Nucleolar Organizer Regions Nors
Mostrando 1-12 de 42 artigos, teses e dissertações.
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1. Chromosomal characterization of Amazonian freshwater stingrays with evidence for new karyomorphs and XX/XY sex chromosomes
Abstract Cytogenetic studies in the subfamily Potamotrygoninae have provided valuable insights into the understanding of the evolution and diversification of its species. In the present study, the chromosomal features of seven nominal potamotrygonin species are provided: Plesiotrygon iwamae (2n=74, FN=120), Potamotrygon amazona (2n=66, FN=107), P. constellat
Genet. Mol. Biol.. Publicado em: 14/11/2019
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2. [PROVISIONAL] Does the chromosomal position of 35S rDNA sites influence their transcription? A survey on Nothoscordum species (Amaryllidaceae)
Abstract 35S ribosomal DNA (rDNA) sites are the regions where the ribosomal genes 18S, 5.8S and 25S, responsible for the formation of the nucleoli, are found. The fact that rDNA sites have non-random distribution on chromosomes suggests that their position on the chromosome may influence their transcription. In order to identify if the preferentially transcr
Genet. Mol. Biol.. Publicado em: 29/08/2019
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3. Análisis del cariotipo del híbrido natural Aloe x spinosissima y de sus parentales Aloe arborescens y Aloe humilis, mediante bandeo cromosómico C, CMA y DAPI
Abstract The karyotype of three species of Aloe was studied with C-Giemsa, CMA (Chromomycin A3) and DAPI (4'-6-diamino-2.fenildol) chromosome banding in order to make contributions in their cariomorfometría, location, size studied bands, and discuss cytogenetic evidence of hybrid origin reported in A. x spinossisima. The entities studied have a 2n = 2x = 14
Rodriguésia. Publicado em: 2017-09
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4. Cytogenetic studies in six species of Scinax (Anura, Hylidae) clade Scinax ruber from northern and northeastern Brazil
Scinax species are still underrepresented in cytogenetic studies, mainly with respect to populations from northeastern and northern Brazil. In this study, we provide new chromosomal information on Scinax boesemani, S. camposseabrai, S. garbei, S. pachycrus, S. trilineatus and S. x-signatus, all belonging to clade S. ruber. They were collected at two location
Genet. Mol. Biol.. Publicado em: 2015-06
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5. Genetic identification of bucktooth parrotfish Sparisoma radians (Valenciennes, 1840) (Labridae, Scarinae) by chromosomal and molecular markers
Parrotfishes (Labridae, Scarinae) comprise a large marine fish group of difficult identification, particularly during juvenile phase when the typical morphology and coloration of adults are absent. Therefore, the goal of this study was to test cytogenetic markers and DNA barcoding in the identification of bucktooth parrtotfish Sparisoma radians from the nort
Genet. Mol. Biol.. Publicado em: 14/11/2014
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6. Nucleolar organizer regions in Sittasomus griseicapillus and Lepidocolaptes angustirostris (Aves, Dendrocolaptidae): evidence of a chromosome inversion
Cytogenetic studies in birds are still scarce compared to other vertebrates. Woodcreepers (Dendrocolaptidae) are part of a highly specialized group within the Suboscines of the New World. They are forest birds exclusive to the Neotropical region and similar to woodpeckers, at a comparable evolutionary stage. This paper describes for the first time the karyot
Genet. Mol. Biol.. Publicado em: 2013
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7. Relação entre a quantidade de AgNORS, atividade proliferativa e o estágio de desenvolvimento placentário em equinos
As Regiões Organizadoras de Nucléolo (NORs - nucleolar organizer regions) são utilizadas para descrever regiões de cromatina coradas por Nitrato de Prata e estão relacionados com a atividade de síntese de RNAr e com a agilidade e rapidez na proliferação celular nos tecidos estudados. O objetivo deste trabalho foi relacionar a quantidade de AgNORs, a
Pesq. Vet. Bras.. Publicado em: 2012-12
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8. Cytogenetic divergence in two sympatric fish species of the genus Astyanax Baird and Girard, 1854 (Characiformes, Characidae) from northeastern Brazil
The fish genus Astyanax is widespread throughout the Neotropical region and is one of the most species-rich genera of the Characiformes. Cytogenetic studies of Astyanax have revealed marked intra-and interspecific diversity, with the identification of various species complexes. In this report, we describe the karyotypic structure of two sympatric species of
Genet. Mol. Biol.. Publicado em: 13/11/2012
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9. Cytogenetic characterization of F1, F2 and backcross hybrids of the Neotropical catfish species Pseudoplatystoma corruscans and Pseudoplatystoma reticulatum (Pimelodidae, Siluriformes)
The cytogenetic characteristics of Pseudoplatystoma corruscans and Pseudoplatystoma reticulatum and their F1, F2 and backcross hybrids were assessed by using chromosome banding techniques. The diploid number of 56 chromosomes was constant in all species and lineages, with a karyotypic formula containing 20 metacentric, 12 submetacentric, 12 subtelocentric an
Genetics and Molecular Biology. Publicado em: 02/02/2012
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10. Citotaxonomia de arraias de água doce (Myliobatiformes, Potamotrygonidae) da Bacia Amazônica Central
The family Potamotrygonidae in the order Myliobatiformes comprises all the Neotropical freshwater ray species. The knowledge about this fish group is limited, for example, the species number is uncertain, some species names are questionable, there is no information about how their diversification in freshwater happened, and there are no studies about their r
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 26/10/2011
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11. Nucleolus Organizer Regions chromatin architecture and its role in ribosomal genes expression / Arquitetura da cromatina na região organizadora do nucléolo e o seu papel no controle da expressão dos genes ribossomais
O nucléolo é uma organela nuclear responsável pela produção dos ribossomos, através das Regiões Organizadoras do Nucléolo (NORs). Espécies que possuem mais de um par de cromossomos contendo NORs terão, obrigatoriamente, pelo menos um par ativo, sendo as demais NORs funcionais de acordo com a demanda celular. O mecanismo de compensação de dose é
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 30/09/2011
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12. Estudos citogenéticos em espécies das tribos Hypostomini e Ancistrini (Loricariidae, Hypostominae)
Conventional and molecular cytogenetic analysis were performed on 15 species of the subfamily Hypostominae, comprising 12 species of the Hypostomini tribe, genus Hypostomus, and three of the Ancistrini tribe, genera Ancistrus and Hemiancistrus. The chromosome number of 2n=52 was observed for Ancistrus multispinis (14m+14sm+24st-a), A. brevipinnis (14m+14sm+2
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 02/09/2011