| Registro completo |
| Provedor de dados: |
Genet. Mol. Biol.
|
| País: |
Brazil
|
| Título: |
Identification and description of distinct B chromosomes in Cyphocharax modestus (Characiformes, Curimatidae)
|
| Autores: |
Santos,Lessandra Viviane De Rosa
Foresti,Fausto
Martins,Cesar
Oliveira,Claudio
Wasko,Adriane Pinto
|
| Data: |
2008-01-01
|
| Ano: |
2008
|
| Palavras-chave: |
B chromosomes
C-banding
Curimatidae
Cyphocharax modestus
Supernumerary chromosomes
|
| Resumo: |
Cytogenetic analyses were performed in Cyphocharax modestus, collected at Paranapanema River and Tietê River (São Paulo State, Brazil). A karyotype with 2n = 54 chromosomes was observed in the animals from both Brazilian freshwater river systems. One to four B chromosomes were also detected in individuals from the Paranapanema River, which represents the probable first report of more than a single supernumerary element in a species of the Curimatidae group. C-banding revealed centromeric and telomeric heterochromatin blocks in several chromosomes of the normal karyotype complement of C. modestus. Moreover, while some B chromosomes were characterized by the complete absence of C-bands, others were totally heterochromatic. Although there was a prevalence of B chromosomes in males of C. modestus, at least one supernumerary element was found in males and/or females of several other populations of the species, which suggests that the presence of these chromosomes seems to represent a general trait of C. modestus. A possible origin of the described B chromosomes may be related to the occurrence of a chromosome non-disjunction followed by the loss of euchromatic segments, an event that should have occurred in chromosomes that present conspicuous centromeric heterochromatic blocks and even in chromosomes that lack C-bands in this region, resulting in small supernumerary elements.
|
| Tipo: |
Info:eu-repo/semantics/article
|
| Idioma: |
Inglês
|
| Identificador: |
http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572008000200019
|
| Editor: |
Sociedade Brasileira de Genética
|
| Relação: |
10.1590/S1415-47572008000200019
|
| Formato: |
text/html
|
| Fonte: |
Genetics and Molecular Biology v.31 n.1 suppl.0 2008
|
| Direitos: |
info:eu-repo/semantics/openAccess
|
