Karyotype analysis of three species of Corydoras (Siluriformes: Callichthyidae) from southern Brazil: rearranged karyotypes and cytotaxonomy

ABSTRACT The genus Corydoras comprises a diversity of species with different diploid numbers. We compared cytogenetic data among Corydoras species from different rivers of the Ponta Grossa Arch region in southern Brazil. Corydoras ehrhardti and C. aff. paleatus have a similar karyotype formula and the same diploid number (2n = 44). Corydoras lacrimostigmata has a higher diploid number, with 2n = 58 chromosomes. Fluorescence in situ hybridization using 5S and 18S ribosomal DNA probes suggests that these ribosomal DNA sequences are involved in chromosomal rearrangements in these Corydoras species. 5S rDNA is a chromosomal marker that is considered to be unique to the species analyzed in this study. Signals of interstitial telomeric sites are seen in a chromosome pair of C. lacrimostigmata, suggesting chromosomal rearrangements via fusions or translocations. This study revealed that C. ehrhardti and C. aff. paleatus have exclusive chromosomal markers associated with chromosome differentiation, which we speculate to prevent genetic introgression.

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Phylloporia minuta sp. nov. (Basidiomycota, Hymenochaetales): a remarkable species discovered in a small protected urban area of Atlantic Forest

Phytotaxa ◽

10.11646/phytotaxa.348.3.3 ◽

2018 ◽

Vol 348 (3) ◽

pp. 199

Author(s):

FELIPE BITTENCOURT ◽

SIDNEY LUIZ STÜRMER ◽

MATEUS ARDUVINO RECK ◽

ELISANDRO RICARDO DRECHSLER-SANTOS

Keyword(s):

Phylogenetic Analysis ◽

Urban Area ◽

Atlantic Forest ◽

Ribosomal Dna ◽

Dna Sequences ◽

Protected Area ◽

Southern Brazil ◽

Ecological Data ◽

Black Line ◽

28S Ribosomal Dna

During fungal surveys in a small urban Protected Area in Southern Brazil a species of Phylloporia was found with its minute basidiomata emerging from living stems of Doliocarpus schottianus. It is characterized by pileate and strikingly small basidiomata, context with a black line separating an upper tomentum, 3–7(–8) pores per mm, a monomitic hyphal system and ellipsoid basidiospores. In phylogenetic analysis based on partial nuclear 28S ribosomal DNA sequences, these specimens are resolved as a new clade within Phylloporia. The species is therefore described as P. minuta sp. nov. Ecological data (host and distribution) and the importance of small and urban protected areas are discussed

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New Comparative Cytogenetic Data on Three Genera of Armored Catfishes of Ancistrini (Loricariidae: Hypostominae)

Cytogenetic and Genome Research ◽

10.1159/000504723 ◽

2019 ◽

Vol 159 (4) ◽

pp. 208-214

Author(s):

Sandra Mariotto ◽

Liano Centofante ◽

Paulo C. Venere ◽

Daniela C. Ferreira ◽

Roberto F. Artoni

Keyword(s):

Dna Barcoding ◽

Diploid Number ◽

Chromosomal Rearrangements ◽

5S Rdna ◽

Coi Gene ◽

Published Data ◽

Distance Analysis ◽

C Banding ◽

Mtdna Coi ◽

Rdna Sites

The karyotypes and other chromosomal markers of 4 catfish species, namely Lasiancistrus schomburgkii, Lasiancistrus sp., Araichthysloro, and Megalancistrus sp., members of a taxonomically complex and speciose tribe of catfishes Ancistrini, Hypostominae, were examined using conventional (Giemsa staining, Ag-NOR, and C-banding) and molecular cytogenetic protocols (FISH) and DNA barcoding. In L. schomburgkii, Lasiancistrus sp., and A.loro a diploid number 2n = 54 was observed, with karyotypes composed of 28m + 16sm + 10st, 36m + 12sm + 6st chromosomes, while Megalancistrus sp. had 2n = 52, with the karyotype composed of 28m + 16sm + 8st chromosomes. The Ag-NOR phenotypes were simple in all 4 species, which was confirmed by FISH with an 18S rDNA probe. However, the positive 5S rDNA sites varied among species: 2 chromosome pairs in L. schomburgkii, Lasiancistrus sp., and A. loro, and only 1 pair in Megalancistrus sp. The blocks of constitutive heterochromatin were poorly visible in the pericentromeric and telomeric regions of most chromosomes of the examined species by C-banding. The genetic distance analysis, based on mtDNA COI gene sequences (DNA barcoding), confirmed the species as 4 taxonomic units. Ours and other published data indicate that karyotype differentiation among Ancistrini is complex and divergent and indicates the occurrence of common chromosomal rearrangements, such as pericentric inversions conserving the diploid number, and other rearrangements that are more frequent in some genera, such as centric fusions in Ancistrus.

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Chromosomal characterization and physical mapping of the 5S and the 18S-5.8S-25S ribosomal DNA in Helianthus argophyllus, with new data from Helianthus annuus

Genome ◽

10.1139/g98-112 ◽

1999 ◽

Vol 42 (1) ◽

pp. 110-115 ◽

Cited By ~ 6

Author(s):

T Cuéllar ◽

J Orellana ◽

E Belhassen ◽

J L Bella

Keyword(s):

Ribosomal Dna ◽

Physical Mapping ◽

Dna Sequences ◽

5S Rdna ◽

The Other ◽

Mitotic Chromosomes ◽

Introgression Breeding ◽

C Banding ◽

Interspecific Differences ◽

Secondary Constrictions

The characterization of the mitotic chromosomes of Helianthus argophyllus by means of Feulgen staining, Giemsa C-banding, and the usual DNA sequence-specific fluorochromes allows a chromosomal classification of this species, and shows that two kinds of heterochromatin co-exist equilocally in its chromosomes. One type is confined to the pericentromeric areas of all the chromosomes and the other is associated with the secondary constrictions of the satellite chromosomes. This species is evolutionarily very close to H. annuus with which it is involved in introgression breeding programs. Since these two species show no intra- or interspecific differences with the above treatments, we have used C-banding followed by DAPI, chromomycin A3 or Acridine Orange, and the fluorescent in situ hybridization (FISH) with 5S and 18S-25S ribosomal DNA probes to characterize further the chromosomes of both species in an attempt to find practically applicable chromosomal markers. Our results confirm the heterogeneity of the heterochromatin in these species and show that neither its distribution nor its response to distinct fluorochrome treatments allows better discrimination of the chromosomes within or between the species. On the other hand, the 18S-5.8S-25S rDNA arrays are located in the secondary constrictions of the satellited SM7, SM10, and ST13 pairs and the 5S-rDNA genes are interstitially placed on the short arm of the SM7 and SM11 chromosomes in both species. This permits these chromosomes to be distinguished and provides markers which may be helpful for further physical mapping of DNA sequences in these species.Key words: chromosome banding, sunflower cytogenetics, heterochromatin, ribosomal DNA mapping, FISH.

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Cytogenetic Insights into the Evolution of Chromosomes and Sex Determination Reveal Striking Homology of Turtle Sex Chromosomes to Amphibian Autosomes

Cytogenetic and Genome Research ◽

10.1159/000447478 ◽

2016 ◽

Vol 148 (4) ◽

pp. 292-304 ◽

Cited By ~ 22

Author(s):

Eugenia E. Montiel ◽

Daleen Badenhorst ◽

Ling S. Lee ◽

Robert Literman ◽

Vladimir Trifonov ◽

...

Keyword(s):

Sex Determination ◽

Sex Chromosomes ◽

Diploid Number ◽

Sex Chromosome ◽

Chromosomal Rearrangements ◽

Interspecific Variation ◽

C Banding ◽

Interstitial Telomeric Sites ◽

Secondary Constrictions ◽

Genomic Reorganization

Turtle karyotypes are highly conserved compared to other vertebrates; yet, variation in diploid number (2n = 26-68) reflects profound genomic reorganization, which correlates with evolutionary turnovers in sex determination. We evaluate the published literature and newly collected comparative cytogenetic data (G- and C-banding, 18S-NOR, and telomere-FISH mapping) from 13 species spanning 2n = 28-68 to revisit turtle genome evolution and sex determination. Interstitial telomeric sites were detected in multiple lineages that underwent diploid number and sex determination turnovers, suggesting chromosomal rearrangements. C-banding revealed potential interspecific variation in centromere composition and interstitial heterochromatin at secondary constrictions. 18S-NORs were detected in secondary constrictions in a single chromosomal pair per species, refuting previous reports of multiple NORs in turtles. 18S-NORs are linked to ZW chromosomes in Apalone and Pelodiscus and to X (not Y) in Staurotypus. Notably, comparative genomics across amniotes revealed that the sex chromosomes of several turtles, as well as mammals and some lizards, are homologous to components of Xenopus tropicalis XTR1 (carrying Dmrt1). Other turtle sex chromosomes are homologous to XTR4 (carrying Wt1). Interestingly, all known turtle sex chromosomes, except in Trionychidae, evolved via inversions around Dmrt1 or Wt1. Thus, XTR1 appears to represent an amniote proto-sex chromosome (perhaps linked ancestrally to XTR4) that gave rise to turtle and other amniote sex chromosomes.

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An Insight into the Chromosomal Evolution of Lebiasinidae (Teleostei, Characiformes)

Genes ◽

10.3390/genes11040365 ◽

2020 ◽

Vol 11 (4) ◽

pp. 365 ◽

Cited By ~ 3

Author(s):

Francisco de M. C. Sassi ◽

Terumi Hatanaka ◽

Renata Luiza R. de Moraes ◽

Gustavo A. Toma ◽

Ezequiel A. de Oliveira ◽

...

Keyword(s):

Ribosomal Dna ◽

Dna Sequences ◽

Chromosomal Rearrangements ◽

Repetitive Sequences ◽

Chromosomal Evolution ◽

Genomic Comparison ◽

Terminal Position ◽

Representative Species ◽

Wide Range ◽

Insight Into

Lebiasinidae fishes have been historically neglected by cytogenetical studies. Here we present a genomic comparison in eleven Lebiasinidae species, in addition to a review of the ribosomal DNA sequences distribution in this family. With that, we develop ten sets of experiments in order to hybridize the genomic DNA of representative species from the genus Copeina, Copella, Nannostomus, and Pyrrhulina in metaphase plates of Lebiasina melanoguttata. Two major pathways on the chromosomal evolution of these species can be recognized: (i) conservation of 2n = 36 bi-armed chromosomes in Lebiasininae, as a basal condition, and (ii) high numeric and structural chromosomal rearrangements in Pyrrhulininae, with a notable tendency towards acrocentrization. The ribosomal DNA (rDNA) distribution also revealed a marked differentiation during the chromosomal evolution of Lebiasinidae, since both single and multiple sites, in addition to a wide range of chromosomal locations can be found. With some few exceptions, the terminal position of 18S rDNA appears as a common feature in Lebiasinidae-analyzed species. Altogether with Ctenoluciidae, this pattern can be considered a symplesiomorphism for both families. In addition to the specific repetitive DNA content that characterizes the genome of each particular species, Lebiasina also keeps inter-specific repetitive sequences, thus reinforcing its proposed basal condition in Lebiasinidae.

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Comparative cytogenetics among Leporinus friderici and Leporellus vittatus populations (Characiformes, Anostomidae): focus on repetitive DNA elements

Comparative Cytogenetics ◽

10.3897/compcytogen.v13i2.33764 ◽

2019 ◽

Vol 13 (2) ◽

pp. 105-120 ◽

Cited By ~ 3

Author(s):

Thais Aparecida Dulz ◽

Carla Andrea Lorscheider ◽

Viviane Demetrio Nascimento ◽

Rafael Bueno Noleto ◽

Orlando Moreira-Filho ◽

...

Keyword(s):

Repetitive Dna ◽

Dna Sequences ◽

Chromosomal Rearrangements ◽

5S Rdna ◽

Neotropical Fish ◽

Comparative Cytogenetics ◽

Fish Family ◽

Telomere Sequence ◽

Dna Elements ◽

Chromosomal Changes

Anostomidae are a neotropical fish family rich in number of species. Cytogenetically, they show a conserved karyotype with 2n = 54 chromosomes, although they present intraspecific/interspecific variations in the number and chromosomal location of repetitive DNA sequences. The aim of the present study was to perform a comparative description of the karyotypes of two populations of Leporinusfriderici Bloch, 1794 and three populations of Leporellusvittatus Valenciennes, 1850. We used conventional cytogenetic techniques allied to fluorescence in situ hybridization, using 18S ribosomal DNA (rDNA) and 5S rDNA, a general telomere sequence for vertebrates (TTAGGG)n and retrotransposon (RTE) Rex1 probes. The anostomids in all studied populations presented 2n = 54 chromosomes, with a chromosome formula of 32m + 22sm for L.friderici and 28m + 26sm for L.vittatus. Variations in the number and location of the 5S and 18S rDNA chromosomal sites were observed between L.friderici and L.vittatus populations and species. Accumulation of Rex1 was observed in the terminal region of most chromosomes in all populations, and telomere sequences were located just on all ends of the 54 chromosomes in all populations. The intraspecific and intergeneric chromosomal changes occurred in karyotype differentiation, indicating that minor chromosomal rearrangements had present in anostomid species diversification.

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Ribosomal DNA Sequences of Bifidobacteria: Implications for Sequence-based Identification of the Human Colonic Flora

Microbial Ecology in Health and Disease ◽

10.3402/mehd.v6i1.8088 ◽

1993 ◽

Vol 6 (1) ◽

Author(s):

R. Frothingham ◽

A. J. Duncan ◽

K. H. Wilson

Keyword(s):

Ribosomal Dna ◽

Dna Sequences ◽

Colonic Flora

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Analysis of multiple chromosomal rearrangements in the genome of Willisornis vidua using BAC-FISH and chromosome painting on a supposed conserved karyotype

BMC Ecology and Evolution ◽

10.1186/s12862-021-01768-y ◽

2021 ◽

Vol 21 (1) ◽

Cited By ~ 1

Author(s):

Talita Fernanda Augusto Ribas ◽

Julio Cesar Pieczarka ◽

Darren K. Griffin ◽

Lucas G. Kiazim ◽

Cleusa Yoshiko Nagamachi ◽

...

Keyword(s):

Chromosome Painting ◽

Diploid Number ◽

Chromosomal Rearrangements ◽

Large Degree ◽

Artificial Chromosome ◽

Gallus Gallus ◽

Phylogeographic Structure ◽

Molecular Cytogenetic ◽

Burhinus Oedicnemus ◽

Intrachromosomal Rearrangements

Abstract Background Thamnophilidae birds are the result of a monophyletic radiation of insectivorous Passeriformes. They are a diverse group of 225 species and 45 genera and occur in lowlands and lower montane forests of Neotropics. Despite the large degree of diversity seen in this family, just four species of Thamnophilidae have been karyotyped with a diploid number ranging from 76 to 82 chromosomes. The karyotypic relationships within and between Thamnophilidae and another Passeriformes therefore remain poorly understood. Recent studies have identified the occurrence of intrachromosomal rearrangements in Passeriformes using in silico data and molecular cytogenetic tools. These results demonstrate that intrachromosomal rearrangements are more common in birds than previously thought and are likely to contribute to speciation events. With this in mind, we investigate the apparently conserved karyotype of Willisornis vidua, the Xingu Scale-backed Antbird, using a combination of molecular cytogenetic techniques including chromosome painting with probes derived from Gallus gallus (chicken) and Burhinus oedicnemus (stone curlew), combined with Bacterial Artificial Chromosome (BAC) probes derived from the same species. The goal was to investigate the occurrence of rearrangements in an apparently conserved karyotype in order to understand the evolutionary history and taxonomy of this species. In total, 78 BAC probes from the Gallus gallus and Taeniopygia guttata (the Zebra Finch) BAC libraries were tested, of which 40 were derived from Gallus gallus macrochromosomes 1–8, and 38 from microchromosomes 9–28. Results The karyotype is similar to typical Passeriformes karyotypes, with a diploid number of 2n = 80. Our chromosome painting results show that most of the Gallus gallus chromosomes are conserved, except GGA-1, 2 and 4, with some rearrangements identified among macro- and microchromosomes. BAC mapping revealed many intrachromosomal rearrangements, mainly inversions, when comparing Willisornis vidua karyotype with Gallus gallus, and corroborates the fissions revealed by chromosome painting. Conclusions Willisornis vidua presents multiple chromosomal rearrangements despite having a supposed conservative karyotype, demonstrating that our approach using a combination of FISH tools provides a higher resolution than previously obtained by chromosome painting alone. We also show that populations of Willisornis vidua appear conserved from a cytogenetic perspective, despite significant phylogeographic structure.

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