Data/hora: 09/06/2024 04:46:34

Provedor de dados: | 74
País: | Brazil
Título: | Karyotype characterization and nucleolar organizer regions of marsupial species (Didelphidae) from areas of Cerrado and Atlantic Forest in Brazil
Autores: | Pereira,Núbia P.; Ventura,Karen; Silva Júnior,Magno C.; Silva,Daniela de Melo e; Yonenaga-Yassuda,Yatiyo; Pellegrino,Katia C. M.
Data: | 2008-12-01
Ano: | 2008
Palavras-chave: | Marsupials; Karyotypes; Cytogenetics; Didelphidae; NORs.
Resumo: | The karyotypes of 23 specimens belonging to 16 species from nine genera of Brazilian marsupials (family Didelphidae) were studied. The animals were collected in eight localities of Cerrado or Atlantic Forest biomes in the states of Goiás, Tocantins and São Paulo. The karyotypes were analyzed after conventional Giemsa staining and silver staining of the nucleolus organizer regions (Ag-NORs). New karyotypic data were obtained for  Gracilinanus microtarsus  (2n = 14, FN = 24), Marmosops paulensis  (2n = 14, FN = 24) , Micoreus paraguayanus  (2n = 14, FN = 20) and  Monodelphis rubida  (2n = 18, FN = 32) and are discussed in detail. The karyotypes of  G. microtarsus ,  M. paulensis  and  M. paraguayanus  include three large pairs of submetacentrics (pairs 1, 2 and 3) and a medium-sized metacentric or submetacentric pair 4. Pairs 5 and 6 are small submetacentrics in  G. microtarsus  and  M. paulensis  and acrocentrics in  M. paraguayanus .  M. paulensis  presented a single Ag-NOR in pair 6 (6p6p), while  M. paraguayanus  exhibited multiple Ag-NORs in pairs 5 and 6 (5pq5pq6p6p). There was variation in size and morphology of the sex chromosomes among these species.  Monodelphis rubida  presented a karyotype with 2n = 18 and FN = 32 composed of a large submetacentric pair 1, a medium-sized metacentric pair 2 and six pairs of submetacentrics (pairs 3 through 8). The X was a small acrocentric and the Y was dot-like. A single Ag-NOR bearing pair (5p5p) characterized  M. rubida.  Relevant karyotypic information was obtained for 19 specimens belonging to 12 species collected in areas sampled for the first time [ Caluromys lanatus  and  C. philander  (2n = 14, FN = 20),  Gracilinanus emiliae  (2n = 14, FN = 24),  Marmosa murina ,  Metachirus nudicaudatus  and  Micoureus demerarae  (2n = 14, FN = 20),  Monodelphis americana  (2n = 18, FN = 32) and  M. domestica  (2n = 18, FN = 20), and  Didelphis marsupialis, Philander frenata, P. opossum  and  P.  sp (2n = 22, FN = 20)]. Although the karyotypes were relatively conserved with respect to the morphology of the autosomes among species with the same diploid number, some differences regarding FN, sex chromosomes morphology and Ag-NORs patterns were detected.
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572008000500014
Editor: | Sociedade Brasileira de Genética
Relação: | 10.1590/S1415-47572008005000012
Formato: | text/html
Fonte: | Genetics and Molecular Biology  v.31 n.4 2008
Fonte: | info:eu-repo/semantics/openAccess