Constitutive Heterochromatin
Mostrando 13-24 de 97 artigos, teses e dissertações.
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13. Comparative cytogenetic analysis of two grasshopper species of the tribe Abracrini (Ommatolampinae, Acrididae)
The grasshopper species Orthoscapheus rufipes and Eujivarus fusiformis were analyzed using several cytogenetic techniques. The karyotype of O. rufipes, described here for the first time, had a diploid number of 2n = 23, whereas E. fusiformis had a karyotype with 2n = 21. The two species showed the same mechanism of sex determination (XO type) but differed in
Genetics and Molecular Biology. Publicado em: 2011
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14. The karyotype of Adenomera diptyx (Boettger 1885) (Anura, Leptodactylidae) from northeastern Argentina
In this work we analyzed the karyotype of five populations of Adenomera diptyx from Argentina after conventional staining, Ag-NOR and C-banding. All specimens presented 2n = 26 and FN = 34. The karyotype was formed by three submetacentric, one metacentric and nine telocentric pairs. Silver staining revealed that the NOR was located on a secondary constrictio
Genetics and Molecular Biology. Publicado em: 22/12/2010
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15. Cytogenetic analysis of Astylus antis (Perty, 1830) (Coleoptera, Melyridae): Karyotype, heterochromatin and location of ribosomal genes
Cytogenetic analysis of Astylus antis using mitotic and meiotic cells was performed to characterize the haploid and diploid numbers, sex determination system, chromosome morphology, constitutive heterochromatin distribution pattern and chromosomes carrying nucleolus organizer regions (NORs). Analysis of spermatogonial metaphase cells revealed the diploid num
Genetics and Molecular Biology. Publicado em: 07/06/2010
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16. Mitotic and meiotic chromosomes of a southern brazilian population of Boophilus microplus (Acari, Ixodidae)
Using conventional staining with acetic orcein and C-banding techniques it was investigated constitutive heterochromatin chromosomal polymorphisms and the mitotic and the meiotic behavior of male and female chromosomes of Boophilus microplus (Canestrini, 1887). Some differences were detected in the population of southern Brazil as compared to the data of oth
Publicado em: 2010
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17. Comparative cytogenetic analysis between Lonchorhina aurita and Trachops cirrhosus (Chiroptera, Phyllostomidae)
Phyllostomidae comprises the most diverse family of neotropical bats, its wide range of morphological features leading to uncertainty regarding phylogenetic relationships. Seeing that cytogenetics is one of the fields capable of providing support for currently adopted classifications through the use of several markers, a comparative analysis between two Phyl
Genetics and Molecular Biology. Publicado em: 06/11/2009
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18. Comparative cytogenetics of three species of Dichotomius (Coleoptera, Scarabaeidae)
Meiotic and mitotic chromosomes of Dichotomius nisus, D. semisquamosus and D. sericeus were analyzed after conventional staining, C-banding and silver nitrate staining. In addition, Dichotomius nisus and D. semisquamosus chromosomes were also analyzed after fluorescent in situ hybridization (FISH) with an rDNA probe. The species analyzed had an asymmetrical
Genetics and Molecular Biology. Publicado em: 01/05/2009
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19. Hidden heterochromatin: characterization in the Rodentia species Cricetus cricetus, Peromyscus eremicus (Cricetidae) and Praomys tullbergi (Muridae)
The use of in situ restriction endonuclease (RE) (which cleaves DNA at specific sequences) digestion has proven to be a useful technique in improving the dissection of constitutive heterochromatin (CH), and in the understanding of the CH evolution in different genomes. In the present work we describe in detail the CH of the three Rodentia species, Cricetus c
Genetics and Molecular Biology. Publicado em: 2009
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20. CaracterizaÃÃo citogenÃtica de Leptoglossus gonagra e Pachylis aff pharaonis (Heteroptera, Coreidae)
AnÃlise cromossÃmica de Leptoglossus gonagra (2n=21=18A+2m+X0) e Pachylis aff pharaonis (2n=15=12A+2m+X0) revelou cromossomos holocÃntricos que decrescem gradualmente de tamanho. Nas duas espÃcies, o cromossomo X mostrou tamanho mÃdio e os cromossomos m correspondem aos menores elementos do cariÃtipo. As duas espÃcies mostraram a heterocromatina const
Publicado em: 2009
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21. AnÃlise cariotÃpica, heterocromatina constitutiva e frequÃncia de expressÃo das RONs em duas espÃcies de Melanoplinae (Orthoptera: Acrididae)
A subfamÃlia Melanoplinae constitui um grupo de gafanhotos com a maior diversidade cariotÃpica dentro de Acrididae. O objetivo principal deste trabalho foi estudar cromossomos meiÃticos dos melanoplÃneos Baeacris punctulatus e Dichroplus fuscus atravÃs de diferentes tÃcnicas citogenÃticas. Baeacris punctulatus e D. fuscus apresentaram os cariÃtipos 2
Publicado em: 2009
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22. Mapping of ribosomal genes and chromosomal markers in three species of the genus Serrasalmus (Characidae, Serrasalminae) from the Amazon basin
Karyotypic characteristics of three species of the genus serrasalmus ( S. altispinnis , S. gouldingi and S. Serrulatus ) from the middle and lower Negro River, Amazon Basin, were investigated using different staining techniques and Fluorescent in situ hybridization with 5S and 18S rDNA probes. The diploid number was invariably 2n = 60 and the fundame
Genetics and Molecular Biology. Publicado em: 19/11/2008
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23. High levels of chromosomal differentiation in Euchroma gigantea L. 1735 (Coleoptera, Buprestidae)
Euchroma gigantea was karyotypically studied using conventional staining, C-banding, silver nitrate staining and ribosomal fluorescent in situ hybridization (rDNA FISH). Broad wide autosomal polymorphism and a complex sex determination system were found in this beetle. Karyotype complements ranging from 2n = 32, X1X2X3Y1Y2Y3 to 2n = 36,X1X2X3Y1Y2Y3 were dete
Genetics and Molecular Biology. Publicado em: 2008
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24. Cytotaxonomy and karyoevolution of the genus Crenicichla (Perciformes, Cichlidae)
Karyotypes of six cichlid species of the genus Crenicichla were investigated. The species C. cincta, C. inpa, C. reticulata, C. lugubris, and C. cf. johanna were collected from Amazon basin, and C. britskii was collected from the Paraná-Paraguai basin. All of the analysed species showed 2n = 48 chromosomes; however, C. cincta, C. lugubris, C. cf. johanna, a
Genetics and Molecular Biology. Publicado em: 2008