Voltar
Artigo Produção Nacional Revisado por pares
BIBTEX RIS

Nucleolar organizer regions in <i>Akodon arviculoides </i>(Cricetidae, Rodentia): evidence for the activity of rDNA genes in both X chromosomes of females

1983; Karger Publishers; Volume: 35; Issue: 2 Linguagem: Inglês

10.1159/000131857

ISSN

1424-8581

Autores

Yatiyo Yonenaga-Yassuda, M.F.L. de Assis, Sanae Kasahara, M. L’Abbate, Maria José de Souza,

Tópico(s)

Chromosomal and Genetic Variations

Resumo

Silver-stained cells from 13 specimens of <i>Akodon arviculoides </i>(2n = 14 and 15) were analyzed for the location and frequency of Ag-NOR’s. They were located terminally on four pairs of chromosomes, 3q, 4q, 5p, and Xp. In these 13 individuals, the number of Ag-NOR’s per cell varied between two and eight, and each chromosome had a characteristic pattern of frequency of NOR’s in each individual. Since in <i>A</i>. <i>arviculoides </i>a chromosomal polymorphism resulting from three autosomal pericentric inversions in chromosomes 2, 3, and 5 and a complex rearrangement involving chromosome 1 exist, it was possible to determine the frequency of Ag-staining in each homologue of these pairs in heterozygous individuals. Both X chromosomes had active NOR’s in the females. An Ag-NOR was also present on the single X chromosome of the males.

Referência(s)