Karyotype and Mapping of Repetitive DNAs in the African Butterfly Fish Pantodon buchholzi, the Sole Species of the Family Pantodontidae

The monophyletic order Osteoglossiformes represents one of the most ancestral groups of teleosts and has at least 1 representative in all continents of the southern hemisphere, with the exception of Antarctica. However, despite its phylogenetic and biogeographical importance, cytogenetic data in Osteoglossiformes are scarce. Here, karyotype and chromosomal characteristics of the lower Niger River population of the African butterfly fish Pantodon buchholzi, the sole species of the family Pantodontidae (Osteoglossiformes), were examined using conventional and molecular cytogenetic approaches. All specimens examined had 2n = 46 chromosomes, with a karyotype composed of 5 pairs of metacentric, 5 pairs of submetacentric, and 13 pairs of acrocentric chromosomes in both sexes. No morphologically differentiated sex chromosomes were identified. C-bands were located in the centromeric/pericentromeric region of all chromosomes and were associated with the single AgNOR site. FISH with ribosomal DNA probes revealed that both 5S and 18S rDNA were present in only 1 pair of chromosomes each, but did not colocalize. CMA3+ bands were observed near the telomeres in several chromosome pairs and also at the 18S rDNA sites. The mapping of di- and trinucleotide repeat motifs, Rex6 transposable element, and U2 snRNA showed a scattered distribution over most of the chromosomes, but for some microsatellites and the U2 snRNA also a preferential accumulation at telomeric regions. This study presents the first detailed cytogenetic analysis in the African butterfly fish by both conventional and molecular cytogenetic protocols. This is the first of a series of further cytogenetic and cytogenomic studies on osteoglossiforms, aiming to comprehensively examine the chromosomal evolution in this phylogenetically important fish order.

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Chromosomal Evolution in Aspredinidae (Teleostei, Siluriformes): Insights on Intra- and Interspecific Relationships with Related Groups

Cytogenetic and Genome Research ◽

10.1159/000511125 ◽

2020 ◽

Vol 160 (9) ◽

pp. 539-553

Author(s):

Milena Ferreira ◽

Isac S. de Jesus ◽

Patrik F. Viana ◽

Caroline Garcia ◽

Daniele A. Matoso ◽

...

Keyword(s):

Evolutionary Dynamics ◽

Sex Chromosome ◽

Chromosomal Evolution ◽

Nucleotide Sequencing ◽

Molecular Cytogenetic ◽

System A ◽

The Family ◽

Sex Chromosome System ◽

Acrocentric Chromosomes ◽

Systematic Relationships

The family Aspredinidae comprises a clade of complex systematic relationships, both from molecular and morphological approaches. In this study, conventional and molecular cytogenetic studies coupled with nucleotide sequencing were performed in 6 Aspredininae species (Amaralia hypsiura, Bunocephalus cf. aloikae, Bunocephalus amaurus, Bunocephalus aff. coracoideus, Bunocephalus verrucosus, and Platystacus cotylephorus) from different locations of the Amazon hydrographic basin. Our results showed highly divergent diploid numbers (2n) among the species, ranging from 49 to 74, including the occurrence of an XX/X0 sex chromosome system. A neighbor-joining phylogram based on the cytochrome c oxidase I (COI) showed that Bunocephalus coracoideus is not a monophyletic clade, but closely related to B. verrucosus. The karyotypic data associated with COI suggest an ancestral karyotype for Aspredinidae with a reduced 2n, composed of bi-armed chromosomes and a trend toward chromosomal fissions resulting in higher diploid number karyotypes, mainly composed of acrocentric chromosomes. Evolutionary relationships were discussed under a phylogenetic context with related species from different Siluriformes families. The karyotype features and chromosomal diversity of Aspredinidae show an amazing differentiation, making this family a remarkable model for investigating the evolutionary dynamics in siluriforms as well as in fish as a whole.

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Contributions to the systematic of Pimelodidae (Osteichthyes, Siluriformes): basic and molecular cytogenetics on seven species of Pimelodus from three Brazilian hydrographic systems

Neotropical Ichthyology ◽

10.1590/1982-0224-20170148 ◽

2018 ◽

Vol 16 (2) ◽

Cited By ~ 2

Author(s):

Simone C. Girardi ◽

Carla S. Pavanelli ◽

Vladimir P. Margarido

Keyword(s):

18S Rdna ◽

Molecular Cytogenetics ◽

5S Rdna ◽

Neotropical Region ◽

Valid Species ◽

Rdna Sites ◽

The Family ◽

Rdna Fish ◽

Pimelodus Maculatus ◽

Cytogenetic Methods

ABSTRACT Pimelodidae harbors several species and is widely distributed throughout the Neotropical region. Pimelodus is the genus with the largest number of species, however it is a polyphyletic group. Cytogenetic analyzes of the valid species still covers less than half of them. Herein, seven Pimelodus species from three Brazilian hydrographic systems were analyzed through basic (Giemsa, AgNORs and C banding) and molecular (5S and 18S rDNA-FISH) cytogenetic methods. All species had 2n=56 chromosomes with different karyotype formulas observed among the species. AgNORs were corresponding to 18S rDNA and localized on long arm of one chromosome pair in all species. Heterochromatin distribution follows the pattern commonly verified in the family and allows to identify each one of the studied species. 5S rDNA marker was interspecifically variable in number and position of cistrons. Pimelodus ortmanni had B chromosomes varying intra and inter-individually. We performed a discussion on our own and available cytogenetic data for Pimelodidae, and the associating of them with available phylogeny enable us identifying features that distinguish subgroups within Pimelodidae, such as NORs location (terminal/long arm for species belonging to “Iheringichthys-Parapimelodus” and “Pimelodus maculatus” subclades) and location of 5S rDNA sites (pericentromeric/interstitial/ long arm for species belonging to Pimelodus group).

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Comparative cytogenetic survey of the giant bonytongue Arapaima fish (Osteoglossiformes: Arapaimidae), across different Amazonian and Tocantins/Araguaia River basins

Neotropical Ichthyology ◽

10.1590/1982-0224-2020-0055 ◽

2020 ◽

Vol 18 (4) ◽

Author(s):

Ezequiel A. de Oliveira ◽

Francisco de M. C. Sassi ◽

Manolo F. Perez ◽

Luiz A. C. Bertollo ◽

Petr Ráb ◽

...

Keyword(s):

River Basins ◽

Comparative Genomic ◽

South American ◽

Molecular Cytogenetic ◽

Araguaia River ◽

Rdna Sites ◽

Cytogenetic Survey ◽

Acrocentric Chromosomes ◽

Great Portion

Abstract The South American giant fishes of the genus Arapaima, commonly known as pirarucu, are one of the most iconic among Osteoglossiformes. Previously cytogenetic studies have identified their karyotype characteristics; however, characterization of cytotaxonomic differentiation across their distribution range remains unknown. In this study, we compared chromosomal characteristics using conventional and molecular cytogenetic protocols in pirarucu populations from the Amazon and Tocantins-Araguaia river basins to verify if there is differentiation among representatives of this genus. Our data revealed that individuals from all populations present the same diploid chromosome number 2n=56 and karyotype composed of 14 pairs of meta- to submetacentric and 14 pairs of subtelo- to acrocentric chromosomes. The minor and major rDNA sites are in separate chromosomal pairs, in which major rDNA sites corresponds to large heterochromatic blocks. Comparative genomic hybridizations (CGH) showed that the genome of these populations shared a great portion of repetitive elements, due to a lack of substantial specific signals. Our comparative cytogenetic data analysis of pirarucu suggested that, although significant genetic differences occur among populations, their general karyotype patterns remain conserved.

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Physical Mapping of the 5S and 18S rDNA in Ten Species ofHypostomusLacépède 1803 (Siluriformes: Loricariidae): Evolutionary Tendencies in the Genus

The Scientific World JOURNAL ◽

10.1155/2014/943825 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8 ◽

Cited By ~ 17

Author(s):

Vanessa Bueno ◽

Paulo César Venere ◽

Jocicléia Thums Konerat ◽

Cláudio Henrique Zawadzki ◽

Marcelo Ricardo Vicari ◽

...

Keyword(s):

18S Rdna ◽

Chromosome Pair ◽

5S Rdna ◽

Pericentromeric Region ◽

Telomeric Region ◽

Diverse Group ◽

Rdna Genes ◽

Rdna Sites ◽

Metacentric Pair

Hypostomusis a diverse group with unclear aspects regarding its biology, including the mechanisms that led to chromosome diversification within the group. Fluorescencein situhybridization (FISH) with 5S and 18S rDNA probes was performed on ten Hypostomini species.Hypostomus faveolus,H. cochliodon,H. albopunctatus,H.aff.paulinus,andH. topavaehad only one chromosome pair with 18S rDNA sites, whileH. ancistroides,H. commersoni,H. hermanni,H. regani,andH. strigaticepshad multiple 18S rDNA sites. Regarding the 5S rDNA genes,H. ancistroides,H. regani,H. albopunctatus,H.aff.paulinus,andH. topavaehad 5S rDNA sites on only one chromosome pair andH. faveolus,H. cochliodon,H. commersoni,H. hermanni,andH. strigaticepshad multiple 5S rDNA sites. Most species had 18S rDNA sites in the telomeric region of the chromosomes. All species butH. cochliodonhad 5S rDNA in the centromeric/pericentromeric region of one metacentric pair. Obtained results are discussed based on existent phylogenies for the genus, with comments on possible dispersion mechanisms to justify the variability of the rDNA sites inHypostomus.

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Comparative cytogenetics of Serrasalmidae (Teleostei: Characiformes): The relationship between chromosomal evolution and molecular phylogenies

PLoS ONE ◽

10.1371/journal.pone.0258003 ◽

2021 ◽

Vol 16 (10) ◽

pp. e0258003

Author(s):

Ramon Marin Favarato ◽

Leila Braga Ribeiro ◽

Alber Campos ◽

Jorge Ivan Rebelo Porto ◽

Celeste Mutuko Nakayama ◽

...

Keyword(s):

Chromosome Number ◽

Chromosomal Rearrangements ◽

5S Rdna ◽

Chromosomal Evolution ◽

Comparative Cytogenetics ◽

Molecular Cytogenetic ◽

The Family ◽

Identification Of Species ◽

Molecular Cytogenetic Techniques ◽

The Relationship

Serrasalmidae has high morphological and chromosomal diversity. Based on molecular hypotheses, the family is currently divided into two subfamilies, Colossomatinae and Serrasalminae, with Serrasalminae composed of two tribes: Myleini (comprising most of pacus species) and Serrasalmini (represented by Metynnis, Catoprion, and remaining piranha’s genera). This study aimed to analyze species of the tribes Myleini (Myloplus asterias, M. lobatus, M. rubripinnis, M. schomburgki, and Tometes camunani) and Serrasalmini (Metynnis cuiaba, M. hypsauchen, and M. longipinnis) using classical and molecular cytogenetic techniques in order to understand the chromosomal evolution of the family. The four species of the genus Myloplus and T. camunani presented 2n = 58 chromosomes, while the species of Metynnis presented 2n = 62 chromosomes. The distribution of heterochromatin occurred predominantly in pericentromeric regions in all species. Tometes camunani and Myloplus spp. presented only one site with 5S rDNA. Multiple markers of 18S rDNA were observed in T. camunani, M. asterias, M. lobatus, M. rubripinnis, and M. schomburgkii. For Metynnis, however, synteny of the 18S and 5S rDNA was observed in the three species, in addition to an additional 5S marker in M. longipinnis. These data, when superimposed on the phylogeny of the family, suggest a tendency to increase the diploid chromosome number from 54 to 62 chromosomes, which occurred in a nonlinear manner and is the result of several chromosomal rearrangements. In addition, the different karyotype formulas and locations of ribosomal sequences can be used as cytotaxonomic markers and assist in the identification of species.

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Molecular Cytogenetic Analysis of Cucumis Wild Species Distributed in Southern Africa: Physical Mapping of 5S and 45S rDNA with DAPI

Cytogenetic and Genome Research ◽

10.1159/000433572 ◽

2015 ◽

Vol 146 (1) ◽

pp. 80-87 ◽

Cited By ~ 6

Author(s):

Kouhei Yagi ◽

Magdalena Pawełkowicz ◽

Paweł Osipowski ◽

Ewa Siedlecka ◽

Zbigniew Przybecki ◽

...

Keyword(s):

Cytogenetic Analysis ◽

Chromosomal Rearrangements ◽

Evolutionary Relationship ◽

Chromosomal Evolution ◽

Rdna Site ◽

45S Rdna ◽

Polyploid Evolution ◽

Molecular Cytogenetic ◽

Rdna Sites ◽

Cucumis Species

Wild Cucumis species have been divided into Australian/Asian and African groups using morphological and phylogenetic characteristics, and new species have been described recently. No molecular cytogenetic information is available for most of these species. The crossability between 5 southern African Cucumis species (C. africanus, C. anguria, C. myriocarpus, C. zeyheri, and C. heptadactylus) has been reported; however, the evolutionary relationship among them is still unclear. Here, a molecular cytogenetic analysis using FISH with 5S and 45S ribosomal DNA (rDNA) was used to investigate these Cucumis species based on sets of rDNA-bearing chromosomes (rch) types I, II and III. The molecular cytogenetic and phylogenetic results suggested that at least 2 steps of chromosomal rearrangements may have occurred during the evolution of tetraploid C. heptadactylus. In step 1, an additional 45S rDNA site was observed in the chromosome (type III). In particular, C. myriocarpus had a variety of rch sets. Our results suggest that chromosomal rearrangements may have occurred in the 45S rDNA sites. We propose that polyploid evolution occurred in step 2. This study provides insights into the chromosomal characteristics of African Cucumis species and contributes to the understanding of chromosomal evolution in this genus.

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Comparative Cytogenetics in Four Leptodactylus Species (Amphibia, Anura, Leptodactylidae): Evidence of Inner Chromosomal Diversification in Highly Conserved Karyotypes

Cytogenetic and Genome Research ◽

10.1159/000515831 ◽

2021 ◽

pp. 1-11

Author(s):

David S. da Silva ◽

Heriberto F. da Silva Filho ◽

Marcelo B. Cioffi ◽

Edivaldo H.C. de Oliveira ◽

Anderson J.B. Gomes

Keyword(s):

18S Rdna ◽

Repetitive Sequences ◽

Molecular Cytogenetics ◽

Comparative Cytogenetics ◽

The Family ◽

Agnor Staining ◽

Dna Elements ◽

Conventional Cytogenetics ◽

Species Specific ◽

Repetitive Dna Elements

With 82 species currently described, the genus Leptodactylus is the most diverse and representative one in the family Leptodactylidae. Concerning chromosomal organization, this genus represents an interesting and underexplored group since data from molecular cytogenetics are incipient, and little is known about the organization and distribution of repetitive DNA elements in the karyotypes. In this sense, this study aimed at providing a comparative analysis in 4 Leptodactylus species (L. macrosternum, L. pentadactylus, L. fuscus, and Leptodactylus cf. podicipinus), combining conventional cytogenetics (Giemsa staining, C-banding, and AgNOR staining) and mapping of molecular markers (18S rDNA, telomeric and microsatellite probes), to investigate mechanisms underlying their karyotype differentiation process. The results showed that all species had karyotypes with 2n = 22 and FN = 44, except for Leptodactylus cf. podicipinus which presented FN = 36. The 18S rDNA was observed in pair 8 of all analyzed species (corresponding to pair 4 in L. pentadactylus), coinciding with the secondary constrictions and AgNOR staining. FISH with microsatellite DNA probes demonstrated species-specific patterns, as well as an association of these repetitive sequences with constitutive heterochromatin blocks and ribosomal DNA clusters, revealing the dynamics of microsatellites in the genome of the analyzed species. In summary, our data demonstrate an ongoing process of genomic divergence inside species with almost similar karyotype, driven most likely by a series of pericentric inversions, followed by differential accumulation of repetitive sequences.

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Comparative Karyotype Investigations in the European Crayfish Astacus astacus and A. leptodactylus (Decapoda, Astacidae)

Crustaceana ◽

10.1163/156854011x607015 ◽

2011 ◽

Vol 84 (12-13) ◽

pp. 1497-1510 ◽

Cited By ~ 7

Author(s):

M. Pavlica ◽

M. Mcžić ◽

G. Klobučar ◽

M. Šrut ◽

I. Maguire ◽

...

Keyword(s):

Chromosome Number ◽

Chromosome Complement ◽

Size Difference ◽

45S Rdna ◽

Astacus Astacus ◽

Fluorochrome Staining ◽

Rdna Sites ◽

Freshwater Habitats ◽

Acrocentric Chromosomes

AbstractThis study reports on the chromosome number and karyological characteristics of the endangered species of European crayfish, Astacus astacus and A. leptodactylus (Decapoda, Astacidae), both native to Croatian freshwater habitats. The karyotype of A. astacus and A. leptodactylus consists of 2n = 176 and 2n = 180 chromosomes, respectively. The haploid chromosome complement of A. astacus consists of 52 metacentric, 35 metacentric-submetacentric, and 1 acrocentric chromosomes. Fluorochrome staining with 4,6-diamino-2-phenylindole (DAPI) has revealed that the karyotypes of A. astacus and A. leptodactylus are characterized by large heterochromatic blocks located at centromeric and intercalary positions on the chromosomes. Interstitial heterochromatic blocks were more frequent in A. astacus than in A. leptodactylus. In both species pairing of chromosomes in meiosis was regular with the majority of bivalents in a ring- and a dumbbell-form. Fluorescence in situ hybridization (FISH) has revealed that two 45S rDNA loci were present in the investigated species. In A. astacus one of the two 45S rDNA-bearing chromosome pairs was highly heteromorphic, exhibiting a three-fold size difference between 45S rDNA sites on homologous chromosomes. Such a size difference was significantly less pronounced in A. leptodactylus. The karyotype differences between A. astacus and A. leptodactylus suggest changes in chromosome number as well as position of repetitive DNAs have played a role in the karyotype evolution of the species of Astacus.

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Jumping Translocations of 1q in Myelodysplastic Syndrome and Acute Myeloid Leukemia: Report of Three Cases and Review of Literature

Case Reports in Genetics ◽

10.1155/2018/8296478 ◽

2018 ◽

Vol 2018 ◽

pp. 1-5 ◽

Cited By ~ 3

Author(s):

T. Couture ◽

K. Amato ◽

A. DiAdamo ◽

P. Li

Keyword(s):

Acute Myeloid Leukemia ◽

Myelodysplastic Syndrome ◽

Myeloid Leukemia ◽

De Novo ◽

Pericentromeric Region ◽

Review Of Literature ◽

Cell Lineages ◽

Chromosome 1Q ◽

Acrocentric Chromosomes ◽

Acute Myeloid

Jumping translocations of 1q refer to the break-off of chromosome 1q as a donor fusing to two or more recipient chromosomes. We detected jumping translocations of 1q in three patients with initial diagnosis of myelodysplastic syndrome (MDS) and later progression to acute myeloid leukemia (AML). Review of literature found jumping translocations of 1q in 30 reported cases of MDS and AML. The cytogenetic findings from these 33 cases showed that seven cases had a stemline clone and 26 cases had de novo jumping translocations of 1q in which 5% of cell lineages had additional structural rearrangements. In 75% of cases, the 1q donor jumped to the short arm of recipient acrocentric chromosomes. Approximately 82% of the fusions occurred in the telomeric regions of short and long arms and 18% occurred in the pericentric or interstitial regions of recipient chromosomes. Hypomethylation of the donor 1q pericentromeric region and shortened telomeres in recipient chromosomes were associated with the formation of jumping translocations. Jumping translocations of 1q as an indication of chromosomal instability pose high risk for progression of MDS to AML and a poor prognosis. Further understanding of underlying genomic defects and their clinical significance will improve overall treatment and patient care.

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New morphological data and molecular diagnostic of Henneguya friderici (Myxozoa: Myxobolidae), a parasite of Leporinus friderici (Osteichthyes: Anostomidae) from southeastern Brazil

Revista Brasileira de Parasitologia Veterinária ◽

10.1590/s1984-29612017010 ◽

2017 ◽

Vol 26 (1) ◽

pp. 81-88 ◽

Cited By ~ 2

Author(s):

Letícia Poblete Vidal ◽

José Luis Luque

Keyword(s):

Body Length ◽

18S Rdna ◽

Genetic Similarity ◽

Morphological Data ◽

Southeastern Brazil ◽

Molecular Diagnostic ◽

Similarity Analysis ◽

Rdna Sequencing ◽

The Family ◽

Gill Filaments

Abstract The myxozoan Henneguya friderici is a parasite of the gills, intestine, kidney and liver of Leporinus friderici, a characiform fish belonging to the family Anostomidae. Forty-two specimens of L. friderici that had been caught in the Mogi Guaçú River, state of São Paulo, were studied. Elongated white plasmodia were found in the gill filaments of 10 host specimens (24%). The mature spores had an ellipsoidal body with polar capsules of equal size and caudal length greater than body length. This study also described 18S rDNA sequencing of H. friderici infecting the gill filaments. This produced a sequence of 1050 bp that demonstrated significant genetic differences with previously described species of Henneguya. Similarity analysis using sequences from species that clustered closest to those produced by this study showed that the species with greatest genetic similarity to H. friderici was H. leporinicola, with 94% similarity.

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