Consulta: creatorFacets:"Foresti,Fausto"
Registros recuperados: 52
Data/hora: 02/06/2024 05:36:49

Cytogenetic markers as diagnoses in the identification of the hybrid between Piauçu (Leporinus macrocephalus) and Piapara (Leporinus elongatus)
Provedor de dados: Genetics and Molecular Biology
Autores: Porto-Foresti,Fábio; Hashimoto,Diogo Teruo; Alves,Anderson Luis; Almeida,Rodrigo Braz Castilho; Senhorini,José Augusto; Bortolozzi,Jehud; Foresti,Fausto.
The genetic monitoring of interspecific hybrids involves the application of methodologies able to provide an easy and indubitable genetic characterization of both parental and hybrid individuals. In the present work, cytogenetic techniques were used to identify a hybrid lineage of "Piaupara" in order to caracterize them in relation to the parental species, Leporinus macrocephalus (piauçu) and L. elongatus (piapara). The cytogenetic analysis revealed that L. macrocephalus presented 2n = 54 chromosomes and a nucleolar organizer regions (NOR) at the telomere of the long arm of the submetacentric chromosome pair 2. Analysis of constitutive heterochromatin (C-banding) revealed a conspicuous block at the pericentromeric region on the long arm of a submetacentric...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Interspecific hybrid; Fish culture; Fish cytogenetics.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572008000200005

Cytogenetic characterization of F1, F2 and backcross hybrids of the Neotropical catfish species Pseudoplatystoma corruscans and Pseudoplatystoma reticulatum (Pimelodidae, Siluriformes)
Provedor de dados: Genetics and Molecular Biology
Autores: Prado,Fernanda Dotti do; Nunes,Tatiana Leite; Senhorini,José Augusto; Bortolozzi,Jehud; Foresti,Fausto; Porto-Foresti,Fábio.
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 and 12 acrocentric chromosomes. Nucleolar organizer regions (NORs) were identified in two subtelocentric chromosomes in the parents and hybrids, with partial nucleolar dominance in F1 and F2 specimens. Heterochromatic blocks were detected in the terminal and centromeric regions of some chromosomes in all individuals. For parental and hybrid lineages, 18S ribosomal clusters corresponding to NORs and 5S...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Backcrossing; Cytogenetics; Interspecific hybrids; Post-F1 hybrids; Pseudoplatystoma.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572012000100008

Discrimination of Shark species by simple PCR of 5S rDNA repeats
Provedor de dados: Genetics and Molecular Biology
Autores: Pinhal,Danillo; Gadig,Otto BF; Wasko,Adriane P; Oliveira,Claudio; Ron,Ernesto; Foresti,Fausto; Martins,Cesar.
Sharks are suffering from intensive exploitation by worldwide fisheries leading to a severe decline in several populations in the last decades. The lack of biological data on a species-specific basis, associated with a k-strategist life history make it difficult to correctly manage and conserve these animals. The aim of the present study was to develop a DNA-based procedure to discriminate shark species by means of a rapid, low cost and easily applicable PCR analysis based on 5S rDNA repeat units amplification, in order to contribute conservation management of these animals. The generated agarose electrophoresis band patterns allowed to unequivocally distinguish eight shark species. The data showed for the first time that a simple PCR is able to...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Chondrichthyes; PCR; Species identification; 5S rDNA; Sharks.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572008000200033

First report of a B chromosome in a natural population of Astyanax altiparanae (Characiformes, Characidae)
Provedor de dados: Genetics and Molecular Biology
Autores: Hashimoto,Diogo Teruo; Gonçalves,Vanessa Regina; Bortolozzi,Jehud; Foresti,Fausto; Porto-Foresti,Fábio.
Several species of the genus Astyanax have already been genetically studied, and B-chromosomes have been considered to be an interesting feature in some species of this group. In the present paper we report, for the first time, the occurrence of a B microchromosome in a natural population of A. altiparanae. This additional genomic element was identified as an acrocentric chromosome, similar in size to the smallest chromosomal pairs of the standard karyotype. Analysis of the constitutive heterochromatin pattern by C-banding evidenced heterochromatic blocks located on centromeric, pericentromeric, and interstitial regions of some chromosomes, and also positive marks in a subtelocentric chromosomal pair that presented the short arms entirely heterochromatic....
Tipo: Info:eu-repo/semantics/article
Palavras-chave: B chromosomes; Fish cytogenetics; Astyanax altiparanae.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572008000200021

Phylogenetic analysis of the order Pleuronectiformes (Teleostei) based on sequences of 12S and 16S mitochondrial genes
Provedor de dados: Genetics and Molecular Biology
Autores: Azevedo,Marisa F.C.; Oliveira,Claudio; Pardo,Belén G.; Martínez,Paulino; Foresti,Fausto.
The fish order Pleuronectiformes, composed of 14 families, has two suborders: Psettodoidei (with one family) and Pleuronectoidei (with thirteen families). The relationships among families of Pleuronectoidei and among the genera of their families have extensively been debated and a consensus has not yet been reached. In the present study, partial sequences of the 12S and 16S mitochondrial rRNA genes were obtained from 19 species belonging to the families Achiridae, Bothidae, Cynoglossidae, Paralichthyidae, Pleuronectidae, Scophthalmidae, and Soleidae. Additional sequences of 42 pleuronectiform species were obtained from GenBank. Phylogenetic analyses were conducted by the methods of maximum-parsimony, maximum-likelihood and Bayesian inference. Our results...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Phylogeny; Molecular systematics; Mitochondrial DNA; Fish evolution; Flatfishes.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572008000200023

Cytogenetic analysis of five species of the subfamily Corydoradinae (Teleostei: Siluriformes: Callichthyidae)
Provedor de dados: Genetics and Molecular Biology
Autores: Shimabukuro-Dias,Cristiane Kioko; Oliveira,Claudio; Foresti,Fausto.
In the present study, five callichthyid species belonging to the subfamily Corydoradinae were karyotyped: three species of Aspidoras and two of Corydoras. The three species of Aspidoras had the same diploid number, 2n = 46 chromosomes, similar karyotypic formulae, with most chromosomes metacentric or submetacentric, single interstitial Ag-NORs and C-band positive segments mainly found in the centromeric position. The comparative analysis of cytogenetic data available for the genus Aspidoras and other species of Corydoradinae suggest that several events of centric fusion occurred in the origin of the species of Aspidoras. The two analyzed species of Corydoras showed high diploid numbers, 2n = 74 in C. sodalis and 2n = 90 in C. britskii. While C. sodalis...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Fish cytogenetic; Karyotype; NOR; C-banding; Karyotypic evolution.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572004000400014

Mitochondrial DNA variation in wild populations of Leporinus elongatus from the Paraná River basin
Provedor de dados: Genetics and Molecular Biology
Autores: Martins,Cesar; Wasko,Adriane P.; Oliveira,Claudio; Foresti,Fausto.
Leporinus elongatus, a fish species widely distributed throughout the Paraná River basin in South America, is an important fishery resource and a valuable species in aquaculture programs. Despite its great economic importance, several wild populations have been suffering a drastic reduction. The comprehension of its population structure represents an important step for the conservation of these organisms in natural environments, and also for the selection of wild stocks to be used in hatchery programs. In order to understand the genetic-population structure of L. elongatus, D-loop mitochondrial DNA analyses were applied in six wild populations of the species. The results were used to estimate the levels of within and among population genetic variability....
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Conservation genetics; D-loop; Genetic variability; Leporinus elongatus; MtDNA.
Ano: 2003
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572003000100006

Analysis of the synaptonemal complex of the nine-banded armadillo, Dasypus novemcinctus
Provedor de dados: Genetics and Molecular Biology
Autores: Scavone,Márcia Denise da Paixão; Oliveira,Claudio; Bagagli,Eduardo; Foresti,Fausto.
The synaptonemal complex (SC) of three specimens of the nine-banded armadillo (Dasypus novemcinctus) was analyzed. Thirty-two bivalents (2n = 64) were observed, 31 of them being autosomes and one an XY sexual bivalent. Chromosome synapsis processes and nucleolus structure changes were analyzed in zygotene and pachytene cells, allowing a detailed description of the beginning of meiotic prophase in this species. There was complete synapsis of X and Y chromosomes. Some abnormalities in SC were observed in cells during zygotene and at the beginning of pachytene, but not in cells in the middle and late pachytene, suggesting the occurrence of synaptic adjustments in their SC.
Tipo: Info:eu-repo/semantics/other
Ano: 2000
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572000000300020

A brief history of fish genetics in Brazil
Provedor de dados: Genetics and Molecular Biology
Autores: Foresti,Fausto.
Tipo: Info:eu-repo/semantics/other
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572008000200038

Nucleotide sequence, genomic organization and chromosome localization of 5S rDNA in two species of Curimatidae (Teleostei, Characiformes)
Provedor de dados: Genetics and Molecular Biology
Autores: Santos,Lessandra Viviane de Rosa; Foresti,Fausto; Wasko,Adriane Pinto; Oliveira,Claudio; Martins,Cesar.
The 5S ribosomal DNA (5S rDNA) of higher eukaryotes is organized in repeat units of tandem arrays composed of a 5S rDNA coding region, conserved even among non-related taxa, and a variable non-transcribed spacer sequence (NTS). To contribute to knowledge on the organization and evolution of vertebrate 5S rDNA we used PCR, nucleotide sequencing, Southern blot hybridization and chromosome fluorescence in situ hybridization (FISH) to investigate 5S rDNA tandem repeats in the South American Curimatidae fish Steindachnerina insculpta and Cyphocharax modesta. 5S rDNA repeats of 180 base pairs (bp) from both species were PCR-generated and sequenced evidencing the shortest 5S rDNA monomer so far described in eukaryote species. Southern blotting revealed that both...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Cyphocharax modesta; Steindachnerina insculpta; 5S rDNA; Chromosomes; FISH; Nucleotide sequence.
Ano: 2006
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572006000200009

Cytogenetic analysis of three sea catfish species (Teleostei, Siluriformes, Ariidae) with the first report of Ag-NOR in this fish family
Provedor de dados: Genetics and Molecular Biology
Autores: Nirchio,Mauro; Martinez,Emanuel Ricardo Monteiro; Foresti,Fausto; Oliveira,Claudio.
Despite their ecological and economical importance, fishes of the family Ariidae are still genetically and cytogenetically poorly studied. Among the 133 known species of ariids, only eight have been karyotyped. Cytogenetic analyses performed on Genidens barbus and Sciades herzbergii revealed that both species have 2n = 56 chromosomes and Cathorops aff. mapale has 2n = 52 chromosomes: Genidens barbus has 10 Metacentrics (M), 14 Submetacentrics (SM), 26 Subtelocentrics (ST), and 6 Acrocentrics (A), Sciades herzbergii has 14M, 20SM, 18ST and 4A, whereas Cathorops aff. mapale has 14M, 20SM, and 18ST. The nucleolus organizer regions (NORs) were found in a single chromosome pair on the short arm of a large-sized ST pair in Genidens barbus and on the short arm of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Cytogenetics; Ag-NORs; Chromosome evolution; Chromosome rearrangements; Fish.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572010000200011

Description of a ZZ/ZW sex chromosome system in Thoracocharax cf. stellatus (Teleostei, Characiformes, Gasteropelecidae)
Provedor de dados: Genetics and Molecular Biology
Autores: Carvalho,Margarida Lima; Oliveira,Claudio; Foresti,Fausto.
The family Gasteropelecidae is composed of three genera and eight species. This study shows that Thoracocharax cf. stellatus has 2n = 52 chromosomes for both sexes. The five males studied showed 8 metacentric, 16 submetacentric, 4 subtelocentric, and 24 acrocentric chromosomes; the seven females showed only one submetacentric chromosome, belonging to pair 11, and one extra acrocentric chromosome, smaller than all the other chromosomes, characterizing the presence of a ZZ/ZW sex chromosome system in this species. Nucleolus organizing regions (NORs) were detected on the short arms of the subtelocentric chromosome pair 13. Constitutive heterochromatin was identified at pericentromeric and terminal positions in almost all chromosomes. The W chromosome was...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Sex chromosomes; ZW; DNA content; Fish; Evolution.
Ano: 2002
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572002000300008

Karyotypic conservatism in five species of Prochilodus (Characiformes, Prochilodontidae) disclosed by cytogenetic markers
Provedor de dados: Genetics and Molecular Biology
Autores: Voltolin,Tatiana Aparecida; Penitente,Manolo; Mendonça,Bruna Bueno; Senhorini,José Augusto; Foresti,Fausto; Porto-Foresti,Fábio.
The family Prochilodontidae is considered a group with well conserved chromosomes characterized by their number, morphology and banding patterns. Thence, our study aimed at accomplishing a cytogenetic analysis with conventional methods (Giemsa staining, silver staining of the nucleolus organizer regions-AgNOR, and C-banding) and fluorescence in situ hybridization (FISH) with 18S and 5S ribosomal DNA probes in five species of the Prochilodus genus (Prochilodus argenteus, Prochilodus brevis, Prochilodus costatus, Prochilodus lineatus and Prochilodus nigricans) collected from different Brazilian hydrographic basins. The results revealed conservatism in chromosome number, morphology, AgNORs 18S and 5S rDNAs location and constitutive heterochromatin...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: AgNOR; C-banding; Hydrographic basins; Conserved karyotype; FISH.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572013000300008

R- and G-band patterns in Astyanax scabripinnis paranae (Pisces, Characiformes, Characidae)
Provedor de dados: Genetics and Molecular Biology
Autores: Maistro,Edson Luis; Foresti,Fausto; Oliveira,Claudio.
The absence of longitudinal bands in fish chromosomes has been associated with technical problems in chromosome preparations or the absence of a structural compartmentalization in the fish genome. In the present study, a R-banding pattern was obtained using a replication banding technique by in vivo treatment with 5-bromodeoxyuridine (5-BrdU). G-banding patterns were obtained after trypsin treatment and also after chromosome cleavage by in situ treatment with the restriction endonuclease BamHI. A similar G-banding pattern was also obtained after cleavage with the endonuclease HinfI. Presence of a resolute R- and G-banding patterns shows that Astyanax scabripinnis paranae chromosomes could present an isochore-like structure similar to that found in other...
Tipo: Info:eu-repo/semantics/article
Ano: 1999
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47571999000200011

Cytogenetic characterization of the strongly electric Amazonian eel, Electrophorus electricus (Teleostei, Gymnotiformes), from the Brazilian rivers Amazon and Araguaia
Provedor de dados: Genetics and Molecular Biology
Autores: Fonteles,Soraia B.A.; Lopes,Carlos E.; Akama,Alberto; Fernandes,Flora M.C.; Porto-Foresti,Fábio; Senhorini,José A.; Daniel-Silva,Maria de Fátima Z.; Foresti,Fausto; Almeida-Toledo,Lurdes Foresti de.
A karyotype analysis of the electric eel, Electrophorus electricus (Teleostei, Gymnotiformes), a strongly electric fish from northern South America, is presented. Two female specimens were analyzed, one from the Amazon River and one from the Araguaia River. The specimens had a chromosomal number of 2n = 52 (42M-SM + 10A). C-bands were present in a centromeric and pericentromeric position on part of the chromosomes; some interstitial C-bands were also present. Heteromorphic nucleolus organizer regions (NORs) were detected in two chromosome pairs of the specimen from the Amazon River. The chromosome number and karyotype characteristics are similar to those of other Gymnotidae species. The genera Electrophorus and Gymnotus are positioned as the basal lineages...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Chromosome; Fish; Gymnotidae; Electric eel.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572008000200010

Genetic variability of two populations of Pseudoplatystoma reticulatum from the Upper Paraguay River Basin
Provedor de dados: Genetics and Molecular Biology
Autores: Abreu,Marcia Matos de; Pereira,Luiz Henrique Garcia; Vila,Vilma Barretto; Foresti,Fausto; Oliveira,Claudio.
Catfishes of the genus Pseudoplatystoma are very important species due to both their high commercial value and their ecological role as voracious predators. They undertake lengthy migratory movements during their life-cycle, this including reproductive migration which occurs from October to December in the rainy season. In the present study, seven microsatellite loci were analyzed to access genetic variability in two samples of P. reticulatum from the Upper Paraguay Basin. The loci were highly polymorphic (mean = 7.28). According to all analysis, the two samples of P. reticulatum revealed pronounced genetic differentiation. Fst value was 0.2290, Rst value 0.1067 and AMOVA 22.90% (Fst) and 10.67% (Rst), all being highly significant (p &lt; 0.001). The...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Fish; Population genetics; Microsatellite; Homing; Population structure.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572009000400032

Sympatric occurrence of two cytotypes of Astyanax scabripinnis (Characiformes, Characidae)
Provedor de dados: Genetics and Molecular Biology
Autores: Maistro,Edson Luis; Oliveira,Claudio; Foresti,Fausto.
Among four specimens of Astyanax scabripinnis sympatrically collected from the Tamanduá stream (State of São Paulo, Brazil), three, named cytotype I, had 2n = 50 chromosomes (6M + 26SM + 4ST + 14A) and a fundamental number (FN) of 86, and one specimen, named cytotype II, had 2n = 48 chromosomes (6M + 28SM + 4ST + 10A) and FN = 86. Besides the difference in diploid number, the cytotypes showed a clear difference in the distribution of constitutive heterochromatin. One NOR-bearing chromosome pair was detected in both cytotypes and one specimen of cytotype I had multiple NORs (tree chromosome pairs). Robertsonian translocations and an increase or loss of heterochromatin are proposed to explain the karyotypic divergence observed. Some aspects related to the...
Tipo: Info:eu-repo/semantics/other
Ano: 2000
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572000000200021

5S rDNA characterization in twelve Sciaenidae fish species (Teleostei, Perciformes): depicting gene diversity and molecular markers
Provedor de dados: Genetics and Molecular Biology
Autores: Alves-Costa,Fernanda A.; Martins,Cesar; Matos,Fernanda Del Campos de; Foresti,Fausto; Oliveira,Claudio; Wasko,Adriane P.
In order to extend the genetic data on the Sciaenidae fish family, the present study had the purpose to characterize PCR-generated 5S rDNA repeats of twelve species of this group through PAGE (Polyacrylamide Gel Electrophoresis) analysis. The results showed the occurrence of at least two different 5S rDNA size classes in all the species. Moreover, 5S rDNA repeats of one of the studied species - Isopisthus parvipinnis - were cloned and subjected to nucleotide sequencing and Southern blot membrane hybridization analyses, which permitted to confirm the existence of two major 5S rDNA classes. Phylogenetic analysis based on the nucleotide sequences of different 5S rDNA repeats of I. parvipinnis lead to their separation into two major clusters. These results may...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Sciaenidae; Fish; Isopisthus parvipinnis; 5S rDNA; Molecular markers.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572008000200025

Analysis of NOR distribution in cultivated and naturalized stocks of rainbow trout (Oncorhynchus mykiss)
Provedor de dados: Genetics and Molecular Biology
Autores: Porto-Foresti,Fábio; Oliveira,Claudio; Tabata,Yara A.; Rigolino,Marcos G.; Foresti,Fausto.
In salmonid species, nucleolar organizing regions (NORs) have frequently been found on a single chromosome pair. However, some other, smaller yet active NORs have also been described. In the present study, NORs were found to be located in different positions on the chromosomes of 12 rainbow trout samples (11 cultivated and one naturalized stocks). Three phenotypes were found: 1) NORs located on two submetacentric chromosomes, in a subterminal position on the short arm (AA); 2) NORs located on two submetacentric chromosomes, in a subterminal position on the long arm (BB); and 3) NORs located on two submetacentric chromosomes, one in a subterminal position on the short arm, and the other in a subterminal position on the long arm (AB). Phenotype AA was...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: NOR polymorphism; Fish cytogenetics; Rainbow trout.
Ano: 2002
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572002000400009

Nuclear DNA content determination in Characiformes fish (Teleostei, Ostariophysi) from the Neotropical region
Provedor de dados: Genetics and Molecular Biology
Autores: Carvalho,Margarida Lima; Oliveira,Claudio; Navarrete,Maria Clara; Froehlich,Otávio; Foresti,Fausto.
In the present study, nuclear DNA content was analyzed in 53 species of Characiformes fish from the Neotropical region. Diploid number ranged from 2n = 48 in Astyanax fasciatus, Gymnocorymbus ternetzi and Hyphessobrycon griemi to 2n = 102 in Potamorhina squamoralevis, with a modal number of 54 chromosomes. Nuclear DNA content ranged from 1.70 ± 0.04 pg of DNA per diploid nucleus in Acestrorhynchus pantaneiro to 3.94 ± 0.09 pg in Tetragonopterus chalceus. A general analysis showed a mean value of 2.9 pg of DNA per diploid nucleus. Very similar DNA content values were observed in the species of the family Cynodontidae which showed a variation of 3% between the two genera studied. Small variations were observed between populations of Gymnocorymbus ternetzi,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Nuclear DNA; DNA content; Chromosome; Fish; Evolution.
Ano: 2002
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572002000100010

Cytogenetic analysis of three catfish species of the family Pseudopimelodidae (Teleostei, Siluriformes)
Provedor de dados: Genetics and Molecular Biology
Autores: Martinez,Emanuel Ricardo Monteiro; Nirchio,Mauro; Granado,Angel; Foresti,Fausto; Oliveira,Claudio.
Cytogenetic analyses performed in Cephalosilurus apurensis, Microglanis aff. cottoides and Pseudopimelodus bufonius revealed that the three species have 2n = 54 chromosomes: C. apurensis presented six metacentric (M), 28 submetacentric (SM), 14 subtelolocentric (ST), and six acrocentric (A) chromosomes, while M. aff. cottoides showed 10M, 32SM, 10ST and 2A, and P. bufonius had 12M, 30SM and 12ST. The nucleolus organizer regions (NORs) were present on the short arm of a middle-sized ST pair, identified as pair 19, in C. apurensis NORs were found on the short arm of a middle-sized ST (pair 23) and on the long arm of a middle-sized ST (pair 22) in M. aff. cotttoides and on the short arm of three middle-sized ST pairs, identified as pairs 9, 10 and 11, in P....
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Karyotype; Chromosomes; C-banding; Ag-NOR; Fish.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572008000400015

Karyotypic conservatism in samples of Characidium cf. zebra (Teleostei, Characiformes, Crenuchidae): physical mapping of ribosomal genes and natural triploidy
Provedor de dados: Genetics and Molecular Biology
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

Supernumerary chromosomes in the pufferfish Sphoeroides spengleri: first occurrence in marine Teleostean Tetraodontiformes fish
Provedor de dados: Genetics and Molecular Biology
Autores: Alves,Anderson Luis; Porto-Foresti,Fábio; Oliveira,Claudio; Foresti,Fausto.
Cytogenetic analyses carried out in eight specimens of Sphoeroides spengleri revealed the presence of 2n = 46 chromosomes (20 M/SM and 26 ST/A). Besides the standard karyotypical set, the presence of B microchromosomes was observed in two individuals, ranging from 0 to 2 microchromosomes per cell. A karyotype composed by 2n = 46 chromosomes with occurrence of M and SM chromosomes is considered basal for the species from the clade comprising the families Tetraodontidae, Balistidae, and Diodontidae, although it represents a derived condition for the order Tetraodontiformes, whose basal karyotype would be composed by 2n = 48 acrocentric chromosomes. The occurrence of B microchromosomes in marine Tetraodontiformes fish was not known, and this represents the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: B chromosome; Pufferfish; Sphoeroides spengleri.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572008000200014

Nuclear DNA content in 20 species of Siluriformes (Teleostei: Ostariophysi) from the Neotropical region
Provedor de dados: Genetics and Molecular Biology
Autores: Fenerich,Paulo César; Foresti,Fausto; Oliveira,Claudio.
In the present study, 20 species of Siluriformes fish were analyzed in order to determine their nuclear DNA content and compare these data with their diploid number. In addition, the extension and importance of the changes that occurred during the process of diversification in the group of Neotropical freshwater catfish were investigated. The only species studied of the family Doradidae, Rhinodoras d'orbignyi (2n = 58), presented 3.46 ± 0.13 pg of DNA. Among the species of the family Heptapteridae, the values of nuclear DNA content and the diploid numbers ranged from 1.13 ± 0.09 pg of DNA in Pimelodella sp. (2n = 46) to 2.38 ± 0.07 pg of DNA in Imparfinis mirini (2n = 58). The family Loricariidae showed the widest variation in diploid number and nuclear...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Nuclear DNA; DNA content; Chromosome; Fish; Evolution.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572004000300008

Scattered organization of the histone multigene family and transposable elements in Synbranchus
Provedor de dados: Genetics and Molecular Biology
Autores: Utsunomia,Ricardo; Pansonato-Alves,José Carlos; Scacchetti,Priscilla Cardim; Oliveira,Claudio; Foresti,Fausto.
The fish species Synbranchus marmoratus is widely distributed throughout the Neotropical region and exhibits a significant karyotype differentiation. However, data concerning the organization and location of the repetitive DNA sequences in the genomes of these karyomorphs are still lacking. In this study we made a physical mapping of the H3 and H4 histone multigene family and the transposable elements Rex1 and Rex3 in the genome of three known S. marmoratus karyomorphs. The results indicated that both histone sequences seem to be linked with one another and are scattered all over the chromosomes of the complement, with a little compartmentalization in one acrocentric pair, which is different from observations in other fish groups. Likewise, the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Synbranchidae; FISH; Histone; Retrotransposon.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572014000100007

A lethal effect associated with polymorphism of the NOR-bearing chromosomes in rainbow trout (Oncorhynchus mykiss)
Provedor de dados: Genetics and Molecular Biology
Autores: Porto-Foresti,Fábio; Oliveira,Claudio; Gomes,Eduardo A.; Tabata,Yara A.; Rigolino,Marcos G.; Foresti,Fausto.
Cytogenetic analysis of a rainbow trout stock showed that the nucleolar organizing regions were located subterminally on the long arm of a submetacentric chromosome pair and occurred as a single chromosomal segment (phenotype N1) or as two chromosomal segments separated by a short euchromatic segment (phenotype N2). Cytogenetic analysis also showed that there were N1N1 and N1N2 individuals but no N2N2 individuals. Analysis of the different includedphenotypes incluted that the population was not in Hardy-Weinberg equilibrium (chi² = 19.333; p &lt; 0.01), and that a higher frequency of individuals had the N1N2 phenotype. Experimental crosses involving four males (two N1N1 and two N1N2) and four females (one N1N1 and three N1N2) yielded eight broods. There...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: NOR polymorphism; Paracentric inversion; Fish cytogenetics; Rainbow trout.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572004000100009

Nuclear DNA content of thirty species of Neotropical fishes
Provedor de dados: Genetics and Molecular Biology
Autores: Carvalho,Margarida Lima; Oliveira,Claudio; Foresti,Fausto.
The present paper reports nuclear DNA content in 30 Neotropical freshwater fish species and summarizes the data on other Neotropical species presented in the literature. Among Neotropical fishes, the nuclear DNA content ranges from 1.04 ± 0.09 pg/nucleus in Corydoras cf. simulatus (2n = 62) to 248.0 pg/nucleus in Lepidosiren paradoxa (2n = 38). A general analysis of the data obtained in the present study for each species showed that DNA measurements were practically constant at the individual level, while significant differences were observed among individuals of the same population. This observation was valid for all species analyzed and was more evident in those species that presented other karyotypic particularities such as sex chromosomes or...
Tipo: Info:eu-repo/semantics/article
Ano: 1998
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47571998000100009

Comparative cytogenetic and morphological analysis of Astyanax scabripinnis paranae (Pisces, Characidae, Tetragonopterinae)
Provedor de dados: Genetics and Molecular Biology
Autores: Maistro,Edson Luis; Oliveira,Claudio; Foresti,Fausto.
Cytogenetic and morphological studies were carried out on nine local populations of Astyanax scabripinnis paranae. All populations exhibited 2n = 50 chromosomes as well as conspicuous differences involving karyotype morphology, number and position of nucleolar organizer regions (NORs) and amount and/or locations of constitutive heterochromatin blocks. A quantitative study of the cytogenetic data showed that eight populations possessed different karyotypes. Morphological analyses based on nine measurements and two meristic parameters were effective in establishing clear identification of five populations. Comparative analysis of cytogenetic and morphological traits suggests that chromosomal changes have occurred at a more rapid rate than morphological...
Tipo: Info:eu-repo/semantics/article
Ano: 1998
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47571998000200005

Karyological characterization of four Neotropical fish species of the genus Hisonotus (Teleostei, Loricariidae, Hypoptopomatinae) from distinct Brazilian river basins
Provedor de dados: Genetics and Molecular Biology
Autores: Andreata,Artur Antonio; Oliveira,Claudio; Foresti,Fausto.
The karyotypes of four Hisonotus species (two provisionally-named species A and D, H. nigricauda, and H. leucofrenatus) were found to have the same diploid number of 2n = 54 and interstitial silver-staining nucleolus organizer regions (Ag-NORs) located on the long arm of the largest metacentric pair. The C-banding pattern appeared to be species-specific, with one group (H. nigricauda and the unnamed species A and D) being characterized by small amounts of positive C-banded segments and containing a sub-group (species A and D) identified by a large positive C-banded segment on a small metacentric chromosome pair. The second group contained different samples of H. leucofrenatus, characterized by a larger amount of C-band positive segments spread over several...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Fish cytogenetics; Karyotypes; Ag-NORs; C-band; Chromosome evolution.
Ano: 2006
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572006000100013

Identification and description of distinct B chromosomes in Cyphocharax modestus (Characiformes, Curimatidae)
Provedor de dados: Genetics and Molecular Biology
Autores: Santos,Lessandra Viviane De Rosa; Foresti,Fausto; Martins,Cesar; Oliveira,Claudio; Wasko,Adriane Pinto.
Cytogenetic analyses were performed in Cyphocharax modestus, collected at Paranapanema River and Tietê River (São Paulo State, Brazil). A karyotype with 2n = 54 chromosomes was observed in the animals from both Brazilian freshwater river systems. One to four B chromosomes were also detected in individuals from the Paranapanema River, which represents the probable first report of more than a single supernumerary element in a species of the Curimatidae group. C-banding revealed centromeric and telomeric heterochromatin blocks in several chromosomes of the normal karyotype complement of C. modestus. Moreover, while some B chromosomes were characterized by the complete absence of C-bands, others were totally heterochromatic. Although there was a prevalence of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: B chromosomes; C-banding; Curimatidae; Cyphocharax modestus; Supernumerary chromosomes.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572008000200019

Karyotype description of five species of Trichomycterus (Teleostei: Siluriformes: Trichomycteridae)
Provedor de dados: Genetics and Molecular Biology
Autores: Sato,Luciana Ramos; Oliveira,Claudio; Foresti,Fausto.
Trichomycteridae is a family of small catfish which are widely distributed throughout Southern Central America and South America. The present study showed that the cis-Andean species Trichomycterus florensis, Trichomycterus sp. aff. Trichomycterus itatiyae, Trichomycterus reinhardti, Trichomycterus davisi and Trichomycterus auroguttatus had 2n = 54 chromosomes (42 metacentric, 10 submetacentric and 2 subtelocentric), with T. reinhardti, T. auroguttatus and T. sp. aff. T. itatiyae exhibiting only one chromosome pair with silver-stained nucleolus organizer regions (NORs). The cytogenetic data suggest the existence of at least two groups of species in the cis-Andean representatives of the genus Trichomycterus. In the first group the first metacentric pair is...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Chromosome evolution; NOR banding; Fish.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572004000100008

Editorial
Provedor de dados: Genetics and Molecular Biology
Autores: Foresti,Fausto; Galetti Junior,Pedro Manoel.
Tipo: Info:eu-repo/semantics/other
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572008000200001

Identities among actin-encoding cDNAs of the Nile tilapia (Oreochromis niloticus) and other eukaryote species revealed by nucleotide and amino acid sequence analyses
Provedor de dados: Genetics and Molecular Biology
Autores: Poletto,Andréia B.; Wasko,Adriane P.; Oliveira,Claudio; Azevedo,Alexandre; Carvalho,Robson F.; Silva,Maeli Dal Pai; Foresti,Fausto; Martins,Cesar.
Actin-encoding cDNAs of Nile tilapia (Oreochromis niloticus) were isolated by RT-PCR using total RNA samples of different tissues and further characterized by nucleotide sequencing and in silico amino acid (aa) sequence analysis. Comparisons among the actin gene sequences of O. niloticus and those of other species evidenced that the isolated genes present a high similarity to other fish and other vertebrate actin genes. The highest nucleotide resemblance was observed between O. niloticus and O. mossambicus a-actin and b-actin genes. Analysis of the predicted aa sequences revealed two distinct types of cytoplasmic actins, one cardiac muscle actin type and one skeletal muscle actin type that were expressed in different tissues of Nile tilapia. The...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Actin; Expression pattern; Nile tilapia; Oreochromis niloticus.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572008000200031

Cytogenetic analysis of five Hypostomus species (Siluriformes, Loricariidae)
Provedor de dados: Genetics and Molecular Biology
Autores: Martinez,Emanuel Ricardo Monteiro; Zawadzki,Claudio Henrique; Foresti,Fausto; Oliveira,Claudio.
In this work, we analyzed the karyotypes of five species. Hypostomus cf. heraldoi, from the Mogi-Guaçu River, had 2n = 72 chromosomes, with a nucleolar organizer region (NOR) in one chromosomal pair. Hypostomus regani, from the Mogi-Guaçu River had 2n = 72 chromosomes with NORs in two chromosomal pairs. Hypostomus sp., from the Mogi-Guaçu River basin, had 2n = 68 chromosomes, with NORs in two chromosomal pairs. Hypostomus aff. agna, from Cavalo Stream, had 2n = 74 chromosomes with NORs in two chromosomal pairs. Hypostomus cf. topavae, from Carrapato Stream, had 2n = 80 chromosomes, with NORs in two chromosomal pairs. Hypostomus species showed marked diversity in the karyotypic formula, which suggested the occurrence of several Robertsonian rearrangements...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Chromosomes; Evolution; Hypostominae; Neotropical fish; NOR.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572011000400006

Intraspecific crosses resulting in the first occurrence of eight and nine B chromosomes in Prochilodus lineatus (Characiformes, Prochilodontidae)
Provedor de dados: Genetics and Molecular Biology
Autores: Voltolin,Tatiana Aparecida; Senhorini,José Augusto; Foresti,Fausto; Bortolozzi,Jehud; Porto-Foresti,Fábio.
B chromosomes are supernumerary elements present in about 15% of eukaryotic species and are most frequently heterochromatic, behave parasitically, show a transmission rate higher than standard (A) chromosomes, and can provoke harmful effects on carriers. In the current work, Prochilodus lineatus individuals carrying eight and nine B chromosomes were obtained by induced crossing performed involving breeders with different B chromosome numbers in their cells. The high B chromosome numbers found in the offspring were recorded for the first time in this species. The use of cytogenetic techniques applied in the present study revealed that regardless of the increase in number of B chromosomes in the genome of these individuals, those elements did not presented...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Supernumerary chromosome; Heterochromatic chromosome; Cross-fertilization.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572011000200009

Molecular and morphological approaches for species delimitation and hybridization investigations of two Cichla species
Provedor de dados: Iheringia Série Zoologia
Autores: Mourão,Andrea A. F.; Freitas-Souza,Diogo; Hashimoto,Diogo T.; Ferreira,Daniela C.; Prado,Fernanda D. do; Silveira,Rosicleire V.; Foresti,Fausto; Porto-Foresti,Fábio.
ABSTRACT The hybridization is a widely-discussed issue in several studies with fish species. For some authors, hybridization may be related with diversification and speciation of several groups, or also with the extinction of populations or species. Difficulties to differentiate species and hybrids may be a problem to correctly apply a management of wild species, because hybrid lineages, especially the advanced ones, may resemble the parental species. The genus Cichla Bloch &amp; Schneider, 1801 constitutes an interesting experimental model, considering that hybridization and taxonomic uncertainties hinder a correct identification. Considering these problems, in this study, we developed genetic methodologies and applied meristic and morphometric approaches...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Cichla kelberi; Cichla piquiti; Carijó; Cluster Similarity; PCA; PCR-multiplex.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0073-47212017000100216

Chromosome evolution in fishes: a new challenging proposal from Neotropical species
Provedor de dados: Neotropical Ichthyology
Autores: Nirchio,Mauro; Rossi,Anna Rita; Foresti,Fausto; Oliveira,Claudio.
We present a database containing cytogenetic data of Neotropical actinopterygian fishes from Venezuela obtained in a single laboratory for the first time. The results of this study include 103 species belonging to 74 genera assigned to 45 families and 17 out of the 40 teleost orders. In the group of marine fishes, the modal diploid number was 2n=48 represented in 60% of the studied species, while in the freshwater fish group the modal diploid complement was 2n=54, represented in 21.21 % of the studied species. The average number of chromosomes and the mean FN were statistically higher in freshwater fish than in marine fish. The degree of diversification and karyotype variation was also higher in freshwater fish in contrast to a more conserved cytogenetic...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Actinopterygii; Ancestral karyotype; Diploid number; Fundamental number.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252014000400761

Molecular identification of intergenus crosses involving catfish hybrids: risks for aquaculture production
Provedor de dados: Neotropical Ichthyology
Autores: Hashimoto,Diogo T.; Prado,Fernanda D.; Foresti,Fausto; Porto-Foresti,Fábio.
ABSTRACT Monitoring of the interspecific hybrid production and trade is essential for the appropriate management of these animals in fish farms. The identification of catfish hybrids by morphological analysis is unreliable, particularly of juveniles and post-F1 individuals. Therefore, in the present study, we used five molecular markers (four nuclear genes and one mitochondrial gene) to detect hybrids in the trade of pimelodid juvenile fish from different stocks purchased of five seed producers in Brazil. Samples commercialized as pintado (pure species Pseudoplatystoma corruscans ) from three fish farms were genetically identified as hybrid cachapinta (♀ P. reticulatum x ♂ P. corruscans ). In the stocks purchased as cachandiá (hybrid between ♀ P....
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Fish farm; Hybridization; Molecular markers; Nuclear genes; Pimelodidae.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252016000200213

Populations analysis of the Brazilian Sharpnose Shark Rhizoprionodon lalandii (Chondrichthyes: Carcharhinidae) on the São Paulo coast, Southern Brazil: inferences from mt DNA sequences
Provedor de dados: Neotropical Ichthyology
Autores: Mendonça,Fernando Fernandes; Oliveira,Claudio; Gadig,Otto Bismarck Fazzano; Foresti,Fausto.
Sharks of the genus Rhizoprionodon can be considered some of the most important predators along the trophic coastal marine ecosystems and represent an important economic resource for the small-scale fisheries, especially on the Brazilian coastline. In order to analyze the population structure of the shark Rhizoprionodon lalandii of São Paulo, Southeastern coast of Brazil, levels of genetic diversity were identified by nucleotide sequence analyses of the mitochondrial DNA control region. The results obtained from this study present moderate values of haplotype diversity and low nucleotide diversity. Although the AMOVA tests (ΦST = 0.08394, P &lt; 0.01) had shown slightly differences among the studied samples, evidence for the occurrence of population...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: D-loop; Haplotypes; Mitochondrial control region; Shark conservation.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252009000200012

Cytogenetic and molecular markers reveal the complexity of the genus Piabina Reinhardt, 1867 (Characiformes: Characidae)
Provedor de dados: Neotropical Ichthyology
Autores: Pazian,Marlon Felix; Pereira,Luiz Henrique Garcia; Shimabukuru-Dias,Cristiane Kioko; Oliveira,Claudio; Foresti,Fausto.
Cytogenetic and molecular analyses were carried out in fish representative of the genus Piabina. This study specifically involved the species P. argentea and P. anhembi collected from areas of the Paranapanema and Tietê River basins, Brazil. Our findings suggest that fish classified as Piabina argentea in the Paranapanema and Tietê Rivers may represent more than one species. The samples analyzed differed by cytogenetic particularities and molecular analyses using partial sequences of the genes COI and CytB as genetic markers revealed three distinct groups of P. argentea with genetic distances sufficient to support the conclusion that the three samples analyzed are three distinct taxonomic units.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: DNA Barcoding; Freshwater fishes; Fish; MtDNA; 18S rDNA; 5S rDNA.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252012000200008

Molecular and cytogenetic analyses of cryptic species within the Synbranchus marmoratus Bloch, 1795 (Synbranchiformes: Synbranchidae) grouping: species delimitations, karyotypic evolution and intraspecific diversification
Provedor de dados: Neotropical Ichthyology
Autores: Utsunomia,Ricardo; Pansonato-Alves,José C.; Costa-Silva,Guilherme J.; Mendonça,Fernando F.; Scacchetti,Priscilla C.; Oliveira,Claudio; Foresti,Fausto.
The fish species Synbranchus marmoratushas been reported to exist as a species complex due to high intraspecific karyotypic variability in spite of the difficulty or impossibility to distinguish them using morphological traits alone. The goal of this work was to use cytogenetic and molecular methods to determine the species delimitations and understand the karyoevolution ofS. marmoratususing samples collected from distinct Brazilian localities. Among the analyzed specimens, a large degree of cytogenetic variation related to diploid numbers and karyotype structure was observed, with karyotypes showing 2n=42, 44 and 46 chromosomes. In addition, using sequences of three mitochondrial genes, the phylogenetic relationships between every sample with a known...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Chromosomal diversity; Fish cytogenetics; Karyotype evolution; Repetitive DNA; Species complex.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252014000400903

Surprising genomic diversity in the Neotropical fish Synbranchus marmoratus (Teleostei: Synbranchidae): how many species?
Provedor de dados: Neotropical Ichthyology
Autores: Torres,Rodrigo Augusto; Roper,James Joseph; Foresti,Fausto; Oliveira,Claudio.
Chromosomes and nuclear DNA content variation in the eel Synbranchus marmoratus were studied in seven samples taken from rio Paraguay and rio Paraná basins to examine whether karyotype and nuclear DNA content variations could offer useful information for the characterization of independent evolutionary lineages in the genus and construction of evolutionary and biogeographical hypotheses. The occurrence of different karyotypes was already described for this species; however, a new cytotype from rio Miranda was discovered. Nuclear DNA content showed a wide variation among samples and individuals, ranging from 5.2 to 9.1 pg of DNA/nuclei. An analysis of variance confirmed the occurrence of significant differences among samples. In a deeper series of analyses,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Fish DNA; Chromosomes; Genome diversity; Karyotype; Synbranchus marmoratus.
Ano: 2005
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252005000200005

Interspecific chromosomal divergences in the genus Characidium (Teleostei: Characiformes: Crenuchidae)
Provedor de dados: Neotropical Ichthyology
Autores: Alves,José Carlos Pansonato; Paiva,Luiz Ricardo de Souza; Oliveira,Claudio; Foresti,Fausto.
Karyotypes of seven fish species of the genus Characidium, three of them studied for the first time, were characterized using conventional cytogenetic techniques (Giemsa staining, Ag-NOR, and C-banding). All species presented a diploid number of 2n=50, with only metacentric and submetacentric chromosomes, as observed in all Characidium species studied. In two species cells with one to three B chromosomes were observed. All species analyzed have a single NOR-bearing chromosome pair with morphological differences among them. Characidium cf. zebra shows heterochromatic blocks restricted to the pericentromeric regions of all chromosomes denoting the absence of a sex chromosome system. On the other hand, the species Characidium lanei, C. pterostictum, C....
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Karyotypic evolution; Sex chromosomes; B-chromosomes; Ag-NORs.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252010000100010

Cytotaxonomic diagnosis of Trichomycterus diabolus (Teleostei: Trichomycteridae) with comments about its evolutionary relationships with co-generic species
Provedor de dados: Neotropical Ichthyology
Autores: Torres,Rodrigo A.; Oliveira,Claudio; Foresti,Fausto.
The karyotype and the Ag-NOR location of a sample of Trichomycterus diabolus collected in the córrego Hortelã (Botucatu, São Paulo, Brazil) are described. The species exhibited 2n=56 chromosomes (42 metacentrics, 12 submetacentrics and 2 subtelocentrics) and the nucleolus organizing region located near to the centromere on the long arm of the largest metacentric pair. The presence of 2n=56 chromosomes in T. diabolus is an interesting characteristic since until now all cis-Andean species karyotyped presented 2n=54 chromosomes while almost all trans-Andean species presented different diploid numbers. The possible origin of this unexpected karyotypic form is discussed.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Trichomycterinae; Karyotype; Chromosome evolution; Fish cytogenetic.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252004000300003

The roles of marginal lagoons in the maintenance of genetic diversity in the Brazilian migratory fishes Prochilodus argenteus and P. costatus
Provedor de dados: Neotropical Ichthyology
Autores: Melo,Bruno F.; Sato,Yoshimi; Foresti,Fausto; Oliveira,Claudio.
The rio São Francisco basin contains many endemic species, such as Prochilodus argenteus and P. costatus, which have great commercial importance. However, information about the main recruitment sites and genetic studies containing extensive sampling of these species are scarce. To investigate the roles of the marginal lagoons in the maintenance of genetic variability and in the population structure, we analyzed six microsatellite loci in nine sampling groups of P. argenteusand five sampling groups of P. costatus. Our results showed high levels of genetic variability and low values of genetic differentiation for P. argenteus (FST =0.008, P&lt; 0.05) and for P. costatus(FST =0.031, P &lt; 0.05). In addition, high values of gene flow combined with a small...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Conservation genetics; Fish migration; Microsatellite; Nursery area; Rio São Francisco basin.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252013000300625

Karyotype description and evidence of multiple sex chromosome system X1X1X2X2/X1X2Y in Potamotrygon aff. motoro and P. falkneri (Chondrichthyes: Potamotrygonidae) in the upper Paraná River basin, Brazil
Provedor de dados: Neotropical Ichthyology
Autores: Cruz,Vanessa Paes da; Shimabukuro-Dias,Cristiane Kioko; Oliveira,Claudio; Foresti,Fausto.
Cytogenetic analysis of Potamotrygon aff. motoro and P. falkneri indicated the occurrence of an X1X1X2X2/X1X2 Y multiple sex chromosome system in both species, with 2n = 66 chromosomes for females and 2n = 65 chromosomes for males. The nucleolus organizer regions (NORs) identified using Ag-NOR technique showed that both species have multiple Ag-NORs (5 to 7 chromosomes stained). C-banding technique indicated the presence of heterochromatic blocks in the centromeric regions of almost all chromosomes in both species. Through this study there was evidence of heterogeneity in the karyotypes, which suggests that chromosomal rearrangements such as inversions and/or translocations occurred during the chromosomal evolution in two species of this genus.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Cytogenetic; NOR; C-band; Fish; Stingrays.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252011000100020

Microstructural chromosome reorganization in the genus Trichomycterus (Siluriformes: Trichomycteridae)
Provedor de dados: Neotropical Ichthyology
Autores: Oliveira,Maria Lígia M. de; Utsunomia,Ricardo; Pansonato-Alves,José Carlos; Scacchetti,Priscilla C.; Primo,Cleberson C.; Vicari,Marcelo R.; Artoni,Roberto F.; Centofante,Liano; Moreira-Filho,Orlando; Oliveira,Claudio; Foresti,Fausto.
Trichomycterus is a specious fish genus within Trichomycterinae and displays remarkable karyotype diversity. However, knowledge about their genomic structure and location of repetitive sequence is still limited. In order to better understand the karyotype diversification, we analyzed nine species of Trichomycterus using classical and molecular cytogenetic techniques. Results revealed a conserved diploid chromosome number of 2n=54 chromosomes in all analyzed species, although remarkable differences on the constitutive heterochromatin distribution were observed. In addition, while the 18S rDNA showed a conserved distribution pattern, the 5S rDNA sites showed a quite diverse location considering the analyzed species. Remarkably, both ribosomal genes were...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Karyotype diversity; Repetitive DNA; RDNA; Supernumerary chromosomes.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252016000200211

A comparative structural cytogenetic study in three allopatric populations of Astyanax scabripinnis (Teleostei: Characidae)
Provedor de dados: Revista Brasileira de Zoologia
Autores: Santos,Natália M.; Ferreira-Neto,Maressa; Artoni,Roberto F.; Vicari,Marcelo R.; Bakkali,Mohammed; Oliveira,Claudio de; Foresti,Fausto.
Individual samples from five populations of the characid fish Astyanax scabripinnis (Jenyns, 1842) from the Tietê and Paranapanema river basins (Brazil) were studied. All individuals analyzed presented 50 chromosomes but three different karyotypic forms were observed. Additionally, some individuals of one karyomorph presented a macro supernumerary chromosome. No chromosomal differentiation was observed between males and females in any sample analyzed. C-banding revealed two distinct distribution patterns in these populations in which strong terminally located heterochromatic blocks were detected in the long arms of some chromosomes of the specimens from Cascatinha, Cintra, and Funari streams, whereas populations of the Capão Bonito stream and the Barbosa...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Chromosome markers; Karyoevolution; Karyomorphs; Nucleolus organizer region.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-46702012000200008

Biologia populacional de Astyanax altiparanae Garutti &amp;amp; Britski (Teleostei, Characidae) do médio Rio Paranapanema, Paraná, Brasil
Provedor de dados: Zoologia
Autores: Orsi,Mário Luís; Carvalho,Edmir Daniel; Foresti,Fausto.
O objetivo desse trabalho foi a determinação da estrutura populacional da espécie. Foram escolhidos quatro locais de amostragem com características ambientais distintas na bacia do rio Tibagi. As amostragens foram realizadas mensalmente no período de janeiro de 1997 a fevereiro de 1998. Um total de 1553 indivíduos foram capturados, apresentando constância em todos os trechos, com as maiores abundâncias nos trechos do rio Congonhas (76 %). Variações ocorreram entre os trechos por fase de desenvolvimento e classes de comprimento e na distribuição espacial, demonstrando que a espécie apresenta estrutura populacional diferenciada. A espécie apresentou grande capacidade adaptativa exploratória, utilizando estratégias diferenciadas na estrutura da população. A...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Ecologia; Peixes; Tibagi.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81752004000200008

Seminal analysis, cryogenic preservation, and fertility in matrinxã fish, Brycon cephalus (Günther, 1869)
Provedor de dados: Brazilian Archives of Biology and Technology
Autores: Ninhaus-Silveira,Alexandre; Foresti,Fausto; Veríssimo-Silveira,Rosicleire; Senhorini,José Augusto.
Aiming to improve fish reproduction techniques, the characterization and cryopreservation of semen of Brycon cephalus were performed. The seminal characteristics observed were: an almost transparent, milky semen with a mean volume of 4mL, and sperm concentration of 9.617±1.630 x 10(6) spermatozoa/mm³. Spermatozoa (length = 31.288 ±4.47µm) were of the aquasperm type and displayed a small, round head (length = 1.727 ±0.18 µm; width = 1.752 ±0.17µm) without acrosomal vesicle, nucleus with highly condensed chromatin forming coarse clots and centriolar complex located in the nuclear fossa; a midpiece (length = 2.561±0.44µm), narrowed rearward, with a cytoplasmic canal; and a flagellum (length = 29.521 ±4.37µm). Fertilization tests with thawed semen demonstrated...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Semen characteristics; Cryopreservation; Brycon cephalus; Ultrastructure; Fish.
Ano: 2006
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132006000500015

Cryopreservation of semen from functional sex-reversed genotypic females of the rainbow trout, Oncorhynchus mykiss
Provedor de dados: Brazilian Archives of Biology and Technology
Autores: Ninhaus-Silveira,Alexandre; Foresti,Fausto; Tabata,Yara Aiko; Rigolino,Marcos Guilherme; Veríssimo-Silveira,Rosicleire.
Cryopreservation of semen from sex-reversed females of rainbow trout aims at rationalizing the production of stocks composed by 100% females. Semen from normal males (M) and two types of genotypic females (R and G), sex-reversed by the oral administration of 17alpha-methyltestosterone, were used. R was obtained by the fertilization of normal eggs with semen of sex-reversed females while G via gynogenetic reproduction. Semen was diluted in an extender solution (glucose 5,4 g, egg yolk 10 ml, dimetil sulfoxide 10 ml, water 80 ml) at 1:3 ratio (semen/extender), stored in straws of 0.5 ml and freezed in a dry container Cryopac CP-65, at -180ºC. Thawing was performed with water at 70ºC for 3 seconds. There were no significant fertilization rate differences...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Oncorhynchus mykiss; Cryopreservation; Sex reversal; Gynogenesis; Semen.
Ano: 2006
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132006000100009

Estimated frequency of B-chromosomes and population density of Astyanax scabripinnis paranae in a small stream
Provedor de dados: Brazilian Journal of Genetics
Autores: Porto-Foresti,Fábio; Oliveira,Claudio; Maistro,Edson Luis; Foresti,Fausto.
A study was made of the frequency of B-chromosomes and the population density of Astyanax scabripinnis paranae (Pisces, Characidae, Tetragonopterinae) from three stretches of the Cascatinha stream (Botucatu, SP). In the first stretch the population was estimated to be about 212 individuals and among 35 karyotyped specimens, 23 carried one macro B-chromosome; in the second stretch the population was estimated to be about 650 individuals and among 20 specimens karyotyped, two possessed one macro B-chromosome; in the third stretch the population was estimated to be about 107 individuals and among 10 specimens karyotyped, one carried one macro B-chromosome. A significant difference was observed in the frequency of macro B-chromosomes in females (57%) and males...
Tipo: Info:eu-repo/semantics/article
Ano: 1997
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-84551997000300004