Consulta: subjectFacets:"Diploid number"
Registros recuperados: 4
Data/hora: 11/06/2024 07:56:46

Chromosome evolution in fishes: a new challenging proposal from Neotropical species
Provedor de dados: 83
Autores: Nirchio,Mauro; Rossi,Anna Rita; Foresti,Fausto; Oliveira,Claudio.
We present a database containing cytogenetic data of Neotropical actinopterygian fishes from Venezuela obtained in a single laboratory for the first time. The results of this study include 103 species belonging to 74 genera assigned to 45 families and 17 out of the 40 teleost orders. In the group of marine fishes, the modal diploid number was 2n=48 represented in 60% of the studied species, while in the freshwater fish group the modal diploid complement was 2n=54, represented in 21.21 % of the studied species. The average number of chromosomes and the mean FN were statistically higher in freshwater fish than in marine fish. The degree of diversification and karyotype variation was also higher in freshwater fish in contrast to a more conserved cytogenetic...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Actinopterygii; Ancestral karyotype; Diploid number; Fundamental number.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252014000400761

Diversity and chromosomal evolution in the genusAncistrusKner, 1854 (Loricariidae: Ancistrini) from three hydrographic basins of Mato Grosso State, Brazil
Provedor de dados: 83
Autores: Mariotto,Sandra; Centofante,Liano; Moreira-Filho,Orlando.
Cytogenetic analyses were carried out in 117 specimens of seven species of the genus Ancistrus from three hydrographic in Mato Grosso State: Paraguay, Araguaia-Tocantins and Amazon basins. Conventional cytogenetic techniques were used to obtain mitotic chromosomes. C-banding was performed to detect heterochromatic regions and silver nitrate staining was used to identify nucleolar organizer regions (Ag-NORs). The counted and paired chromosomes revealed diploid numbers ranging from 2n = 40 to 2n = 54 with karyotype formulae varying from FN = 80 to FN = 86. Single marks in distinct chromosomes identified the nucleolar organizer regions. The constitutive heterochromatin was scarce in the diploid number from 2n = 50 to 2n = 54 and conspicuous blocks were...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: AgNOR; Cytogenetic; Diploid number; Heterochromatin.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252013000100125

Conserved number of U2 snDNA sites in Piabina argentea, Piabarchus stramineus and two Bryconamericus species (Characidae, Stevardiinae)
Provedor de dados: 83
Autores: Piscor,Diovani; Fernandes,Carlos Alexandre; Parise-Maltempi,Patricia P.
ABSTRACT The chromosomal location of 5S rRNA and U2 snRNA genes of Piabina argentea, Piabarchus stramineus and two Bryconamericus species from two different Brazilian river basins were investigated, in order to contribute to the understanding of evolutionary characteristics of these repetitive DNAs in the subfamily Stevardiinae. The diploid chromosome number was 2n = 52 for Bryconamericus cf. iheringii, Bryconamericus turiuba, Piabarchus stramineus and Piabina argentea. The 5S rDNA clusters were located on one chromosome pair in P. stramineus and B. cf. iheringii, and on two pairs in B. turiuba and P. argentea. The U2 snDNA clusters were located on the one pair in all species. Two-color FISH experiments showed that the co-localization between 5S rDNA and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Repetitive DNA; Splicing; 5S rDNA; Chromosome; Diploid number.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252018000100207

Updating the list of chromosome numbers for Philodendron (Araceae)
Provedor de dados: 39
Autores: Vasconcelos,Emanuelle V.; Brasileiro-Vidal,Ana C.; Benko-Iseppon,Ana M.; Vasconcelos,Santelmo.
ABSTRACT Aiming for a better understanding of karyotype evolution within Philodendron, we report chromosome counts for 23 species of the genus, of which 19 are being reported for the first time, thus increasing to 84 ( ca. 17 % of the genus) the total number of species with available chromosome counts. The diploid numbers 2 n = 32 and 2 n = 34 were the most common, with 10 and 11 species, respectively, whereas only two species presented different chromosome numbers ( P. giganteum with 2 n = 30 and P. adamantinum with 2 n = 36). The results are discussed in the context of previous analyses of karyotypes of Philodendron spp., taking into account bidirectional dysploidy as the main mechanism of chromosome number evolution within the genus.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Aroids; Diploid number; Dysploidy; Karyotype; Philodendron.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062017000200309