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| Prestes,Anahiê Bortoncello; Nardelli,Aline; Paiz,Leonardo Marcel; Gavazzoni,Mariane; Margarido,Vladimir Pavan. |
| ABSTRACT Bryconamericus is a highly diverse group of characid fishes, being cytogenetic a valuable tool for the delimitation of species. Bryconamericus aff. iheringii (Upper Uruguay/Lower Paraná), B. coeruleus (Upper Paraná), B. cf. ecai e B. cf. eigenmanni (Upper Uruguay) were studied cytogenetically, and presented 2n=52 chromosomes, with interpopulational/interspecific variation of karyotype and fundamental number. Heterochromatin was evidenced in pericentromeric, telomeric and interstitial regions, and it was shown to be an important cytogenetic marker. Single nucleolar organizing regions (NORs) were found in B. cf. eigenmanni, B. cf. ecai and B. aff. iheringii (Lower Paraná), and multiple in B. aff. iheringii (Upper Uruguay) and B. coeruleus, with... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chromosome rearrangements; Co-localization; Cytotaxonomy; Cytosystematics; Intra and interspecific variation; Ribosomal genes. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252019000300203 |
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| Nirchio,Mauro; Rondón,Rodolfo; Oliveira,Claudio; Ferreira,Irani A.; Martins,Cesar; Pérez,Julio; Sola,Luciana; Rossi,Anna Rita. |
| In the present study, three species of Lutjaninae, Lutjanus analis, L. griseus and L. synagris, were analyzed by conventional Giemsa staining, C-banding and silver staining, to reveal active Nucleolus Organizer Regions (NORs). Fluorescent in situ hybridization (FISH) was also applied to establish the number and location of the ribosomal gene clusters (18S and 5S rRNA genes). Counts of diploid metaphasic cells revealed a diploid modal chromosome complement composed of 48 acrocentric chromosomes in both L. analis and L. griseus. Two cytotypes were observed in L. synagris: cytotype I, with 2n=48 acrocentric chromosomes, found in 19 specimens, and cytotype II, with 46 acrocentric chromosomes and one large metacentric, found in two specimens. The large... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Karyotype; Ribosomal genes; NOR polymorphism; C-banding; Robertsonian rearrangement. |
| Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252008000100012 |
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| Ghigliotti,Laura; Mazzei,Federico; Ozouf-Costaz,Catherine; Christiansen,Jørgen S.; Fevolden,Svein-Erik; Pisano,Eva. |
| The capelin, Mallotus villosus (Osmeriformes, Osmeridae), is an ecological and commercial key component of the sub-arctic ichthyofauna. Here, we provide the first cytogenetic information on the species based on both conventional karyotyping and chromosomal mapping of 45S and 5S ribosomal genes through fluorescence in situ hybridization (FISH). The capelin genome displayed a diploid number of 54 with the karyotypic formula 26m/sm+28st/a and a fundamental number (FN) = 80. Both classes of ribosomal genes appeared to be spread out to multiple chromosomal locations, i.e. the 45S and 5S rDNA clusters were detected on six and seven chromosome pairs, respectively. A linked chromosomal organization of the major and minor ribosomal genes classes has been visualized... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Capelin; Chromosomes; Osmeridae; Ribosomal genes. |
| Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572008000200003 |
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| Nakayama,Celeste Mutuko; Feldberg,Eliana; Bertollo,Luiz Antonio Carlos. |
| Six species of Serrasalmidae from the central Amazon, representatives of the genera Serrasalmus (S. elongatus, S. maculatus, S. cf. rhombeus, and S. rhombeus), Pygocentrus (P. nattereri), and Colossoma (C. macropomum), were analyzed regarding the distribution of the Ag-NORs, C-positive heterochromatin and 18S and 5S rRNA genes on the chromosomes. All specimens had 2n = 60 chromosomes, except S. cf. rhombeus, with 2n = 58, and C. macropomum with 2n = 54 chromosomes. The Ag-NORs were multiple and located on the short arms of subtelo-acrocentric chromosomes in all Serrasalmus species and in P. nattereri, but were found on metacentric chromosomes in C. macropomum. The 18S rDNA sites were usually coincident with Ag-NORs, although some species had a higher... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chromosomal evolution; Fish; Heterochromatin; Piranhas; Ribosomal genes. |
| Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252012000100005 |
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