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Nucleolar organizer regions, G-and C-bands in some Brazilian species of didelphidae

Maria José de Souza; Vilna Maia; José Ferreira dos Santos

Departamento de Biologia Geral, Centro de Ciências Biológicas, Universidade Federal de Pernambuco, Cidade Universitária, 50000 Recife, PE, Brasil

ABSTRACT

Karyotypes of four didelphid marsupial species (Marmosa murina, M. cinerea, Caluromys philander and C. lanatus) showed a similar complement of 2n = 14, NF = 20. The results demonstrate an extensive homeology of the G-banding patterns but there are considerable differences in the constitutive heterochromatic patterns and nucleolar organizer regions (NORs), as shown by C-banding and silver staining techniques.

Keywords: Nucleolar organizer regions; G-and; C-bands; Didelphidae.

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