Teses em Neurociências e Biologia Celular (Doutorado) - PPGNBC/ICB
URI Permanente para esta coleçãohttps://repositorio.ufpa.br/handle/2011/2390
O Doutorado Acadêmico pertence ao Programa de Pós-Graduação em Neurociências e Biologia Celular (PPGNBC) do Instituto de Ciências Biológicas (ICB) da Universidade Federal do Pará (UFPA).
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Navegando Teses em Neurociências e Biologia Celular (Doutorado) - PPGNBC/ICB por Assunto "Accipitridae"
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Item Acesso aberto (Open Access) Aplicação de pintura cromossômica em espécies da família Accipitridae (Aves, Falconiformes): considerações filogenéticas e evolutivas(Universidade Federal do Pará, 2013-10-18) TAGLIARINI, Marcella Mergulhão; OLIVEIRA, Edivaldo Herculano Correa de; http://lattes.cnpq.br/0094007714707651Cytogenetic analyses of Falconiformes have showed that Accipitridae have atypical chromosomal organization among birds, with relatively low diploid numbers (mean of 2n=66) and a few pairs of microchromosomes (4 to 6 pairs). Proposals based on classical cytogenetics suggested that this fact was a result of fusions of microchromosomes found in the Avian putative ancestor karyotype. With the aim of contributing to clarify questions concerning chromosomal evolution and phylogenetics of this family, we analyzed three species of subfamily Buteoninae (Rupornis magnirostris, Buteogallus meridionales e Asturina nítida) and two of subfamily Harpiinae (Harpia harpyja e Morphnus guianensis) by means of classical and molecular cytogenetics. Buteoninae species showed karyotypes with diploid number 68 and FN varying from 100 to 102; the number of biarmed chromosomes varied between 17 and 21, Z chromosome was submetacentric and W chromosome was metacentric in R. magnirostris and submetacentric in Asturina nitida. 18/28 rDNA probes showed that nucleolar organizer regions are located in a medium-sized submetacentric pair, corresponding to the short arm of pair 7. Telomeric sequences were found not only on terminal region of the chromosomes, but also on some interstitial regions. Whole-chromosome paints derived from pairs 1 to 11 of Gallus gallus (GGA) produced the same number of signals in these species. The availability of whole-chromosome probes derived of Leucopternis albicollis confirmed the presence of a common cytogenetic signature for Buteoninae species, corresponding to the association between GGA1p and GGA6. An interstitital telomeric sequence found in this pair reinforces this fact. Concerning the species of Harpiinae, the conventional staining analyses showed that H. harpyja and M. guianensis have 2n=58 and 2n=56, respectively. Both species have 22 pairs of biarmed chromosomes, although H. harpyja has two more chromosomes than M. guianensis. 18/28S rDNA mapped on the short arm of pair 1 in M. guianensis and in two pairs in H, harpyja (6 and 25). Telomeric sequences were found on the terminal regions, but also on interstitial locations in some chromosomes. Despite the apparent karyotypic similarity, no common associations were found in these two species. The different associations observed in Morphnus and Harpia indicate that these species suffered an extensive genomic reorganization after their separation in two independent lineages. Moreover, the absence of shared associations suggests that the fissions of macrochromosomes have occurred in the common ancestor of this group, and that fusions were subsequent to their isolation as different lineages. Our results, together with previous reports in other species of Accipitridae, indicate that the processes of fissions involving the macrochromosomes of GGA and fusions between these segments and between them and microchromosomes are recurrent rearrangements in this group. Although Falconidae species also show atypical karyotypes, with low diploid numbers, global cytogenetic data of Accipitridae indicate that, similarly to the morphological traits between these two families, the rearranged karyotypes would correspond to homoplasies, from the evolutionary point of view, supporting the idea that these families do not form a monophyletic group.