Consulta: subjectFacets:"Heterochromatin"
Registros recuperados: 34
Data/hora: 05/06/2024 14:22:55

Karyotype relationships among Anastrepha bistrigata, A. striata and A. serpentina (Diptera, Tephritidae)
Provedor de dados: 74
Autores: Selivon,Denise; Sipula,Fabiana Maria; Rocha,Lincoln S.; Perondini,André Luiz P.
The species of Anastrepha are arranged into 17 intrageneric groups. Recently, it was proposed that two species of the striata group, Anastrepha striata and A. bistrigata, might be realocated to serpentina group. Anastrepha bistrigata and A. serpentina have an X1X2Y/X1X1 X2X2 sex chromosome system while A. striata has a XY/XX system. It was previously proposed that the karyotype of A. bistrigata could be derived from that of A. striata by an Y:A fusion, and that the karyotype of A. serpentina would be derived from another, hypothetical karyotype. In the present report sequential staining with DAPI and chromomycin A3 (CMA3), followed by C-banding, revealed that the C-banded heterochromatic blocks of the sex chromosomes of A. bistrigata have different...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Flies; Mitotic chromosomes; Fluorochromes; Heterochromatin.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572007000600009

Chromosomal evidence of population subdivision in the freshwater fish Leporinus elongatus in the Upper Paraná River basin
Provedor de dados: 74
Autores: Molina,Wagner Franco; Shibatta,Oscar; Galetti Jr.,Pedro Manoel.
Cytogenetic analyses performed in populations of the Neotropical freshwater fish Leporinus elongatus of the Upper Paraná River basin showed a chromosome polymorphism involving heterochromatic segments of the nucleolar organizing pair in this species. The NOR-bearing chromosome pair was characterized by two phenotypes identified by the absence (C¹) or presence (C²) of a heterochromatic segment located in an interstitial position of the long arm in this pair. The meiotic segregation of these variations results in three distinct cytotypes, C¹C¹, C¹C² and C²C². Both populations were in Hardy-Weinberg equilibrium. Sex-related cytotype divergence was identified and multivariate analyses revealed that the C²C² individuals presented morphometric differentiation...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Characiformes; Anostomidae; Heterochromatin; Chromosome polymorphism.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572008000200020

Heterochromatin diversity and its co-localization with 5S and 45S rDNA sites in chromosomes of four Maxillaria species (Orchidaceae)
Provedor de dados: 74
Autores: Cabral,Juliano S.; Felix,Leonardo P.; Guerra,Marcelo.
We investigated four orchids of the genus Maxillaria (M. discolor, M. acicularis, M. notylioglossa and M. desvauxiana) in regard to the position of heterochromatin blocks as revealed using chromomycin A3 (CMA) and 4'-6-diamidino-2-phenylindole (DAPI) fluorochrome staining and 5S and 45S rDNA sites using fluorescence in situ hybridization (FISH). The species showed differences in chromosome number and a diversified pattern of CMA+ and DAPI+ bands, including heteromorphism for CMA+ bands. The 5S and 45S rDNA sites also varied in number and most of them were co-localized with CMA+ bands. The relationship between 5S rDNA sites and CMA+ bands was more evident in M. notylioglossa, in which the brighter CMA+ bands were associated with large 5S rDNA sites....
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Heterochromatin; CMA and DAPI; 45S and 5S rDNA; Maxillaria.
Ano: 2006
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572006000400015

A karyotypic study of three southern Brazilian Asteraceae species using fluorescence in situ hybridization with a 45S rDNA probe and C-CMA3 banding
Provedor de dados: 74
Autores: Fregonezi,Jéferson N.; Torezan,José M.D.; Vanzela,André L.L.
The Asteraceae, one of the largest families of flowering plants, contains about 1,100 genera and 20,000 species, and is well known for its extensive karyotypic variation. In this study, conventional Feulgen staining, C-CMA3 banding, and fluorescence in situ hybridization with a 45S rDNA probe were used to determine the chromosome number and the number and physical position of GC-rich heterochromatin and 45S rDNA sites in three Asteraceae weed species (Crepis japonica, Galinsoga parviflora and Chaptalia nutans). The three species exhibited karyotype differences in the chromosome number and shape, as a commom feature of Asteraceae. However, the 45S rDNA sites always occurred on the short chromosomal arms, associated with GC-heterochromatin. Althought of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: CMA3; FISH; Heterochromatin; Polyploidy; 45S rDNA.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572004000200016

Cytogenetic characterization of two species of Frieseomelitta Ihering, 1912 (Hymenoptera, Apidae, Meliponini)
Provedor de dados: 74
Autores: Carvalho,Antônio F.; Costa,Marco Antônio.
The cytogenetic analysis of Frieseomelitta dispar and F. francoi revealed the chromosome numbers 2n = 30 and n = 15 and a karyotypic formula 2K = 4M+2Mt+4A+20A M. The number of chromosomes observed was consistent with those reported for other Frieseomelitta species. The occurrence of the Mt chromosome and other features of the karyotype formulae suggest a close relationship between F. dispar, F. francoi and F. varia. Nevertheless, it was possible to differentiate the karyotypes of the species by DAPI/CMA3 staining, which revealed GC-rich regions on two chromosome pairs of F. dispar: one acrocentric and one pseudoacrocentric. In F. francoi, the same kinds of regions were observed on a pair of metacentrics and on a pair of acrocentrics. Our analysis also...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Hymenoptera; Frieseomelitta; Interspecific differentiation; C-banding; Heterochromatin.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572011000200012

A study of the constitutive heterochromatin and nucleolus organizer regions of Isocopris inhiata and Diabroctis mimas (Coleoptera: Scarabaeidae, Scarabaeinae) using C-banding, AgNO3 staining and FISH techniques
Provedor de dados: 74
Autores: Bione,Edgar; Camparoto,Marjori Leiva; Simões,Zilá Luz Paulino.
Meiotic and mitotic chromosomes of Isocopris inhiata and Diabroctis mimas were studied by standard staining procedures, C-banding, silver nitrate staining and FISH using Apis mellifera 28S rDNA as probe. Isocopris inhiata presented a 2n = 18 (8II+ Xy p) karyotype, composed of meta-submetacentric chromosomes with gradual reduction in size. The karyotype of D. mimas was 2n = 20 (9II+ Xy p), composed of meta-submetacentric (pairs 1, 2, 3, 4 and 7) and acrocentric (pairs 5, 6, 8 and 9) chromosomes, with gradual reduction in size. Analysis of constitutive heterochromatin revealed similar C-banding patterns for both species, showing pericentromeric and telomeric bands and diphasic chromosomes. In addition, the X chromosomes of these species were found to be...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Coleoptera; Heterochromatin; NORs; FISH.
Ano: 2005
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572005000100019

Cytogenetic studies in six species of Scinax (Anura, Hylidae) clade Scinax ruber from northern and northeastern Brazil
Provedor de dados: 74
Autores: Nogueira,Lídia; Zanoni,Juliani Bruna; Solé,Mirco; Affonso,Paulo Roberto Antunes de Mello; Siqueira,Sérgio; Sampaio,Iracilda.
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 locations in the Caatinga biome (northeastern Brazil) and at one in the Amazon (northern Brazil) biomes. Chromosomes were analyzed by conventional staining, C-banding, Ag-NOR staining, and fluorochrome staining. All species shared a modal diploid value of 2n = 24 and fundamental arm number (FN) of 48. Moreover, both chromosomal size and morphology were similar to other species in this Scinax clade. C-banding...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Amphibians; Chromosomes; Fluorochromes; Heterochromatin; RDNA.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572015000200156

Karyotype characterization of Trigona fulviventris Guérin, 1835 (Hymenoptera, Meliponini) by C banding and fluorochrome staining: report of a new chromosome number in the genus
Provedor de dados: 74
Autores: Domingues,Alayne Magalhães Trindade; Waldschmidt,Ana Maria; Andrade,Sintia Emmanuelle; Andrade-Souza,Vanderly; Alves,Rogério Marco de Oliveira; Silva Junior,Juvenal Cordeiro da; Costa,Marco Antônio.
Although many species of the genus Trigona have been taxonomically described, cytogenetic studies of these species are still rare. The aim of the present study was to obtain cytogenetic data by conventional staining, C banding and fluorochrome staining for the karyotype characterization of the species Trigona fulviventris. Cytogenetic analysis revealed that this species possesses a diploid chromosome number of 2n = 32, different from most other species of this genus studied so far. This variation was probably due to the centric fusion in a higher numbered ancestral karyotype, this fusion producing the large metacentric chromosome pair and the lower chromosome number observed in Trigona fulviventris. Heterochromatin was detected in the pericentromeric...
Tipo: Info:eu-repo/semantics/other
Palavras-chave: Cytogenetics; Heterochromatin; Evolution; Stingless bees.
Ano: 2005
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572005000300009

Karyotype and genome size comparative analyses among six species of the oilseed-bearing genus Jatropha (Euphorbiaceae)
Provedor de dados: 74
Autores: Marinho,Anne C.T.A.; Vasconcelos,Santelmo; Vasconcelos,Emanuelle V.; Marques,Daniela A.; Benko-Iseppon,Ana Maria; Brasileiro-Vidal,Ana Christina.
Abstract Jatropha is an important genus of Euphorbiaceae, with species largely used for various purposes, including the manufacturing of soaps and pharmaceutical products and applications in the bioenergetic industry. Although there have been several studies focusing J. curcas in various aspects, the karyotype features of Jatropha species are poorly known. Therefore, we analyzed six Jatropha species through fluorochrome staining (CMA/DAPI), fluorescent in situ hybridization (FISH) with 5S and 45S rDNA probes and genome size estimation by flow cytometry. Our results revealed several chromosome markers by both CMA/DAPI and FISH for the analyzed species. Five Jatropha species (J. curcas, J. gossypiifolia, J. integerrima, J. multifida and J. podagrica) showed...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Cytotaxonomy; DNA C-value; Heterochromatin; Physic nut; RDNA.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572018000300442

Karyotypic conservatism in samples of Characidium cf. zebra (Teleostei, Characiformes, Crenuchidae): physical mapping of ribosomal genes and natural triploidy
Provedor de dados: 74
Autores: Pansonato-Alves,José Carlos; Oliveira,Claudio; Foresti,Fausto.
Basic and molecular cytogenetic analyses were performed in specimens of Characidium cf. zebra from five collection sites located throughout the Tietê, Paranapanema and Paraguay river basins. The diploid number in specimens from all samples was 2n = 50 with a karyotype composed of 32 metacentric and 18 submetacentric chromosomes in both males and females. Constitutive heterochromatin was present at the centromeric regions of all chromosomes and pair 23, had additional interstitial heterochromatic blocks on its long arms. The nucleolar organizer regions (NORs) were located on the long arms of pair 23, while the 5S rDNA sites were detected in different chromosomes among the studied samples. One specimen from the Alambari river was a natural triploid and had...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Characidium; Heterochromatin; 18S rDNA; 5S rDNA; Natural triploidy.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572011000200007

The karyotype of Nothoscordum arenarium Herter (Gilliesioideae, Alliaceae): a populational and cytomolecular analysis
Provedor de dados: 74
Autores: Souza,Luiz G.R.; Crosa,Orfeo; Winge,Helga; Guerra,Marcelo.
The genus Nothoscordum Kunth comprises approximately 20 species native to South America. Karyologically, the genus is remarkable for its large chromosomes and Robertsonian translocations. Variation in chromosome number has been recorded in a few polyploid species and it is unknown among diploids. This study presents the chromosome number and morphology of 53 individuals of seven populations of N. arenarium Herter (2n = 10). In addition, karyotype analyses after C-banding, staining with CMA and DAPI, and in situ hybridization with 5S and 45S rDNA probes were performed in six individuals from one population. All individuals exhibited 2n = 10 (6M + 4A), except for one tetraploid (2n = 20, 12M + 8A) and one triploid (2n = 15, 9M + 6A) plant. C-banding revealed...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: CMA/DAPI staining; 5S and 45S rDNA; Heterochromatin; Nothoscordum; Robertsonian translocation.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572009000100016

B chromosomes in a population of Astyanax eigenmanniorum (Characiformes, Characidae) from the Araguari River Basin (Uberlândia, MG, Brazil)
Provedor de dados: 74
Autores: Torres-Mariano,Alessandra Ribeiro; Morelli,Sandra.
A cytogenetic study was conducted on an Astyanax eigenmanniorum population from the Caetano Stream (18° 44' 56" S/ 048° 18' 39" W) - in Uberlândia, MG, Brazil - showing a modal diploid number of 48 chromosomes in the standard male and female karyotypes. However, in several specimens it was also possible to observe metaphases with one or two B chromosomes, increasing the diploid number to 49 or 50 chromosomes, respectively. The supernumerary chromosomes were totally heterochromatic and highlighted after C-banding. The silver-stained nucleolus organizing regions (Ag-NORs) were located in at least five chromosomes of the standard karyotype, thus characterizing a multiple NOR system in the species. This is the first occurrence of an A. eigenmanniorum...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Characidae; Astyanax eigenmanniorum; Supernumerary chromosome; Heterochromatin; Nucleolus organizing regions (NORs).
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572008000200015

Comparative cytogenetics in three Melipona species (Hymenoptera: Apidae) with two divergent heterochromatic patterns
Provedor de dados: 74
Autores: Cunha,Marina Souza da; Travenzoli,Natália Martins; Ferreira,Riudo de Paiva; Cassinela,Edson Kuatelela; Silva,Henrique Barbosa da; Oliveira,Francisco Plácido Magalhães; Salomão,Tânia Maria Fernandes; Lopes,Denilce Meneses.
Abstract The genus Melipona is subdivided into four subgenera based on morphological characteristics, and two groups based on cytogenetic patterns. The cytogenetic information on this genus is still scarce, therefore, the goal of this study was to characterize Melipona paraensis, Melipona puncticollis, and Melipona seminigra pernigra using the following techniques: C-banding, DAPI/CMA3 fluorochromes, and FISH with an 18S rDNA probe. Melipona paraensis (2n=18) and M. seminigra pernigra (2n=22) were classified as high heterochromatin content species (Group II). Their euchromatin is restricted to the ends of the chromosomes and is CMA3+; the 18S rDNA probe marked chromosome pair number 4. Melipona puncticollis (2n=18) is a low heterochromatin content species...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Chromosomal evolution; DAPI/CMA3 fluorochromes; Fluorescent in situ Hybridization (FISH); Heterochromatin; Meliponini.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572018000500806

Karyotype differentiation of four Cestrum species (Solanaceae) revealed by fluorescent chromosome banding and FISH
Provedor de dados: 74
Autores: Fernandes,Thiago; Rego,Letícia do Nascimento Andrade de Almeida; Nardy,Mariana; Yuyama,Priscila Mary; Vanzela,André Luís Laforga.
The karyotypes of four South American species of Cestrum (C. capsulare, C. corymbosum, C. laevigatum and C. megalophylum) were studied using conventional staining, C-CMA/DAPI chromosome banding and FISH with 45S and 5S rDNA probes. The karyotypes showed a chromosome number of 2n = 2x = 16, with metacentric chromosomes, except for the eighth submeta- to acrocentric pair. Several types of heterochromatin were detected, which varied in size, number, distribution and base composition. The C-CMA+ bands and 45S rDNA were located predominantly in terminal regions. The C-CMA+/DAPI+ bands appeared in interstitial and terminal regions, and the C-DAPI+ bands were found in all chromosome regions. The 5S rDNA sites were observed on the long arm of pair 8 in all species...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Cestrum; Chromosome banding; FISH; Heterochromatin; Physical maps; 45S and 5S rDNA.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572009000200019

Hypomethylation of cytosine residues in cold-sensitive regions of Cestrum strigilatum (Solanaceae)
Provedor de dados: 74
Autores: Guarido,Paula Carolina Paes; Paula,Adriano Alves de; Silva,Carlos Roberto Maximiano da; Rodriguez,Carmen; Vanzela,André Luís Laforga.
Heterochromatin comprises a fraction of the genome usually with highly repeated DNA sequences and lacks of functional genes. This region can be revealed by using Giemsa C-banding, fluorochrome staining and cytomolecular tools. Some plant species are of particular interest through having a special type of heterochromatin denominated the cold-sensitive region (CSR). Independent of other chromosomal regions, when biological materials are subjected to low temperatures (about 0 °C), CSRs appear slightly stained and decondensed. In this study, we used Cestrum strigilatum (Solanaceae) to understand some aspects of CSR condensation associated with cytosine methylation levels, and to compare the behavior of different heterochromatin types of this species, when...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Anti-5-methylcytosine; Cestrum; Chromosomes; CMA/DAPI banding; Heterochromatin; Immunolabeling.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572012000300012

Karyotype and nuclear DNA content of hexa-, octo-, and duodecaploid lines of Bromus subgen. Ceratochloa
Provedor de dados: 74
Autores: Klos,Joanna; Sliwinska,Elwira; Kula,Adam; Golczyk,Hieronim; Grabowska-Joachimiak,Aleksandra; Ilnicki,Tomasz; Szostek,Krzysztof; Stewart,Alan; Joachimiak,Andrzej J.
The subgenus Ceratochloa of the genus Bromus includes a number of closely related allopolyploid forms or species that present a difficult taxonomic problem. The present work combines data concerning chromosome length, heterochromatin distribution and nuclear genome size of different 6x, 8x and 12x accessions in this subgenus. Special attention is paid to the karyotype structure and genomic constitution of duodecaploid plants recently found in South America. Hexaploid lineages possess six almost indistinguishable genomes and a nuclear DNA content between 12.72 pg and 15.10 pg (mean 1Cx value = 2.32 pg), whereas octoploid lineages contain the same six genomes (AABBCC) plus two that are characterized by longer chromosomes and a greater DNA content (1Cx = 4.47...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Karyotype; C-banding; Heterochromatin; Flow cytometry; Genome size.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572009000300016

A remarkable autosomal heteromorphism in Pseudoryzomys simplex 2n = 56; FN = 54-55 (Rodentia, Sigmodontinae)
Provedor de dados: 74
Autores: Moreira,Camila Nascimento; Di-Nizo,Camilla Bruno; Silva,Maria José de Jesus; Yonenaga-Yassuda,Yatiyo; Ventura,Karen.
Pseudoryzomys simplex, the false rice rat, is a monotypic genus of the Oryzomyini tribe (Sigmodontinae) distributed in part of Bolivia, Paraguay, Argentina and Brazil. Its diploid number has been described as 56 acrocentric chromosomes decreasing in size and no karyotype figure has been depicted. Herein, we present karyotypic data on P. simplex, including chromosome banding and molecular fluorescent in situ hybridization using telomeric sequences and the whole X-chromosome of its sister clade Holochilus brasiliensis (HBR) as probes. A case of remarkable autosomal heteromorphism due to the presence of a whole heterochromatic arm leading to the variability of FN is reported, as well as the occurrence of regions of homology between the X and Y chromosomes...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Cytogenetics; Fluorescent in situ hybridization; Heterochromatin; Oryzomyini.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572013000200010

Cytogenetics of three Brazilian species of Eleutherodactylus (Anura, Leptodactylidae) with 22 chromosomes and re-analysis of multiple translocations in E. binotatus
Provedor de dados: 74
Autores: Siqueira-Jr.,Sérgio; Ananias,Fernando; Recco-Pimentel,Shirlei M.
In this paper, we provide a cytogenetic analysis of Eleutherodactylus guentheri, E. parvus and E. binotatus. All of the species had a diploid chromosomal number of 2n = 22. The karyotypes of E. guentheri and E. parvus were very similar and differed only slightly in the morphology of pair 2. These two species also had an NOR-bearing secondary constriction on the long arms of pair 6. The karyotype of E. binotatus differed from those of E. guentheri and E. parvus in the morphology and size of the chromosomes, in the number of chromosomal arms, in the NOR location (detected on the short arms of pair 1), and in the pattern of heterochromatin. These results reinforce the differences between E. guentheri and E. binotatus and support the existence of two species...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Eleutherodactylus; Heterochromatin; Karyotype; Nucleolus organizing region (NOR); Reciprocal translocation.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572004000300010

Satellite DNA sites in four species of the genus Astyanax (Teleostei, Characiformes)
Provedor de dados: 74
Autores: Kavalco,Karine Frehner; Pazza,Rubens; Bertollo,Luiz Antonio Carlos; Moreira-Filho,Orlando.
Cytogenetic data about satellite DNA distribution in four Astyanax species (Characidae) from the Paraitinga river, Paraíba do Sul river basin, Brazil, are presented. In order to characterize the constitutive heterochromatin, C-banding, chromomycin A3 and DAPI fluorescence staining, as well as fluorescence in situ hybridization (FISH) with the satellite DNA As-51 probe were performed. A. scabripinnis and A. parahybae presented 2n = 50 and 2n = 48 chromosomes, respectively. The heterochromatin was located in the pericentromeric and terminal regions of many chromosomes, corresponding to GC-positive regions and to the As-51 satellite DNA in terminal regions. A. intermedius and A. giton, both with 2n = 50 chromosomes, showed little heterochromatin, mostly...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Astyanax; Fluorescence in situ hybridization (FISH); Heterochromatin; Karyotypic diversity; Satellite DNA.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572007000400005

Comparative cytogenetics of three species of Dichotomius (Coleoptera, Scarabaeidae)
Provedor de dados: 74
Autores: Silva,Guilherme Messias da; Bione,Edgar Guimarães; Cabral-de-Mello,Diogo Cavalcanti; Moura,Rita de Cássia de; Simões,Zilá Luz Paulino; Souza,Maria José de.
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 karyotype with 2n = 18 and meta-submetacentric chromosomes. The sex determination mechanism was of the Xy p type in D. nisus and D. semisquamosus and of the Xyr type in D. sericeus. C-banding revealed the presence of pericentromeric blocks of constitutive heterochromatin (CH) in all the chromosomes of the three species. After silver staining, the nucleolar organizer regions (NORs) were located in...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Chromosome rearrangements; Heterochromatin; Karyotype; NORs; FISH.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572009000200012

Chromatin differentiation between Theobroma cacao L. and T. grandiflorum Schum
Provedor de dados: 74
Autores: Dantas,Liliane G.; Guerra,Marcelo.
A comparative analysis of mitotic chromosomes of Theobroma cacao (cacao) and T. grandiflorum (cupuaçu) was performed aiming to identify cytological differences between the two most important species of this genus. Both species have symmetric karyotypes, with 2n = 20 metacentric chromosomes ranging in size from 2.00 to 1.19 µm (cacao) and from 2.21 to 1.15 mm (cupuaçu). The interphase nuclei of both species were of the arreticulate type, displaying up to 20 chromocentres, which were more regularly shaped in cacao than in cupuaçu. Prophase chromosomes of both species were more condensed in the proximal region, sometimes including the whole short arm. Both species exhibited only one pair of terminal heterochromatic bands, positively stained with chromomycin...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Cacao; Cupuaçu; Heterochromatin; Karyotype; RDNA sites; Theobroma.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572010000100017

Chromosomal characterization of Pseudonannolene strinatii (Spirostreptida, Pseudonannolenidae)
Provedor de dados: 76
Autores: Campos,Kleber Agari; Fontanetti,Carmem S.
The chromosomes of the cave millipede Pseudonannolene strinatii Mauriès, 1974 were investigated. The diploid chromosome number was found to be 2n=16, XX/XY; the C-banding technique revealed a large amount of heterochromatin while the silver staining technique (Ag-NOR) evidenced the presence of heteromorphism of the NORs in some cells.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Diplopoda; Cytogenetics; Caves; Heterochromatin.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0073-47212004000100009

Karyotype characterization of Anastrepha fruit flies (Diptera: Tephritidae)
Provedor de dados: 82
Autores: Selivon,Denise; Perondini,André L.P.; Rocha,Lincoln S.
The study comprises the description of the C-banded mitotic chromosomes of five species of Anastrepha, A. amita Zucchi, A. turpiniae Stone, A. zenildae Zucchi, A. grandis (Macquart) and A. leptozona Hendel , and a reanalysis of the chromosomes of three other species, A. distincta Greene, A. obliqua (Macquart) and A. sororcula Zucchi. The species have a diploid number of 12, while A. leptozona has 2n = 10. Heteromorphism of the sex chromosomes is present in all of the species, which have a XY/XX sex chromosome system. A. grandis and A. leptozona have meta and submetacentric autosomes while all of the chromosomes in the other species are acrocentric. The species can be characterized unequivocally by the length and the pattern of blocks of heterochromatin in...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Heterochromatin; Mitotic chromosomes; Sex chromosomes; C-band.
Ano: 2005
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1519-566X2005000200015

Diversity and chromosomal evolution in the genusAncistrusKner, 1854 (Loricariidae: Ancistrini) from three hydrographic basins of Mato Grosso State, Brazil
Provedor de dados: 83
Autores: Mariotto,Sandra; Centofante,Liano; Moreira-Filho,Orlando.
Cytogenetic analyses were carried out in 117 specimens of seven species of the genus Ancistrus from three hydrographic in Mato Grosso State: Paraguay, Araguaia-Tocantins and Amazon basins. Conventional cytogenetic techniques were used to obtain mitotic chromosomes. C-banding was performed to detect heterochromatic regions and silver nitrate staining was used to identify nucleolar organizer regions (Ag-NORs). The counted and paired chromosomes revealed diploid numbers ranging from 2n = 40 to 2n = 54 with karyotype formulae varying from FN = 80 to FN = 86. Single marks in distinct chromosomes identified the nucleolar organizer regions. The constitutive heterochromatin was scarce in the diploid number from 2n = 50 to 2n = 54 and conspicuous blocks were...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: AgNOR; Cytogenetic; Diploid number; Heterochromatin.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252013000100125

Chromosomal characterization of the bonytongue Arapaima gigas (Osteoglossiformes: Arapaimidae)
Provedor de dados: 83
Autores: Marques,Debora Karla; Venere,Paulo Cesar; Galetti Junior,Pedro Manoel.
The mitotic chromosomes of the pirarucu Arapaima gigas inhabiting the middle Araguaia River and collected in the municipality of Araguaiana (MT, Brazil) were studied. The chromosomes were analyzed through Giemsa staining, C-banding, Ag-NOR staining and in situ hybridization using an 18S rRNA gene probe. The karyotype had 2n=56 comprising 14 biarmed and 14 uniarmed chromosome pairs in both sexes. No cytologically distinguishable sex chromosome was identified. A single NOR-bearing chromosome pair was detected by Ag-NOR staining and confirmed by 18S rDNA- FISH. Faint constitutive heterochromatin was C-banded in the centromeric region of some chromosomes.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Pirarucu; Karyotype; RDNA; Heterochromatin.
Ano: 2006
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252006000200007

Karyotype differentiation and cytotaxonomic considerations in species of Serrasalmidae (Characiformes) from the Amazon basin
Provedor de dados: 83
Autores: Nakayama,Celeste Mutuko; Feldberg,Eliana; Bertollo,Luiz Antonio Carlos.
Six species of Serrasalmidae from the central Amazon, representatives of the genera Serrasalmus (S. elongatus, S. maculatus, S. cf. rhombeus, and S. rhombeus), Pygocentrus (P. nattereri), and Colossoma (C. macropomum), were analyzed regarding the distribution of the Ag-NORs, C-positive heterochromatin and 18S and 5S rRNA genes on the chromosomes. All specimens had 2n = 60 chromosomes, except S. cf. rhombeus, with 2n = 58, and C. macropomum with 2n = 54 chromosomes. The Ag-NORs were multiple and located on the short arms of subtelo-acrocentric chromosomes in all Serrasalmus species and in P. nattereri, but were found on metacentric chromosomes in C. macropomum. The 18S rDNA sites were usually coincident with Ag-NORs, although some species had a higher...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Chromosomal evolution; Fish; Heterochromatin; Piranhas; Ribosomal genes.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252012000100005

Identification of distinct evolutionary units in allopatric populations of Hypostomus cf. wuchereri Günther, 1864 (Siluriformes: Loricariidae): karyotypic evidence
Provedor de dados: 83
Autores: Bitencourt,Jamille de Araújo; Affonso,Paulo Roberto Antunes de Mello; Giuliano-Caetano,Lucia; Dias,Ana Lucia.
Few chromosomal reports are available for the endemic fish fauna from coastal basins in northeastern Brazil, and regional biodiversity remains partially or completely unknown. This is particularly true for Loricariidae, the most diverse family of armored catfishes. In the present work, allopatric populations of Hypostomus cf. wuchereri (Siluriformes: Loricariidae) from two basins in Bahia (northeastern Brazil) were cytogenetically analyzed. Both populations shared 2n = 76 chromosomes, a karyotype formula of 10m+18sm+48st/a (FN = 104) and single terminal GC-rich NORs on the second metacentric pair. Nevertheless, microstructural differences were detected by C-banding, fluorochrome staining and chromosomal digestion with restriction enzymes (Alu I, Bam HI,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Biodiversity; Cytogenetics; Heterochromatin; Hypostominii.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252011000200008

Cytogenetic study of two species of the family Pimelodidae (Siluriformes) collected in lago Guaíba, Rio Grande do Sul, Brazil
Provedor de dados: 83
Autores: Treco,Fernando Rodrigo; Malabarba,Luiz R.; Giuliano-Caetano,Lucia; Dias,Ana Lúcia.
A cytogenetic study was conducted on specimens of Parapimelodus nigribarbis and Pimelodus maculatus collected in the lago Guaíba drainage, Porto Alegre, Rio Grande do Sul, Brazil. The two species had a diploid number of 56 chromosomes, with P. nigribarbis showing a karyotype of 20m + 20sm + 4st + 12a with FN of 100, and P. maculatus showing a karyotype of 24m + 20sm + 6st + 6a with FN of 106. NORs were demonstrated in both species in only one pair of subtelocentric chromosomes, in the terminal region of the long arm, which was coincident with C- banding and CMA3 staining, while DAPI staining was negative in these regions. Parapimelodus nigribarbis had a greater number of heterochromatic bands than did P. maculatus, which were distributed mainly in the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Parapimelodus; Pimelodus; NOR; Heterochromatin; Fluorochromes.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252008000100010

Cytogenetic characterization of Hypostomus nigromaculatus (Siluriformes: Loricariidae)
Provedor de dados: 83
Autores: Rubert,Marceléia; Zawadzki,Cláudio H.; Giuliano-Caetano,Lucia.
Hypostomus is the most speciose genus in the family Loricariidae, with approximately 120 species. These fish show a wide morphological and color variation, which hinders the identification of species, mainly of widely distributed representatives. The aim of this study was to contribute to the current knowledge on cytogenetic features of Hypostomus nigromaculatus. Three specimens of H. nigromaculatus, collected in two tributaries of rio Tibagi, Paraná, and in Cachoeira de Emas, rio Mogi-Guaçu, São Paulo, the latter being the type locality of H. nigromaculatus, were studied. Chromosomal preparations were submitted to Giemsa staining, silver nitrate impregnation, C-banding and CMA3 and DAPI fluorochromes staining. All samples presented 2n = 76, but the rio...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Karyotype evolution; Nucleolus organizer region; Heterochromatin; Hypostominae.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252008000100011

Chromosome analysis in Saccodon wagneri (Characiformes) and insights into the karyotype evolution of Parodontidae
Provedor de dados: 83
Autores: Nirchio,Mauro; Masache,Maria Cecilia; Paim,Fabilene Gomes; Cioffi,Marcelo de Bello; Moreira Filho,Orlando; Barriga,Ramiro; Oliveira,Claudio; Rossi,Anna Rita.
ABSTRACT Parodontidae is a relatively small group of Neotropical characiform fishes consisting of three genera (Apareiodon, Parodon, and Saccodon) with 32 valid species. A vast cytogenetic literature is available on Apareiodon and Parodon, but to date, there is no cytogenetic data about Saccodon, a genus that contains only three species with a trans-Andean distribution. In the present study the karyotype of S. wagneri was described, based on both conventional (Giemsa staining, Ag-NOR, C-bands) and molecular (repetitive DNA mapping by fluorescent in situ hybridization) methods. A diploid chromosome number of 2n = 54 was observed in both sexes, and the presence of heteromorphic sex chromosomes of the ZZ/ZW type was detected. The W chromosome has a terminal...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Ag-NOR; Cytogenetics; FISH; Heterochromatin; ZW sex chromosomes.
Ano: 2021
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252021000100203

Karyotype characterization and ZZ/ZW sex chromosome heteromorphism in two species of the catfish genus Ancistrus Kner, 1854 (Siluriformes: Loricariidae) from the Amazon basin
Provedor de dados: 83
Autores: Oliveira,Renildo R. de; Feldberg,Eliana; Anjos,Maeda B. dos; Zuanon,Jansen.
We present karyotypic characteristics and report on the occurrence of ZZ/ZW sex chromosomes in Ancistrus ranunculus (rio Xingu) and Ancistrus sp. "Piagaçu" (rio Purus), of the Brazilian Amazon. Ancistrus ranunculus has a modal number of 2n=48 chromosomes, a fundamental number (FN) of 82 for both sexes, and the karyotypic formula was 20m+8sm+6st+14a for males and 19m+9sm+6st+14a for females. Ancistrus sp. "Piagaçu" presented 2n=52 chromosomes, FN= 78 for males and FN= 79 for females. The karyotypic formula was 16m+8sm+2st+26a for males and 16m+9sm+2st+25a for females. The high number of acrocentric chromosomes in karyotype of Ancistrus sp. "Piagaçu" differs from the majority of Ancistrini genera studied so far, and may have resulted from pericentric...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Hypostominae; Ancistrini; Cytogenetics; Evolution; Heterochromatin.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252007000300010

Karyotype characterization and evolution of chromosome number in Cactaceae with special emphasis on subfamily Cactoideae
Provedor de dados: 39
Autores: Castro,Juliana P.; Moraes,Ana Paula; Chase,Mark W.; Santos,Angeline M. S.; Batista,Fabiane R. C.; Felix,Leonardo P.
ABSTRACT Cactaceae species are karyotypically well-known with x = 11 and chromosome number variation due mainly to polyploidization. However, both assumptions are based on descriptive observations without taking an evolutionary framework of Cactaceae into account. Aiming to confirm these hypotheses in an evolutionary context, we obtained chromosome numbers for 20 species of Cactoideae, performed an extensive review of chromosome number for the family, and analyzed these data using a phylogenetic approach. The karyotypes presented here were characterized by CMA/DAPI banding, and for six species 5S and 45S rDNA sites were located. Our data, along with a survey of the literature, reinforce the long-standing hypothesis of a x = 11 as the base chromosome number...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Base chromosome number; CMA/DAPI; Dysploidy; Heterochromatin; Polyploidy; RDNA.
Ano: 2020
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062020000100135

Evidence of separate karyotype evolutionary pathway in Euglossa orchid bees by cytogenetic analyses
Provedor de dados: 42
Autores: FERNANDES,ANDERSON; WERNECK,HUGO A.; POMPOLO,SILVIA G.; LOPES,DENILCE M.
Euglossini are solitary bees considered important pollinators of many orchid species. Information regarding chromosome organization is available for only a small number of species in this group. In the present work, the species Euglossa townsendi and E. carolina were analyzed by cytogenetic techniques to collect information that may aid the understanding of their evolution and chromosomal organization. The chromosome number found was n = 21 for males and 2n = 42 for females in the two species. The distribution and amount of heterochromatin regions differed in the two species analyzed, where they were classified as “high” or “low” heterochromatin content, similarly to what has already been performed in social bee species of the genus Melipona. Banding...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Cytogenetics; Euglossini; Heterochromatin; Karyotypic evolution.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652013000300937

Chromosome differentiation in three species of Leptostemonum (Solanum, Solanaceae) endemic to oceanic islands
Provedor de dados: 51
Autores: Chiarini,Franco E; Gauthier,Martha J.
The chromosomes of Solanum nelsonii, S. sandwicense (endemic to the Hawaii islands) and S. vespertilio (from the Canary islands) were studied by means of classical staining, CMA/DAPI banding and FISH with probes for the 18-5.8-26S and 5S rDNA genes. The aim of this study was to test for chromosomal changes (chromosome number, karyotype, heterochromatin pattern, rDNA loci) during the evolution of these taxa with respect to their continental relatives. An apparent chromosome stasis was confirmed in all three species, in regards to chromosome number and karyotype morphology. However, there was also evidence of cryptic, cumulative sequence changes. Speciation in these species is not likely associated with large, obvious chromosome rearrangements or polyploidy,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Chromosome stasis; Heterochromatin; Ribosomal DNA; Solanum subgen; Leptostemonum.
Ano: 2016
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S1851-23722016000200009