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Konerat,Jocicléia Thums; Bueno,Vanessa; Baumgartner,Lucas; Martins-Santos,Isabel Cristina; Margarido,Vladimir Pavan. |
B chromosomes are extra chromosomes from the normal chromosomal set, found in different organisms, highlighting their presence on the group of fishes. Callichthys callichthys from the upper Paraná River has a diploid number of 56 chromosomes (26 m-sm + 30 st-a) for both sexes, with the presence of a sporadically acrocentric B chromosome. Moreover, one individual presented a diploid number of 57 chromosomes, with the presence of a morphologically ill-defined acrocentric B chromosome in all analyzed cells. The physical mapping of 5S and 18S rDNA shows multiple 5S rDNA sites and only one pair of chromosomes with 18S sites in C. callichthys, except for two individuals. These two individuals presented a third chromosome bearing NORs (Ag-staining and 18S rDNA)... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: 18S rDNA; 5S rDNA; Chromosomal rearrangements; FISH; Supernumerary chromosome. |
Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252014000300603 |
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Valentim,Francisco Carlos de Souza; Porto,Jorge Ivan Rebelo; Feldberg,Eliana. |
Abstract Cytogenetic studies in the subfamily Potamotrygoninae have provided valuable insights into the understanding of the evolution and diversification of its species. In the present study, the chromosomal features of seven nominal potamotrygonin species are provided: Plesiotrygon iwamae (2n=74, FN=120), Potamotrygon amazona (2n=66, FN=107), P. constellata (2n=66, FN=110), P. leopoldi (2n=64, FN=102), P. motoro (2n=66, FN=106) from four different localities, and P. orbignyi (2n=66, FN=106), P. scobina (2n=66, FN=104), from Central Amazon. Additionally, we found a new karyomorph in P. wallacei. We considered the localization of Nucleolus Organizer Regions (NORs), as well as the pattern of constitutive heterochromatin, as species-specific characters. We... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Elasmobranchs; Cytogenetics; Chromosomal rearrangements; Sex chromosomes; Karyotypic diversity. |
Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572019000400578 |
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Silva,Fernando Henrique Ramos; Pieczarka,Julio Cesar; Cardoso,Adauto Lima; Silva,Patrícia Corrêa da; Oliveira,Jonas Alves de; Nagamachi,Cleusa Yoshiko. |
Cytogenetic studies were carried out on samples of Parapteronotus hasemani, Sternarchogiton preto and Sternarchorhamphus muelleri (Apteronotidae, Gymnotiformes) from the Amazon basin. The first two species exhibited both a 2n = 52 karyotype, but differed in their karyotypic formulae, distribution of constitutive heterochromatin, and chromosomal location of the NOR. The third species, Sternarchorhamphus muelleri, was found to have a 2n = 32 karyotype. In all three species the DAPI and chromomycin A3 staining results were consistent with the C-banding results and nucleolar organizer region (NOR) localization. The 18S rDNA probe confirmed that there was only one pair of ribosomal DNA cistron bearers per species. The telomeric probe did not reveal interstitial... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Fluorochromes; FISH; Chromosomal rearrangements; Biodiversity. |
Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572014000500006 |
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Bülau,Sandra Eloisa; Kretschmer,Rafael; Gunski,Ricardo José; Garnero,Analía del Valle; O’Brien,Patricia C. M.; Ferguson-Smith,Malcolm A.; Oliveira,Edivaldo Herculano Correa de; Freitas,Thales Renato Ochotorena de. |
Abstract Zonotrichia capensis is widely distributed in the Neotropics. Previous cytogenetic studies demonstrated the presence of polymorphisms in two chromosome pairs (ZCA2 and ZCA4). Here, we report results based on comparative chromosome painting, using probes derived from Gallus gallus and Leucopternis albicollis, focused on characterizing the chromosome organization of Z. capensis. Our results demonstrate the conservation of ancestral syntenies as observed previously in other species of passerine. Syntenies were rearranged by a series of inversions in the second chromosome as described in other Passeriformes, but in this species, by using probes derived from L. albicollis we observed an extra inversion in the second chromosome that had not previously... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Birds; Chromosomal rearrangements; Molecular cytogenetics; FISH. |
Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572018000500799 |
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Garcia,Caroline; Moreira Filho,Orlando. |
Karyotypes and other chromosomal markers were investigated in three species of the catfish genus Pimelodus, namely P. fur, P. maculatus and Pimelodus sp., from municipality of Três Marias, Minas Gerais, Brazil, using differential staining techniques (C-banding, Silver nitrate and CMA3 staining). The diploid chromosome number was 2n = 56 in P. maculatus and Pimelodus sp., while in P. fur 2n = 54. The karyotype of P. fur consisted in 32M + 8SM + 6ST + 8A with fundamental number (NF) of 100, that of P. maculatus 32M + 12SM + 12A with NF = 112, and that of Pimelodus sp. had 32M + 12Sm + 6ST + 6A with NF = 106.The nucleolar organizer regions (NORs) in all three species were invariably detected in telomeres of longer arm of the 20th chromosome pair. These sites... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Fish cytogenetics; Diploid number reduction; Chromosomal rearrangements; Chromosome banding; Catfishes. |
Ano: 2005 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252005000200006 |
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Auvinet, Juliette; Graça, Paula; Dettai, Agnès; Amores, Angel; Postlethwait, John H.; Detrich, H. William; Ozouf-costaz, Catherine; Coriton, Olivier; Higuet, Dominique. |
Background Chromosomal rearrangements are thought to be an important driving force underlying lineage diversification, but their link to speciation continues to be debated. Antarctic teleost fish of the family Nototheniidae (Notothenioidei) diversified in a changing environmental context, which led to ecological, morphological, and genetic differentiation among populations. In addition, extensive chromosomal repatterning accompanied species divergence in several clades. The most striking karyotypic changes involved the recent species radiation (about 10 My) of the genus Trematomus, with chromosomal pair numbers ranging between 29 and 12. These dramatic reductions in chromosome number resulted mostly from large-scale chromosome fusions. Multiple centric... |
Tipo: Text |
Palavras-chave: BAC-FISH; Chromosomal painting; Chromosomal rearrangements; Chromosomal structural units; Chromosomal synteny; Nototheniidae; Speciation. |
Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00615/72731/71831.pdf |
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Kretschmer,Rafael; de Oliveira,Thays Duarte; de Oliveira Furo,Ivanete; Oliveira Silva,Fabio Augusto; Gunski,Ricardo José; del Valle Garnero,Analía; de Bello Cioffi,Marcelo; de Oliveira,Edivaldo Herculano Corrêa; de Freitas,Thales Renato Ochotorena. |
Abstract An extensive karyotype variation is found among species belonging to the Columbidae family of birds (Columbiformes), both in diploid number and chromosomal morphology. Although clusters of repetitive DNA sequences play an important role in chromosomal instability, and therefore in chromosomal rearrangements, little is known about their distribution and amount in avian genomes. The aim of this study was to analyze the distribution of 11 distinct microsatellite sequences, as well as clusters of 18S rDNA, in nine different Columbidae species, correlating their distribution with the occurrence of chromosomal rearrangements. We found 2n values ranging from 76 to 86 and nine out of 11 microsatellite sequences showed distinct hybridization signals among... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Birds; FISH; Microsatellites; Sex chromosomes; Chromosomal rearrangements. |
Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572018000100098 |
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