RESUMO
The karyotype and constitutive heterochromatin pattern of the white stork Ciconia ciconia samples obtained from Manzala lake, Dimiaat, Egypt was described. Somatic cells of Ciconia ciconia samples have diploid number 2n= 68 chromosomes. Out of 68 chromosomes, 11 pairs including sex chromosomes were macrochromosomes and the remaining pairs were microchromosomes. Of the 11 macrochromosome pairs, no.1, 2, 4 and 5 were submetacentric and pairs no. 6, 7 and 8 were described as metacentric. In addition, the autosome pair no.3 was subtelocentric, while autosome pair no.9 was acrocentric. Also, the sex chromosome Z represents the fourth one in size and it was classified as submetacentric while, W chromosome appeared as medium size and was acrocentric. Furthermore, C-banding pattern (constitutive heterochromatin) revealed variation in their sizes and occurrence between macrochromosomes. Pairs no. 7 and 8 of autosomes exhibited unusual distribution of heterochromatin, where they appeared as entirely heterochromatic. This may be related to the origin of sex chromosomes Z and W. However, there is no sufficient evidence illustrate the appearance of entirely heterochromatic autosomes. Therefore, there is no available cytogenetic literature that describes the C-banding and karyotype of Ciconia Ciconia, so the results herein are important and may assist in cytogenetic study and evolutionary pattern of Ciconiiformes.
O cariótipo e o padrão constitutivo de heterocromatina das amostras de cegonha-branca Ciconia ciconia obtidas no lago Manzala, Dimiaat, Egito, foram descritos. As células somáticas de amostras de Ciconia ciconia possuem número diploide 2n = 68 cromossomos. Dos 68 cromossomos, 11 pares incluindo cromossomos sexuais eram macrocromossomos e os pares restantes eram microcromossomos. Dos 11 pares de macrocromossomos, os nos 1, 2, 4 e 5 eram submetacêntricos, e os pares nos 6, 7 e 8 foram descritos como metacêntricos. Além disso, o par de autossomos no 3 era subtelocêntrico, enquanto o par de autossomos no 9 era acrocêntrico. Além disso, o cromossomo sexual Z representa o quarto em tamanho e foi classificado como submetacêntrico, enquanto o cromossomo W apareceu como de tamanho médio e acrocêntrico. Além disso, o padrão de bandamento C (heterocromatina constitutiva) revelou variação em seus tamanhos e ocorrência entre macrocromossomos. Pares nºs 7 e 8 dos autossomos exibiram distribuição incomum de heterocromatina, onde apareceram como totalmente heterocromáticos. Isso pode estar relacionado à origem dos cromossomos sexuais Z e W. No entanto, não há evidências suficientes para ilustrar o aparecimento de autossomos totalmente heterocromáticos. Portanto, não há literatura citogenética disponível que descreva o bandamento C e o cariótipo de Ciconia ciconia, portanto os resultados aqui apresentados são importantes e podem auxiliar no estudo citogenético e no padrão evolutivo de Ciconiiformes.
Assuntos
Animais , Aves/genética , Cariotipagem/veterinária , Heterocromatina/isolamento & purificaçãoRESUMO
The karyotype and constitutive heterochromatin pattern of the white stork Ciconia ciconia samples obtained from Manzala lake, Dimiaat, Egypt was described. Somatic cells of Ciconia ciconia samples have diploid number 2n= 68 chromosomes. Out of 68 chromosomes, 11 pairs including sex chromosomes were macrochromosomes and the remaining pairs were microchromosomes. Of the 11 macrochromosome pairs, no.1, 2, 4 and 5 were submetacentric and pairs no. 6, 7 and 8 were described as metacentric. In addition, the autosome pair no.3 was subtelocentric, while autosome pair no.9 was acrocentric. Also, the sex chromosome Z represents the fourth one in size and it was classified as submetacentric while, W chromosome appeared as medium size and was acrocentric. Furthermore, C-banding pattern (constitutive heterochromatin) revealed variation in their sizes and occurrence between macrochromosomes. Pairs no. 7 and 8 of autosomes exhibited unusual distribution of heterochromatin, where they appeared as entirely heterochromatic. This may be related to the origin of sex chromosomes Z and W. However, there is no sufficient evidence illustrate the appearance of entirely heterochromatic autosomes. Therefore, there is no available cytogenetic literature that describes the C-banding and karyotype of Ciconia Ciconia, so the results herein are important and may assist in cytogenetic study and evolutionary pattern of Ciconiiformes.(AU)
O cariótipo e o padrão constitutivo de heterocromatina das amostras de cegonha-branca Ciconia ciconia obtidas no lago Manzala, Dimiaat, Egito, foram descritos. As células somáticas de amostras de Ciconia ciconia possuem número diploide 2n = 68 cromossomos. Dos 68 cromossomos, 11 pares incluindo cromossomos sexuais eram macrocromossomos e os pares restantes eram microcromossomos. Dos 11 pares de macrocromossomos, os nos 1, 2, 4 e 5 eram submetacêntricos, e os pares nos 6, 7 e 8 foram descritos como metacêntricos. Além disso, o par de autossomos no 3 era subtelocêntrico, enquanto o par de autossomos no 9 era acrocêntrico. Além disso, o cromossomo sexual Z representa o quarto em tamanho e foi classificado como submetacêntrico, enquanto o cromossomo W apareceu como de tamanho médio e acrocêntrico. Além disso, o padrão de bandamento C (heterocromatina constitutiva) revelou variação em seus tamanhos e ocorrência entre macrocromossomos. Pares nºs 7 e 8 dos autossomos exibiram distribuição incomum de heterocromatina, onde apareceram como totalmente heterocromáticos. Isso pode estar relacionado à origem dos cromossomos sexuais Z e W. No entanto, não há evidências suficientes para ilustrar o aparecimento de autossomos totalmente heterocromáticos. Portanto, não há literatura citogenética disponível que descreva o bandamento C e o cariótipo de Ciconia ciconia, portanto os resultados aqui apresentados são importantes e podem auxiliar no estudo citogenético e no padrão evolutivo de Ciconiiformes.(AU)
Assuntos
Animais , Aves/genética , Cariotipagem/veterinária , Heterocromatina/isolamento & purificaçãoRESUMO
Background: Sexual development disturbances (SDD) are divided in SDD with XX genotype (SDD XX) and SDD withXY genotype (SDD XY). Among SDD XY, the Müllers duct persistence syndrome (MDPS) is characterized by XYkaryotype individuals with male external genitals; however, with internal female reproductive organs such as uterine horns,uterus, and cranial vagina portion. The MDPS cases and their related complications are considered very rare in veterinarymedicine. The aim of the present case report is to describe the clinical and pathological aspects of a MDPS case associatedwith cryptorchidism, Sertoli cell tumor, and pyometra in a Miniature Schnauzer dog.Case: A 7-year-old male Miniature Schnauzer weighting 7 kg was brought to veterinary consultation due to owners complain of frequent vomiting, apathy, abdominal algia and progressive scrotal enlargement in the last two months. Physicalexam reveals hyperthermia (39.7°C), discrete dehydration, enlarged popliteal lymph nodes as well as scrotum enlargementwith only one palpable testicle. A blood sample collected for complete blood count showed regenerative anemia, thrombocytopenia, and neutrophilia with left shift in the leukogram. Abdominal ultrasound examination indicated the presenceof a tubular structure filled by anechoic content extending from the scrotum to caudal abdomen. Moreover, a 6.39 x 8.54cm heterogeneous mass in the medial mesogastric region became evident. The patient was hospitalized and submittedto exploratory laparotomy after 24 h due to rectal temperature increase (41°C), worsened abdominal pain, and intenseapathy. There was free purulent liquid in abdominal cavity and two uterine horns were documented. The left uterine hornpasses through inguinal ring and both horns were filled by purulent material...(AU)
Assuntos
Animais , Masculino , Cães , Ductos Paramesonéfricos/anormalidades , Criptorquidismo/veterinária , Tumor de Células de Sertoli/veterinária , Piometra/veterinária , Neoplasias Testiculares/veterinária , Cariotipagem/veterináriaRESUMO
Background: Sexual development disturbances (SDD) are divided in SDD with XX genotype (SDD XX) and SDD withXY genotype (SDD XY). Among SDD XY, the Müllers duct persistence syndrome (MDPS) is characterized by XYkaryotype individuals with male external genitals; however, with internal female reproductive organs such as uterine horns,uterus, and cranial vagina portion. The MDPS cases and their related complications are considered very rare in veterinarymedicine. The aim of the present case report is to describe the clinical and pathological aspects of a MDPS case associatedwith cryptorchidism, Sertoli cell tumor, and pyometra in a Miniature Schnauzer dog.Case: A 7-year-old male Miniature Schnauzer weighting 7 kg was brought to veterinary consultation due to owners complain of frequent vomiting, apathy, abdominal algia and progressive scrotal enlargement in the last two months. Physicalexam reveals hyperthermia (39.7°C), discrete dehydration, enlarged popliteal lymph nodes as well as scrotum enlargementwith only one palpable testicle. A blood sample collected for complete blood count showed regenerative anemia, thrombocytopenia, and neutrophilia with left shift in the leukogram. Abdominal ultrasound examination indicated the presenceof a tubular structure filled by anechoic content extending from the scrotum to caudal abdomen. Moreover, a 6.39 x 8.54cm heterogeneous mass in the medial mesogastric region became evident. The patient was hospitalized and submittedto exploratory laparotomy after 24 h due to rectal temperature increase (41°C), worsened abdominal pain, and intenseapathy. There was free purulent liquid in abdominal cavity and two uterine horns were documented. The left uterine hornpasses through inguinal ring and both horns were filled by purulent material...
Assuntos
Masculino , Animais , Cães , Criptorquidismo/veterinária , Ductos Paramesonéfricos/anormalidades , Neoplasias Testiculares/veterinária , Piometra/veterinária , Tumor de Células de Sertoli/veterinária , Cariotipagem/veterináriaRESUMO
Various species and lineages that until recently were identified as Microsternarchus bilineatus (Hypopomidae, Gymnotiformes) have a widespread distribution in the Amazon and Orinoco River basins and across the Guiana shield. Recent molecular studies show five distinct lineages for Microsternarchus from different localities. These results suggest that this previously monotypic genus actually consists of more than one species. Here, we describe the karyotype of M. aff. bilineatus from the Cururutuia River (Bragança, Pará, Brazil). The diploid number of 48 chromosomes (14 meta-submetacentric/34 subtelo-acrocentric) is found for males and females, with an XX/XY sex chromosome system. The nucleolar organizer region is found in the short arm of pair 9. Constitutive heterochromatin occurs in the pericentromeric region of all chromosomes, in the distal region of 3p, 5p, 7p, 8q, 9q, 16q, and Xq, in the interstitial region in 2p, 10q, 11q, and 12q and all along 4p, and in a large block of the Y chromosome. These results indicate extensive karyotype divergence between this population and samples from Igarapé Tarumã Grande (Negro River, Amazonas, Brazil) studied by other researchers. Moreover, despite the diversity of sex chromosome systems found in Gymnotiformes, the XX/XY sex chromosome system of M. aff. bilineatus is the first case of Y chromosome degeneration in this order. The present data are valuable to help understand karyotype evolution in Hypopomidae.
Assuntos
Evolução Biológica , Gimnotiformes/genética , Cromossomo Y/metabolismo , Animais , Feminino , Cariótipo , Cariotipagem/métodos , Cariotipagem/veterinária , Masculino , FilogeniaRESUMO
We report the first comparative cytogenetic analysis of two species from electrogenic fish of genus Rhabdolichops (Sternopygidae, Gymnotiformes): Rhabdolichops troscheli and Rhabdolichops cf eastwardi. R. troscheli has 2n = 54 (fundamental number [FN] = 66), whereas R. cf. eastwardi has 2n = 74 (FN = 78). C-banding revealed centromeric constitutive heterochromatin in both species. Ag-NORs mapped on pair 6 in R. troscheli and pair 30 in R. cf eastwardi. Fluorescense in situ hybridization with 18S rDNA probes confirmed the Ag-NOR staining results and revealed additional (presumably silent) ribosomal genes on pairs 12, 13, 21, 23, 26, and 27 in R. cf eastwardi. 5S rDNA was found on the centromeres of pair 7 in both species. Telomeric probes showed only distal locations. Dispersed signal patterns were obtained using probes for retrotransposons Rex1 and Rex3. Histone H1 and H3 genes were found together on pair 6 in R. cf eastwardi. The high diploid number found in Rhabdolichops suggests that chromosome fission may have contributed to its chromosomal evolution, phylogenetic relationship of the Sternopygidae suggests that this increase in diploid number could be a synapomorphic characteristic of genus Rhabdolichops. Although both species are phylogenetically close related, their karyotype structure has undergone divergent evolutionary directions. All in all, our results strongly suggest that R. cf eastwardi experencied recent intense genome reorganization.
Assuntos
Análise Citogenética/métodos , Diploide , Gimnotiformes/genética , Animais , Evolução Biológica , Gimnotiformes/classificação , Heterocromatina , Hibridização in Situ Fluorescente/métodos , Cariotipagem/veterináriaRESUMO
Loricariidae family comprises the greatest variability of Neotropical catfish species, with more than 800 valid species. This family shows significant chromosomal diversity. Mapping of repetitive DNA sequences can be very useful in exploring such diversity, especially among groups that appear to share a preserved karyotypic macrostructure. We describe the karyotypes of Panaque armbrusteri and Panaqolus sp., as assessed using classical cytogenetic methods. Moreover, we offer a map of their repetitive sequences, including 18S and 5S ribosomal DNAs, the Rex1 and Rex3 retrotransposons, and the Tc1-mariner transposon in P. armbrusteri, Panaqolus sp., Scobinancistrus aureatus, and Scobinancistrus pariolispos. Those species share chromosome numbers of 2n = 52, but are divergent in their chromosome structures and the distributions of their repetitive DNA sequences. In situ hybridization with 18S and 5S rDNA probes confirms chromosome location in different pairs; in Panaqolus sp. these sites are in synteny. This multigene family organization can be explained by the occurrence of chromosome rearrangements, and possible events, such as transposition and unequal crossing-over. Rex1 and Rex3 retrotransposons and the Tc1-mariner transposon appeared predominantly dispersed and in small clusters in some chromosome regions. These data emphasize the importance of repetitive sequences in promoting the karyotypic evolution of these species.
Assuntos
Peixes-Gato/classificação , Peixes-Gato/genética , Evolução Molecular , Sequências Repetitivas de Ácido Nucleico , Animais , Brasil , Mapeamento Cromossômico , DNA Ribossômico , Variação Genética , Cariotipagem/veterinária , RNA Ribossômico 18S/genética , RNA Ribossômico 5S/genética , RetroelementosRESUMO
Karyotypes and other chromosomal markers as revealed by conventional and molecular cytogenetic protocols in four species of the catfish family Doradidae from the Araguaia-Tocantins river basin, namely Hassar wilderi, Leptodoras cataniae, Tenellus leporhinus and Tenellus trimaculatus were examined. All species had diploid chromosome number 2n = 58 and karyotypes dominated by biarmed chromosomes, simple NOR phenotype, that is, one chromosome pair bearing this site in terminal position, but some differences in karyotypes and distribution of constitutive heterochromatin, position of rDNA sites. Such characteristics appeared species-specific. A ZZ/ZW sex chromosome system was found in Tenellus trimaculatus, resulting likely from the amplification of the heterochromatin, followed by a paracentric inversion. Our results confirmed low karyotype differentiation observed until now among representatives of this endemic catfish family.
Assuntos
Peixes-Gato/genética , Heterocromatina , Cariotipagem/veterinária , Cromossomos Sexuais/fisiologia , Animais , Peixes-Gato/classificação , DNA Ribossômico/genética , Feminino , Cariótipo , Cariotipagem/métodos , Masculino , Especificidade da EspécieRESUMO
Hoplias malabaricus comprises seven karyomorphs (A-G) and evolutionary units have been described in some of them. In this study, the karyotypic composition and genomic organization of individual H. malabaricus from Central Amazon are described and to verify whether they can be classified according to known karyomorphs. Individuals from the Ducke Reserve have 2n = 42 chromosomes, similar to karyomorph A. Individuals from Catalão Lake and Marchantaria Island exhibit 2n = 40 chromosomes, similar to karyomorph C. Regarding the constitutive heterochromatin, individuals from all locations present centromeric/pericentromeric blocks, in addition to some bitelomeric and interstitial markings. The number of chromosomes with nucleolar organizer region, 5S rDNA and 18S rDNA sites varied among the different locations. The Rex 3 element has a compartmentalized distribution at the terminal and centromeric regions of most chromosomes, with subtle differences among populations. Fluorescence in situ hybridization performed with a telomeric probe allowed the detection of these regions only at the terminal ends of the chromosomes. Thus, only the chromosomal macrostructure (karyomorphs A-G) is not sufficient to establish evolutionary units within the H. malabaricus group, considering differences in the genome organization that are found among their populations. Such differences in the genomic organization could be mainly caused by the sedentary habits of this species.