Data/hora: 06/06/2024 01:16:38

Provedor de dados: 	Neotropical Ichthyology	
País: 	Brazil	
Título: 	Cytogenetic study of two species of the family Pimelodidae (Siluriformes) collected in lago Guaíba, Rio Grande do Sul, Brazil	
Autores: 	Treco,Fernando Rodrigo; Malabarba,Luiz R.; Giuliano-Caetano,Lucia; Dias,Ana Lúcia.	
Data: 	2008-03-01	
Ano: 	2008	
Palavras-chave: 	Parapimelodus; Pimelodus; NOR; Heterochromatin; Fluorochromes.	
Resumo: 	A cytogenetic study was conducted on specimens of Parapimelodus nigribarbis and Pimelodus maculatus collected in the lago Guaíba drainage, Porto Alegre, Rio Grande do Sul, Brazil. The two species had a diploid number of 56 chromosomes, with P. nigribarbis showing a karyotype of 20m + 20sm + 4st + 12a with FN of 100, and P. maculatus showing a karyotype of 24m + 20sm + 6st + 6a with FN of 106. NORs were demonstrated in both species in only one pair of subtelocentric chromosomes, in the terminal region of the long arm, which was coincident with C- banding and CMA3 staining, while DAPI staining was negative in these regions. Parapimelodus nigribarbis had a greater number of heterochromatic bands than did P. maculatus, which were distributed mainly in the terminal regions, where the latter species showed an interstitial band on the short arm of the first metacentric pair. C-banding plus CMA3 demonstrated heterochromatin that was associated with GC-rich NORs in both P. nigribarbis and P. maculatus, although other fluorescent regions were also observed in the former species. With C-banding plus DAPI, various chromosomal regions were stained in the two species, along with interstitial staining in P. maculatus, indicating that heterochromatin contained a greater quantity of AT-rich regions.	
Tipo: 	Info:eu-repo/semantics/article	
Idioma: 	Inglês	
Identificador: 	http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252008000100010	
Editor: 	Sociedade Brasileira de Ictiologia	
Relação: 	10.1590/S1679-62252008000100010	
Formato: 	text/html	
Fonte: 	Neotropical Ichthyology  v.6 n.1 2008	
Fonte: 	info:eu-repo/semantics/openAccess