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Registros recuperados: 20 | |
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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 |
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Bellafronte,Elisangela; Schemberger,Michelle Orane; Artoni,Roberto Ferreira; Moreira Filho,Orlando; Vicari,Marcelo Ricardo. |
Parodontidae fish show few morphological characteristics for the identification of their representatives and chromosomal analyses have provided reliable features for determining the interrelationships in this family. In this study, the chromosomes of Apareiodon hasemani from the São Francisco River basin, Brazil, were analyzed and showed a karyotype with 2n = 54 meta/submetacentric chromosomes, and a ZZ/ZW sex chromosome system. The study revealed active NORs located on pair 11 and additional 18S rDNA sites on pairs 7 and 22. The 5S rDNA locus was found in pair 14. It showed a pericentric inversion regarding the ancestral condition. The satellite DNA pPh2004 was absent in the chromosomes of A. hasemani, a shared condition with most members of Apareiodon.... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cytogenetics; FISH; 18S rDNA; 5S rDNA; Neotropical fishes. |
Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572012000500010 |
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Ribeiro,Leila Braga; Matoso,Daniele Aparecida; Feldberg,Eliana. |
The Serrasalmidae family is composed of a number of commercially interesting species, mainly in the Amazon region where most of these fishes occur. In the present study, we investigated the genomic organization of the 18S and 5S rDNA and telomeric sequences in mitotic chromosomes of four species from the basal clade of the Serrasalmidae family: Colossoma macropomum, Mylossoma aureum, M. duriventre, and Piaractus mesopotamicus, in order to understand the chromosomal evolution in the family. All the species studied had diploid numbers 2n = 54 and exclusively biarmed chromosomes, but variations of the karyotypic formulas were observed. C-banding resulted in similar patterns among the analyzed species, with heterochromatic blocks mainly present in centromeric... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: 5S rDNA; Telomeric sequences; Tambaqui and pacu. |
Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572014000100009 |
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Aguilar,Cecilia Teixeira de; Galetti Junior,Pedro Manoel. |
Among the anostomid fishes, the genus Leporellus is represented by only three species: L. nattereri, endemic of the Amazon River, L. retropinnis, endemic of the Piracicaba River, and L. vittatus, widely distributed in rivers from Peru, Colombia, Guianas, and different major hydrographic basins of Brazil. A cytogenetic study carried out on specimens of Leporellus vittatus from three major Brazilian hydrographic basins evidenced a karyotype of 54 metacentric and submetacentric chromosomes. C-banding analysis revealed the presence of large pericentromeric heterochromatic segments in all chromosomes and a telomeric block coincident with the NOR sites. Ag, CMA3 or MM staining, and FISH with ribosomal probes located the 45S ribosomal genes on the terminal region... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Karyotype; C-bands; 45S rDNA; 5S rDNA. |
Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572008000200004 |
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Santos,Dayane Petik dos; Felicetti,Denise; Baumgärtner,Lucas; Margarido,Vladimir Pavan; Blanco,Daniel Rodrigues; Moreira-Filho,Orlando; Lui,Roberto Laridondo. |
ABSTRACT Auchenipteridae is divided into subfamilies Centromochlinae and Auchenipterinae. Parauchenipterus is included in the latter and is subject of taxonomic discussions concerning its validation or synonymization with Trachelyopterus. Herein, three species from two hydrographic basins were cytogenetically analyzed: Parauchenipterus striatulus from Doce River and two sympatric species, P. galeatus and Trachelyopterus coriaceus, from the Araguaia River. Diploid number of 58 chromosomes was verified for all species, but P. striatulus has different karyotype formula from the others. The three species have heterochromatin located in terminal regions of almost all chromosomes and in pericentromeric region on acrocentric chromosomes. Simple NORs was verified... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cryptic species; FISH; Parauchenipterus; Problematic taxonomy; 5S rDNA. |
Ano: 2021 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252021000100214 |
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Barreto,Silvia B.; Cioffi,Marcelo B.; Medrado,Aline S.; Silva,André T.; Affonso,Paulo R. A. M.; Diniz,Débora. |
ABSTRACT Characiformes is the most cytogenetically studied group of freshwater Actinopterygii, but karyotypical data of several taxa remain unknown. This is the case of Nematocharax , regarded as a monotypic genus and characterized by marked sexual dimorphism. Therefore, we provide the first cytogenetic report of allopatric populations of Nematocharax venustus based on distinct methods of chromosomal banding and fluorescence in situ hybridization (FISH) with repetitive DNA probes (18S and 5S rDNA). The karyotype macrostructure was conserved in all specimens and populations, independently on sex, since they shared a diploid number (2n) of 50 chromosomes divided into 8m+26sm+14st+2a. The heterochromatin was mainly distributed at pericentromeric regions and... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: 18S rDNA; 5S rDNA; Coastal drainages; FISH; Population cytogenetics. |
Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252016000200205 |
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Hett,Anne Kathrin; Nirchio,Mauro; Oliveira,Claudio; Siccha,Zoila Raquel; Rossi,Anna Rita; Sola,Luciana. |
This study reports the description of the karyotype of Mugil incilis from Venezuela. The chromosome complement is composed of 48 acrocentric chromosomes, which uniformly decrease in size. Therefore, the homologues can not be clearly identified, with the exception of one of the largest chromosome pairs, classified as number 1, whose homologues may show a subcentromeric secondary constriction, and of chromosome pair number 24, which is considerably smaller than the others. C-banding showed heterochromatic blocks at the centromeric/pericentromeric regions of all chromosomes, which were more conspicuous on chromosomes 1, given the C-positive signals include the secondary constrictions. AgNO3 and fluorescent in situ hybridization (FISH) with 45S rDNA... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: C-banding; COI; 5S rDNA; Mullet; NORs. |
Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252011000100008 |
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Konerat,Jocicléia Thums; Bueno,Vanessa; Baumgartner,Lucas; Martins-Santos,Isabel Cristina; Margarido,Vladimir Pavan. |
B chromosomes are extra chromosomes from the normal chromosomal set, found in different organisms, highlighting their presence on the group of fishes. Callichthys callichthys from the upper Paraná River has a diploid number of 56 chromosomes (26 m-sm + 30 st-a) for both sexes, with the presence of a sporadically acrocentric B chromosome. Moreover, one individual presented a diploid number of 57 chromosomes, with the presence of a morphologically ill-defined acrocentric B chromosome in all analyzed cells. The physical mapping of 5S and 18S rDNA shows multiple 5S rDNA sites and only one pair of chromosomes with 18S sites in C. callichthys, except for two individuals. These two individuals presented a third chromosome bearing NORs (Ag-staining and 18S rDNA)... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: 18S rDNA; 5S rDNA; Chromosomal rearrangements; FISH; Supernumerary chromosome. |
Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252014000300603 |
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Hwang,Yoon-Jung; Song,Chang-Min; Younis,Adnan; Kim,Chang-Kil; Kang,Yoon-Im; Lim,Ki-Byung. |
BACKGROUND: This study was performed to investigate the phenotypic, karyomorphological, and habitat environment characteristics of Lilium distichum that grows naturally in South Korea. Currently, this species follows limited distribution areas and its natural populations are at the brink of extinction mainly due to fragmentation or destruction its natural habitat. RESULTS: This species was distributed between approximately 1,000 and 1,500 m above sea level with an average temperature of 22°C. The soil characteristics surrounding the natural habitats included loamy and silt loam soils having organic matter content (10.82%), pH (5.22), electrical conductivity (EC) (0.37 dS/m), total nitrogen (0.45%), and cation exchange capacity (34.3 cmol+/kg). The peak... |
Tipo: Journal article |
Palavras-chave: Chromosome; Karyotype; Habitat; Korea; 5S rDNA; 45S rDNA. |
Ano: 2015 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2015000100008 |
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Registros recuperados: 20 | |
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