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| Maffei,Eliane Mariza Dortas; Pompolo,Silvia das Graças; Petitpierre,Eduard. |
| The aim of this study was to describe mitotic and meiotic chromosomes of Cycloneda sanguinea using C-banding, fluorescent in situ hybridization (FISH) rDNA probes, and sequential FISH/Ag-NOR staining. The chromosome number was 2n = 18 + XX for females and 2n = 18 + Xy for males. The X chromosome was metacentric and the Y chromosome was very small. During meiosis, the karyotypic meioformula was n = 9 + Xy p, and sex chromosomes configured a parachute at metaphase I. At the beginning of pachytene, bivalents were still individualized, and sex chromosomes were associated end-to-end through the heteropycnotic region of the X chromosome. Later in pachytene, further condensation led to the formation of a pseudo-ring by the sex bivalent. All chromosomes showed... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: In situ hybridization; RDNA sequences; Sequential FISH/Ag-NOR staining; C-banding; Cycloneda sanguinea. |
| Ano: 2004 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572004000200011 |
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| Marthe,Jefferson de Brito; Pompolo,Silvia das Graças; Campos,Lucio Antônio de Oliveira; Salomão,Tânia Maria Fernandes; Tavares,Mara Garcia. |
| Four colonies of the stingless bee Partamona cupira (Hymenoptera: Apidae) were cytogenetically analyzed using conventional staining and the fluorochromes CMA3 e DAPI. The females have 2n = 34 chromosomes (2K=32<img border=0 src="../../../../../../../img/revistas/gmb/2010nahead/ah06a04CarM.gif" align=absmiddle>+2<img border=0 src="../../../../../../../img/revistas/gmb/2010nahead/ah06a04CarA.gif" align=absmiddle>). Some females, however, presented an additional large B acrocentric chromosome, to a total of 2n = 35. Chromosome B and the chromosomal pairs 2, 9 and 10 showed CMA3+ bands, indicating an excess of CG base-pairs. A clear association was verified between the P. helleri B chromosome SCAR marker and the presence of a B chromosome in P.... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: B chromosome; SCAR; Stingless bees. |
| Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572010000200009 |
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| Scher,Ricardo; Pompolo,Silvia das Graças. |
| Cytogenetic analysis based on the distribution of C-bands showed two groups of karyotypes in a Trypoxylon nitidum population from the Rio Doce Park, State of Minas Gerais, Brazil. One of these groups, that was identical to a previously described karyotype (n = 15; 2n = 30), had a stable chromosome number and was rich in acrocentric chromosomes, whereas the other had a variable chromosome number (n = 12 to 14; 2n = 25 to 28) and was rich in pseudo-acrocentric chromosomes. We propose a hypothesis explaining the dynamics of the modifications which occurred in the karyotype of this species, based on the minimum interaction theory of Imai et al. (1986, 1988, 1994) and on the chromosome rearrangements and heteromorphisms observed by us. |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: C-banding; Trypoxylon nitidum; Karyotype evolution. |
| Ano: 2003 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572003000300015 |
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| Rocha,Marla Piumbini; Pompolo,Silvia das Graças. |
| We describe the karyotypes of eight bee species of the genus Melipona and compare them in terms of heterochromatin content and location (C-banding technique). All species had 2n = 18 (females) and n = 9 (males) chromosomes, but a wide variation in heterochromatin content was detected among karyotypes. On the basis of these differences, the species were divided into two functional groups, one of them comprising species with a karyotype having a low heterochromatin content (M. bicolor bicolor, M. quadrifasciata, M. marginata, and M. asilvai), and the other species with a high heterochromatin content (M. seminigra fuscopilosa, M. capixaba, M. scutellaris, and M. captiosa). In the species with high heterochromatin content, heterochromatin occupied practically... |
| Tipo: Info:eu-repo/semantics/article |
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| Ano: 1998 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47571998000100008 |
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| Krinski,Diones; Fernandes,Anderson; Rocha,Marla Piumbini; Pompolo,Silvia das Graças. |
| The aim was to broaden knowledge on the cytogenetics of the subtribe Meliponina, by furnishing cytogenetic data as a contribution to the characterization of bees from the genus Oxytrigona. Individuals of the species Oxytrigona cf. flaveola, members of a colony from Tangará da Serra, Mato Grosso State, Brazil, were studied. The chromosome number was 2n = 34, distributed among four chromosomal morphologies, with the karyotype formula 8m+8sm+16st+2t. Size heteromorphism in the first metacentric pair, subsequently confirmed by sequential staining with fluorochrome (DA/DAPI/CMA3), was apparent in all the examined individuals The nucleolar organizing regions (NORs) are possibly located in this metacentric chromosome pair. These data will contribute towards a... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chromosome; Heteromorphism; Fluorochrome. |
| Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572010000300020 |
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| Barth,Adriane; Fernandes,Anderson; Pompolo,Silvia das Graças; Costa,Marco Antônio. |
| Tetragonisca angustula and Tetragonisca fiebrigi have recently been listed as valid species. This study aimed to cytogenetically investigate both species, emphasizing the new registry of B chromosomes in the tribe Meliponini. We analyzed colonies of T. angustula and T. fiebrigi collected at Tangará da Serra, Mato Grosso, Brazil, through conventional Giemsa staining, C-banding, and base-specific fluorochrome staining (CMA3/DAPI). T. angustula showed 2n = 34 chromosomes in females and n = 17 in males, with karyotype formula 2K = 34A M. T. fiebrigi showed numeric variation, with chromosome number varying from 2n = 34 to 2n = 36 in females and from n = 17 to n=18in males, with karyotype formula 2K = 32A M+2A Mc and 2K = 32A M+2A Mc + 1 or 2 B-chromosomes. The... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Stingless bees; Cytogenetics; Interspecific differentiation; B chromosomes. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572011000100014 |
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