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Registros recuperados: 16 | |
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Schneider,Marielle Cristina; Carraro,Bianca Pierina; Cella,Doralice Maria; Matiello,Rodrigo Rodrigues; Artoni,Roberto Ferreira; Almeida,Mara Cristina. |
In this work we describe the cytogenetic analyses performed in specimens of Astylus variegatus (Germar, 1824) collected in two localities: one area of natural vegetation and one of agricultural crops, where agrochemical products were used. Astylus variegatus had karyotypes with 2n(male) = 16+Xy p and 2n (female) = 16+XXp, with exclusively metacentric chromosomes. Pachytene spermatocytes showed synapsed autosomal bivalents and non-associated sex chromosomes. In diplotene, the autosomal bivalents exhibited one or two terminal chiasmata and the Xy p had a typical parachute configuration. In meiotic cells of some specimens, an extra chromosome, interpreted as a B chromosome, was observed. C-banding showed constitutive heterochromatin in the pericentromeric... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: B chromosome; Constitutive heterochromatin; Karyotype; Meiosis; Ag-NORs. |
Ano: 2007 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572007000400023 |
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Kantek,Daniel Luis Zanella; Cipriano,Roger Raupp; Noleto,Rafael Bueno; Fenocchio,Alberto Sergio; Artoni,Roberto Ferreira; Cestari,Marta Margarete. |
Chromosomal analyses were performed in the fish Astyanax sp.D collected from three different points: two streams from the right bank and one from the left bank of the Upper Iguaçu River, Paraná State, Brazil. The individuals from all localities possess 2n = 50 chromosomes and a FN = 84 (4m+24sm+6st+16a). The C-banding pattern was similar in all populations. However, within each population, an interindividual variation concerning the number and localization of heterochromatic bands was observed. Some of these variations were quantified in each population, and the results indicate that the samples were not different when studying the variable frequencies. Considering that Astyanax sp.D is typical in the headwaters of the Iguaçu River, these results were not... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Population cytogenetics; Chromosome variations; Astyanax fish. |
Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572008000200013 |
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Mendes-Neto,Ernani de Oliveira; Vicari,Marcelo Ricardo; Campaner,Carlos; Nogaroto,Viviane; Artoni,Roberto Ferreira; Almeida,Mara Cristina. |
Cytogenetic analysis of Astylus antis using mitotic and meiotic cells was performed to characterize the haploid and diploid numbers, sex determination system, chromosome morphology, constitutive heterochromatin distribution pattern and chromosomes carrying nucleolus organizer regions (NORs). Analysis of spermatogonial metaphase cells revealed the diploid number 2n = 18, with mostly metacentric chromosomes. Metaphase I cells exhibited 2n = 8II+Xyp and a parachute configuration of the sex chromosomes. Spermatogonial metaphase cells submitted to C-banding showed the presence of small dots of constitutive heterochromatin in the centromeric regions of nearly all the autosomes and on the short arm of the X chromosome (Xp), as well as an additional band on one of... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Sex chromosomes; Meiosis; Metaphase; FISH; 18S rDNA. |
Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572010000200007 |
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Artoni,Roberto Ferreira; Molina,Wagner Franco; Bertollo,Luis Antonio Carlos; Galetti Junior,Pedro Manoel. |
The chromosomes of two neotropical freshwater fish species, namely Liposarcus anisitsi (Siluriformes, Loricariidae) and Leporinus elongatus (Characiformes, Anostomidae), were investigated by means of C-banding, Ag-NORs, fluorochrome staining and banding by hot saline solution (HSS) treatment, to reveal patterns of heterochromatin differentiation. The karyotype of L. anisitsi is described for the first time. Staining with the GC-specific fluorescent antibiotic mithramycin (MM) revealed bright signals in some C-banded blocks in both species, suggesting that these MM+ heterochromatin contains GC-rich DNA. Banding by denaturation employing HSS, followed by Giemsa staining, yielded corresponding results documenting the thermal stability of GC-rich DNA part of... |
Tipo: Info:eu-repo/semantics/article |
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Ano: 1999 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47571999000100009 |
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Gross,Maria Claudia; Schneider,Carlos Henrique; Matiello,Mara Cristina de Almeida; Leite,Maysa de Lima; Bertollo,Luiz Antonio Carlos; Artoni,Roberto Ferreira. |
Morphological and chromosomal markers were used to infer the structure and genetic variability of a population of fish of the genus Astyanax, geographically isolated at sinkhole 2 of Vila Velha State Park, Paraná, Brazil. Two morphotypes types were observed, the standard phenotype I and phenotype II which showed an anatomical alteration probably due to an inbreeding process. Fluctuating asymmetry (FA) analysis of different characters showed low levels of morphological variation among the population from sinkhole 2 and in another population from the Tibagi river (Paraná, Brazil). The Astyanax karyotype was characterized in terms of chromosomal morphology, constitutive heterochromatin and nucleolar organizer regions. Males and females presented similar... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Fish; Astyanax sp.; Fluctuating asymmetry; Karyotype structure; Triploidy; Genetic conservation. |
Ano: 2004 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572004000400011 |
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Vicari,Marcelo Ricardo; Almeida,Mara Cristina de; Bertollo,Luiz Antonio Carlos; Moreira-Filho,Orlando; Artoni,Roberto Ferreira. |
We used differential staining techniques (BSG, GTG, AgNO3, DAPI and CMA3 banding) and fluorescent in situ hybridization (FISH) with 5S and 18S probes to investigated the karyotypic and cytogenetic chracteristics of Prochilodus lineatus specimens from a population in Vila Velha state park (Parque Estadual de Vila Velha, Ponta Grossa, Paraná state, southern Brazil). The specimens studied showed the same karyotype as that found in other P. lineatus populations, i.e. 2n = 54 biarmed chromosomes (40m + 14 sm) and c-positive heterochromatin preferentially located pericentromerically in all chromosomes. The presence of partial or totally heterochromatic supernumerary chromosomes with numeric intra-individual variation was confirmed in the analyzed population. The... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Fish cytogenetics; Prochilodus; Karyotype; Minor and major rDNA; NOR polymorphism. |
Ano: 2006 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572006000400008 |
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Vicari,Marcelo Ricardo; Artoni,Roberto Ferreira; Bertollo,Luiz Antonio Carlos. |
The chromosomes of specimens from four Hoplias malabaricus populations from headwaters of adjacent river basins at Ponta Grossa, southern Brazil, were investigated using differential staining techniques (C-banding, AgNO3 and CMA3) and fluorescent in situ hybridization (FISH) with an 18S rDNA probe. The diploid chromosome number in representatives of all four populations was invariably 2n = 42, with karyotypes composed of 12 pairs of metacentrics and 9 pairs of submetacentrics, without heteromorphic sex chromosomes. This kind of karyotype represents cytotype A in regard to cytotypes identified previously in H. malabaricus, exhibiting however, at the same time, some differences in the distribution of constitutive heterochromatin segments and in the locations... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chromosome banding; FISH; Cytotaxonomy of trahiras; Karyotype; NOR phenotype. |
Ano: 2005 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572005000100018 |
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Bellafronte,Elisangela; Schemberger,Michelle Orane; Artoni,Roberto Ferreira; Moreira Filho,Orlando; Vicari,Marcelo Ricardo. |
Parodontidae fish show few morphological characteristics for the identification of their representatives and chromosomal analyses have provided reliable features for determining the interrelationships in this family. In this study, the chromosomes of Apareiodon hasemani from the São Francisco River basin, Brazil, were analyzed and showed a karyotype with 2n = 54 meta/submetacentric chromosomes, and a ZZ/ZW sex chromosome system. The study revealed active NORs located on pair 11 and additional 18S rDNA sites on pairs 7 and 22. The 5S rDNA locus was found in pair 14. It showed a pericentric inversion regarding the ancestral condition. The satellite DNA pPh2004 was absent in the chromosomes of A. hasemani, a shared condition with most members of Apareiodon.... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cytogenetics; FISH; 18S rDNA; 5S rDNA; Neotropical fishes. |
Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572012000500010 |
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Vicari,Marcelo Ricardo; Noleto,Rafael Bueno; Artoni,Roberto Ferreira; Moreira-Filho,Orlando; Bertollo,Luiz Antonio Carlos. |
Karyotype data are presented for distinct species of the genus Astyanax from four rivers belonging to three different hydrographic basins of the State of Paraná, Brazil (Verde River - Tibagi basin, Açungui River - Ribeira basin, and Santo Antônio and Jaguariaíva Rivers - Jaguariaíva basin). Three karyotypic forms were identified, here denominated karyotype A (2n = 50 chromosomes, with 8m+18sm+10st+14a, and thirteen 18S rDNA sites); karyotype B (2n = 50 chromosomes, with 8m+18sm+10st+1f4a, and four 18S rDNA sites); and karyotype C (2n = 48 chromosomes, with 10m+16sm+10st+12a, and eight 18S rDNA sites). The pattern of constitutive heterochromatin was similar among the three karyotypic forms, with few differences. The 5S rDNA corresponds to a synapomorphic... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Karyotype evolution; Cytotaxonomy; RDNA sites; Biogeography. |
Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572008000200002 |
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Artoni,Roberto Ferreira; Shibatta,Oscar Akio; Gross,Maria Claudia; Schneider,Carlos Henrique; Almeida,Mara Cristina de; Vicari,Marcelo Ricardo; Bertollo,Luiz Antonio Carlos. |
Four populations of Astyanax aff. fasciatus of the upper rio Tibagi (municipal district of Ponta Grossa, Paraná State, Brazil), had their karyotypes and morphometry analyzed. The cytogenetic data show the occurrence of distinct karyotypes (cytotypes), here named cytotype A, with 2n=48 chromosomes (6m+18sm+14st+10a), cytotype B, with 2n=50 chromosomes (8m+18sm+14st+10a) and cytotype C, with 2n=50 chromosomes (8m+18sm+14st+10a). The distribution pattern of the constitutive heterochromatin was very similar between cytotypes A and B, but diverged in relation to cytotype C. Distinct cytotypes may occur in sympatry in the upper rio Tibagi region, with the exception of the Furna 2 sample, which presents cytotype A exclusively. In addition, a specimen with 2n=49... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Tetra; Morphometrics; Karyotype; Sympatry; Cryptic species. |
Ano: 2006 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252006000200005 |
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Moraes Neto,Américo; Silva,Maelin da; Matoso,Daniele Aparecida; Vicari,Marcelo Ricardo; Almeida,Mara Cristina de; Collares-Pereira,Maria João; Artoni,Roberto Ferreira. |
Karyotypic data are presented for four species of fish belonging to the Pimelodidae family. These species show a conserved diploid number, 2n = 56 chromosomes, with different karyotypic formulae. The analyzed species showed little amount of heterochromatin located preferentially in the centromeric and telomeric regions of some chromosomes. The nucleolus organizer regions activity (Ag-NORs) and the chromosomal location of ribosomal genes by fluorescent in situ hybridization (FISH), with 18S and 5S probes, showing only one chromosome pair marked bearer of ribosomal genes, the only exception was Pimelodus britskii that presented multiple NORs and syntenic location of the 18S and 5S probes. Non-Robertsonian events, as pericentric inversion and NORs duplication... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Pseudoplatystoma reticulatum; Pimelodus britskii; Sorubim lima; Steindachneridion parahybae. |
Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252011000100007 |
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Cipriano,Roger Raupp; Fenocchio,Alberto Sérgio; Artoni,Roberto Ferreira; Molina,Wagner; Noleto,Rafael Bueno; Kantek,Daniel Luis Zanella; Cestari,Marta Margarete. |
In this study, five species of marine fishes from the Paranaguá Bay in the Brazilian coast were evaluated. Eucinostomus argenteus and Diapterus rhombeus (Gerreidae) presented 48 chromosomes, all of which more acrocentric (FN = 48); Strongylura timucu and S. marina (Belonidae) also presented 48 chromosomes, but with a higher karyotypic complexity than the Gerreidae, 10M+2SM+36A (FN = 60) and 4M+44A (FN = 52), respectively. The fifth species, Mugil curema (Mugilidae), different than the others, presented only 28 chromosomes 20M+4ST+4A (FN = 48). The species presented diversity in the karyotypic macro-structure, which should be relevant for the cytotaxonomy and the evolution of this group of the vertebrate. |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Marine fishes; Karyotype; Cytotaxonomy; Karyotypic evolution. |
Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132008000200010 |
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Vicari,Marcelo Ricardo; Pazza,Rubens; Artoni,Roberto Ferreira; Margarido,Vladimir Pavan; Bertollo,Luiz Antonio Carlos. |
Hoplias malabaricus (trahyra) is a widespread fish species over the Neotropical region with diversified inter-populational karyotypes (cytotypes), which may correspond to a species complex. Despite the wide distribution in the South American basins, some authors have questioned its natural origin in the Iguaçu river, an important Brazilian river basin which is characterized by several endemic fish species. We have analyzed the karyotype of H. malabaricus from different collection sites of this river, by conventional and banding methods. Our results, in addition to our previous data concerning geographic distribution of the cytotypes, contribute to better understand the origin of H. malabaricus on the Iguaçu river, reinforcing the proposition that it is a... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chromosome evolution; Karyotypes distribution; Endemism. |
Ano: 2006 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132006000300015 |
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Registros recuperados: 16 | |
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