Data/hora: 02/06/2024 04:53:03

Provedor de dados: | 74
País: | Brazil
Título: | Heterochromatin diversity and its co-localization with 5S and 45S rDNA sites in chromosomes of four Maxillaria species (Orchidaceae)
Autores: | Cabral,Juliano S.; Felix,Leonardo P.; Guerra,Marcelo.
Data: | 2006-01-01
Ano: | 2006
Palavras-chave: | Heterochromatin; CMA and DAPI; 45S and 5S rDNA; Maxillaria.
Resumo: | We investigated four orchids of the genus Maxillaria (M. discolor, M. acicularis, M. notylioglossa and M. desvauxiana) in regard to the position of heterochromatin blocks as revealed using chromomycin A3 (CMA) and 4'-6-diamidino-2-phenylindole (DAPI) fluorochrome staining and 5S and 45S rDNA sites using fluorescence in situ hybridization (FISH). The species showed differences in chromosome number and a diversified pattern of CMA+ and DAPI+ bands, including heteromorphism for CMA+ bands. The 5S and 45S rDNA sites also varied in number and most of them were co-localized with CMA+ bands. The relationship between 5S rDNA sites and CMA+ bands was more evident in M. notylioglossa, in which the brighter CMA+ bands were associated with large 5S rDNA sites. However, not all 5S and 45S rDNA sites were co-localized with CMA+ bands, probably due to technical constraints. We compare these results to banding data from other species and suggest that not all blocks of tandemly repetitive sequences, such as 5S rDNA sites, can be observed as heterochromatin blocks.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572006000400015
Editor: | Sociedade Brasileira de Genética
Relação: | 10.1590/S1415-47572006000400015
Formato: | text/html
Fonte: | Genetics and Molecular Biology  v.29 n.4 2006
Fonte: | info:eu-repo/semantics/openAccess