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| Registros recuperados: 14 | |
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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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| Lorscheider,Carla Andreia; Oliveira,Jordana Inácio Nascimento; Dulz,Thais Aparecida; Nogaroto,Viviane; Martins-Santos,Isabel Cristina; Vicari,Marcelo Ricardo. |
| ABSTRACT The karyotypes of three armored catfish species (Loricariidae) from the Iguaçu river, southern of the Brazil, were compared using different techniques: C-banding, Ag-NOR and fluorescence in situ hybridization (FISH), which used 5S and 18S rDNAs and total Cot-1 fraction as probes. Hypostomus commersoni and Hypostomus derbyi presented 2n = 68 chromosomes, with karyotype formulae 12m+12sm+14st+30a and 12m+12sm+10st+34a, respectively; whereas Hypostomus myersi presented 2n = 74 chromosomes and 12m+16sm+12st+34a. The chromosomal localization of the Ag-NORs, 5S and 18S rDNAs differed in number of sites and chromosomal localization among the studied species. The total Cot-1 probe permitted the visualization of the repetitive DNA fraction in karyotypes of... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Armored catfish; FISH; Iguaçu river; Karyotype evolution. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132018000100435 |
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| Chirino,Mónica G.; Folgarait,Patricia J.; Gilbert,Lawrence E.; Lanzavecchia,Silvia; Papeschi,Alba G.. |
| Pseudacteon flies, parasitoids of worker ants, are being intensively studied as potentially effective agents in the biological control of the invasive pest fire ant genus Solenopsis (Hymenoptera: Formicidae). This is the first attempt to describe the karyotype of P. curvatus Borgmeier, P. nocens Borgmeier and P. tricuspis Borgmeier. The three species possess 2n = 6; chromosomes I and II were metacentric in the three species, but chromosome pair III was subtelocentric in P. curvatus and P. tricuspis, and telocentric in P. nocens. All three species possess a C positive band in chromosome II, lack C positive heterochromatin on chromosome I, and are mostly differentiated with respect to chromosome III. P. curvatus and P. tricuspis possess a C positive band,... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Pseudacteon; Karyotype evolution; C-banding; Fluorescent banding; FISH. |
| Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572009000400013 |
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| Domingues,Manoela de S.; Vicari,Marcelo R.; Abilhoa,Vinícius; Wamser,João P.; Cestari,Marta M.; Bertollo,Luiz A. C.; Almeida,Mara C. de; Artoni,Roberto F.. |
| The recently described fish species, Astyanax altiparanae (tetra) is common in the upper rio Paraná basin, and has been reported in the Iguaçu basin. However, its natural origin in the rio Iguaçu is questionable. In the present work, karyotypical and morphological features of two populations of Astyanax altiparanae from the upper rio Tibagi and upper rio Iguaçu were compared. Both populations showed 2n=50 chromosomes and differences in their karyotype formula, NOR-bearing chromosomes and location of heterochromatin. Morphometric data from both populations were analyzed through free-size canonical variables. Cytogenetic and morphological results were mostly coincident showing exclusive markers that reflect their degree of populational isolation. In addition... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Tetra; Karyotype evolution; Distribution; Morphometry. |
| Ano: 2007 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252007000100005 |
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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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| Pucci,Marcela Baer; Nogaroto,Viviane; Moreira-Filho,Orlando; Vicari,Marcelo Ricardo. |
| Abstract Eukaryotic genomes consist of several repetitive DNAs, including dispersed DNA sequences that move between chromosome sites, tandem repeats of DNA sequences, and multigene families. In this study, repeated sequences isolated from the genome of Characidium gomesi were analyzed and mapped to chromosomes in Characidium zebra and specimens from two populations of C. gomesi. The sequences were transposable elements (TEs) named retroelement of Xiphophorus (Rex); multigene families of U2 small nuclear RNA (U2 snRNA); and histones H1, H3, and H4. Sequence analyses revealed that U2 snRNA contains a major portion corresponding to the Tx1-type non-LTR retrotransposon Keno, the preferential insertion sites of which are U2 snRNA sequences. All histone... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Mobile DNA; Histones; Karyotype evolution; SnRNA; WZ/ZZ. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572018000400585 |
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| Scher,Ricardo; Pompolo,Silvia das Graças. |
| Cytogenetic analysis based on the distribution of C-bands showed two groups of karyotypes in a Trypoxylon nitidum population from the Rio Doce Park, State of Minas Gerais, Brazil. One of these groups, that was identical to a previously described karyotype (n = 15; 2n = 30), had a stable chromosome number and was rich in acrocentric chromosomes, whereas the other had a variable chromosome number (n = 12 to 14; 2n = 25 to 28) and was rich in pseudo-acrocentric chromosomes. We propose a hypothesis explaining the dynamics of the modifications which occurred in the karyotype of this species, based on the minimum interaction theory of Imai et al. (1986, 1988, 1994) and on the chromosome rearrangements and heteromorphisms observed by us. |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: C-banding; Trypoxylon nitidum; Karyotype evolution. |
| Ano: 2003 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572003000300015 |
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| Fernandes,Carlos Alexandre; Aguiar,Allan Kardec Moreira de; Paiz,Leonardo Marcel; Baumgärtner,Lucas; Piscor,Diovani; Margarido,Vladimir Pavan. |
| ABSTRACT Gymnorhamphichthys britskii is a Neotropical electric fish of family Rhamphichthyidae described from the Paraná-Paraguay system. This study reports the first karyotypic description of G. britskii collected from the upper Paraná river basin, which presented 2n=38 chromosomes, karyotype composed of 14 metacentric, 8 submetacentric, 2 subtelocentric and 14 acrocentric chromosomes, and fundamental number as 62 for both sexes. Heteromorphic sex chromosomes were absent. A single pair of nucleolar organizing regions (NORs) was detected in the submetacentric chromosome pair number 9 by silver staining and confirmed by the 18S rDNA probe. The 5S rDNA was located in a single chromosome pair. Heterochromatic regions were clearly observed in the short arms of... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Ag-NORs; C-banding; Fish cytogenetics; Karyotype evolution; Repetitive sequences. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252019000300205 |
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| Fregonezi,Jéferson Nunes; Fernandes,Thiago; Torezan,José Marcelo Domingues; Vieira,Ana Odete S.; Vanzela,André Luís Laforga. |
| We studied the karyotypes of four Brazilian Cestrum species (C. amictum, C. intermedium, C. sendtnerianum and C. strigilatum) using conventional Feulgen staining, C-Giemsa and C-CMA3/DAPI banding, induction of cold-sensitive regions (CSRs) and fluorescent in situ hybridization (FISH) with rDNA probes. We found that the karyotypes of all four species was 2n = 2x = 16, with, except for the eighth acrocentric pair, a predominance of meta- and submetacentric chromosomes and various heterochromatin classes. Heterochromatic types previously unreported in Cestrum as neutral C-CMA3(0)/DAPI0 bands, CMA3+ bands not associated with NORs, and C-Giemsa/CSR/DAPI- bands were found. The heterochromatic blocks varied in size, number, position and composition. The 45S rDNA... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cestrum; Chromosome banding; CSRs; Karyotype evolution; RDNA probes. |
| Ano: 2006 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572006000100019 |
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| Utsunomia,Ricardo; Pansonato-Alves,José C.; Costa-Silva,Guilherme J.; Mendonça,Fernando F.; Scacchetti,Priscilla C.; Oliveira,Claudio; Foresti,Fausto. |
| The fish species Synbranchus marmoratushas been reported to exist as a species complex due to high intraspecific karyotypic variability in spite of the difficulty or impossibility to distinguish them using morphological traits alone. The goal of this work was to use cytogenetic and molecular methods to determine the species delimitations and understand the karyoevolution ofS. marmoratususing samples collected from distinct Brazilian localities. Among the analyzed specimens, a large degree of cytogenetic variation related to diploid numbers and karyotype structure was observed, with karyotypes showing 2n=42, 44 and 46 chromosomes. In addition, using sequences of three mitochondrial genes, the phylogenetic relationships between every sample with a known... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chromosomal diversity; Fish cytogenetics; Karyotype evolution; Repetitive DNA; Species complex. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252014000400903 |
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| Scali, V.; Milani, L.; Passamonti, M.. |
| Leptynia specimens were analyzed by karyotype analysis, mitochondrial gene sequencing and SEM of bodies and eggs. Here we describe a new species, Leptynia annaepaulae, and three subspecies of L. attenuata Pantel (L. attenuata attenuata, L. attenuata iberica, L. attenuata algarvica). The phylogeny of the genus Leptynia is congruent with a karyotype trend toward a reduction of chromosome number and the shift from the shared XX/X0 sex chromosome formula to the unusual XX/XY one. Chromosome repatterning appears to occur ahead of genetic differentiation, following a chromosome model of cladogenesis. Chromosome and genetic differentiation, in turn, appears to precede morphological distinction, thus realizing a condition of incipient species for most of the... |
| Tipo: Article / Letter to the editor |
Palavras-chave: Chromosome speciation; Karyotype evolution; Leptynia annaepaulae spn.; Leptynia attenuata sspn.; SEM morphology; 42.75. |
| Ano: 2012 |
URL: http://www.repository.naturalis.nl/record/447986 |
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| Registros recuperados: 14 | |
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