xy p), composed of meta-submetacentric (pairs 1, 2, 3, 4 and 7) and acrocentric (pairs 5, 6, 8 and 9) chromosomes, with gradual reduction in size. Analysis of constitutive heterochromatin revealed similar C-banding patterns for both species, showing pericentromeric and telomeric bands and diphasic chromosomes. In addition, the X chromosomes of these species were found to be... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Coleoptera; Heterochromatin; NORs; FISH. |
| Ano: 2005 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572005000100019 |
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| Dantas,Liliane G.; Guerra,Marcelo. |
| A comparative analysis of mitotic chromosomes of Theobroma cacao (cacao) and T. grandiflorum (cupuaçu) was performed aiming to identify cytological differences between the two most important species of this genus. Both species have symmetric karyotypes, with 2n = 20 metacentric chromosomes ranging in size from 2.00 to 1.19 µm (cacao) and from 2.21 to 1.15 mm (cupuaçu). The interphase nuclei of both species were of the arreticulate type, displaying up to 20 chromocentres, which were more regularly shaped in cacao than in cupuaçu. Prophase chromosomes of both species were more condensed in the proximal region, sometimes including the whole short arm. Both species exhibited only one pair of terminal heterochromatic bands, positively stained with chromomycin... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cacao; Cupuaçu; Heterochromatin; Karyotype; RDNA sites; Theobroma. |
| Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572010000100017 |
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| Nirchio,Mauro; Masache,Maria Cecilia; Paim,Fabilene Gomes; Cioffi,Marcelo de Bello; Moreira Filho,Orlando; Barriga,Ramiro; Oliveira,Claudio; Rossi,Anna Rita. |
| ABSTRACT Parodontidae is a relatively small group of Neotropical characiform fishes consisting of three genera (Apareiodon, Parodon, and Saccodon) with 32 valid species. A vast cytogenetic literature is available on Apareiodon and Parodon, but to date, there is no cytogenetic data about Saccodon, a genus that contains only three species with a trans-Andean distribution. In the present study the karyotype of S. wagneri was described, based on both conventional (Giemsa staining, Ag-NOR, C-bands) and molecular (repetitive DNA mapping by fluorescent in situ hybridization) methods. A diploid chromosome number of 2n = 54 was observed in both sexes, and the presence of heteromorphic sex chromosomes of the ZZ/ZW type was detected. The W chromosome has a terminal... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Ag-NOR; Cytogenetics; FISH; Heterochromatin; ZW sex chromosomes. |
| Ano: 2021 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252021000100203 |
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| Chiarini,Franco E; Gauthier,Martha J. |
| The chromosomes of Solanum nelsonii, S. sandwicense (endemic to the Hawaii islands) and S. vespertilio (from the Canary islands) were studied by means of classical staining, CMA/DAPI banding and FISH with probes for the 18-5.8-26S and 5S rDNA genes. The aim of this study was to test for chromosomal changes (chromosome number, karyotype, heterochromatin pattern, rDNA loci) during the evolution of these taxa with respect to their continental relatives. An apparent chromosome stasis was confirmed in all three species, in regards to chromosome number and karyotype morphology. However, there was also evidence of cryptic, cumulative sequence changes. Speciation in these species is not likely associated with large, obvious chromosome rearrangements or polyploidy,... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chromosome stasis; Heterochromatin; Ribosomal DNA; Solanum subgen; Leptostemonum. |
| Ano: 2016 |
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S1851-23722016000200009 |
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| Cunha,Marina Souza da; Travenzoli,Natália Martins; Ferreira,Riudo de Paiva; Cassinela,Edson Kuatelela; Silva,Henrique Barbosa da; Oliveira,Francisco Plácido Magalhães; Salomão,Tânia Maria Fernandes; Lopes,Denilce Meneses. |
| Abstract The genus Melipona is subdivided into four subgenera based on morphological characteristics, and two groups based on cytogenetic patterns. The cytogenetic information on this genus is still scarce, therefore, the goal of this study was to characterize Melipona paraensis, Melipona puncticollis, and Melipona seminigra pernigra using the following techniques: C-banding, DAPI/CMA3 fluorochromes, and FISH with an 18S rDNA probe. Melipona paraensis (2n=18) and M. seminigra pernigra (2n=22) were classified as high heterochromatin content species (Group II). Their euchromatin is restricted to the ends of the chromosomes and is CMA3+; the 18S rDNA probe marked chromosome pair number 4. Melipona puncticollis (2n=18) is a low heterochromatin content species... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chromosomal evolution; DAPI/CMA3 fluorochromes; Fluorescent in situ Hybridization (FISH); Heterochromatin; Meliponini. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572018000500806 |
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| Silva,Guilherme Messias da; Bione,Edgar Guimarães; Cabral-de-Mello,Diogo Cavalcanti; Moura,Rita de Cássia de; Simões,Zilá Luz Paulino; Souza,Maria José de. |
| Meiotic and mitotic chromosomes of Dichotomius nisus, D. semisquamosus and D. sericeus were analyzed after conventional staining, C-banding and silver nitrate staining. In addition, Dichotomius nisus and D. semisquamosus chromosomes were also analyzed after fluorescent in situ hybridization (FISH) with an rDNA probe. The species analyzed had an asymmetrical karyotype with 2n = 18 and meta-submetacentric chromosomes. The sex determination mechanism was of the Xy p type in D. nisus and D. semisquamosus and of the Xyr type in D. sericeus. C-banding revealed the presence of pericentromeric blocks of constitutive heterochromatin (CH) in all the chromosomes of the three species. After silver staining, the nucleolar organizer regions (NORs) were located in... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chromosome rearrangements; Heterochromatin; Karyotype; NORs; FISH. |
| Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572009000200012 |
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| Rubert,Marceléia; Zawadzki,Cláudio H.; Giuliano-Caetano,Lucia. |
| Hypostomus is the most speciose genus in the family Loricariidae, with approximately 120 species. These fish show a wide morphological and color variation, which hinders the identification of species, mainly of widely distributed representatives. The aim of this study was to contribute to the current knowledge on cytogenetic features of Hypostomus nigromaculatus. Three specimens of H. nigromaculatus, collected in two tributaries of rio Tibagi, Paraná, and in Cachoeira de Emas, rio Mogi-Guaçu, São Paulo, the latter being the type locality of H. nigromaculatus, were studied. Chromosomal preparations were submitted to Giemsa staining, silver nitrate impregnation, C-banding and CMA3 and DAPI fluorochromes staining. All samples presented 2n = 76, but the rio... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Karyotype evolution; Nucleolus organizer region; Heterochromatin; Hypostominae. |
| Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252008000100011 |
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| Nogueira,Lídia; Zanoni,Juliani Bruna; Solé,Mirco; Affonso,Paulo Roberto Antunes de Mello; Siqueira,Sérgio; Sampaio,Iracilda. |
| Scinax species are still underrepresented in cytogenetic studies, mainly with respect to populations from northeastern and northern Brazil. In this study, we provide new chromosomal information on Scinax boesemani, S. camposseabrai, S. garbei, S. pachycrus, S. trilineatus and S. x-signatus, all belonging to clade S. ruber. They were collected at two locations in the Caatinga biome (northeastern Brazil) and at one in the Amazon (northern Brazil) biomes. Chromosomes were analyzed by conventional staining, C-banding, Ag-NOR staining, and fluorochrome staining. All species shared a modal diploid value of 2n = 24 and fundamental arm number (FN) of 48. Moreover, both chromosomal size and morphology were similar to other species in this Scinax clade. C-banding... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Amphibians; Chromosomes; Fluorochromes; Heterochromatin; RDNA. |
| Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572015000200156 |
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| Treco,Fernando Rodrigo; Malabarba,Luiz R.; Giuliano-Caetano,Lucia; Dias,Ana Lúcia. |
| A cytogenetic study was conducted on specimens of Parapimelodus nigribarbis and Pimelodus maculatus collected in the lago Guaíba drainage, Porto Alegre, Rio Grande do Sul, Brazil. The two species had a diploid number of 56 chromosomes, with P. nigribarbis showing a karyotype of 20m + 20sm + 4st + 12a with FN of 100, and P. maculatus showing a karyotype of 24m + 20sm + 6st + 6a with FN of 106. NORs were demonstrated in both species in only one pair of subtelocentric chromosomes, in the terminal region of the long arm, which was coincident with C- banding and CMA3 staining, while DAPI staining was negative in these regions. Parapimelodus nigribarbis had a greater number of heterochromatic bands than did P. maculatus, which were distributed mainly in the... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Parapimelodus; Pimelodus; NOR; Heterochromatin; Fluorochromes. |
| Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252008000100010 |
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| Registros recuperados: 34 | |
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