Hypermethylated Chromosome Regions in Nine Fish Species with Heteromorphic Sex Chromosomes

Sites and amounts of 5-methylcytosine (5-MeC)-rich chromosome regions were detected in the karyotypes of 9 Brazilian species of Characiformes fishes by indirect immunofluorescence using a monoclonal anti-5-MeC antibody. These species, belonging to the genera Leporinus, Triportheus and Hoplias, are characterized by highly differentiated and heteromorphic ZW and XY sex chromosomes. In all species, the hypermethylated regions are confined to constitutive heterochromatin. The number and chromosome locations of hypermethylated heterochromatic regions in the karyotypes are constant and species-specific. Generally, heterochromatic regions that are darkly stained by the C-banding technique are distinctly hypermethylated, but several of the brightly fluorescing hypermethylated regions merely exhibit moderate or faint C-banding. The ZW and XY sex chromosomes of all 9 analyzed species also show species-specific heterochromatin hypermethylation patterns. The analysis of 5-MeC-rich chromosome regions contributes valuable data for comparative cytogenetics of closely related species and highlights the dynamic process of differentiation operating in the repetitive DNA fraction of sex chromosomes.

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5-Methylcytosine-Rich Heterochromatin in Reptiles

Cytogenetic and Genome Research ◽

10.1159/000495893 ◽

2019 ◽

Vol 157 (1-2) ◽

pp. 53-64 ◽

Cited By ~ 2

Author(s):

Michael Schmid ◽

Claus Steinlein ◽

Alina M. Reiter ◽

Michail Rovatsos ◽

Marie Altmanová ◽

...

Keyword(s):

Indirect Immunofluorescence ◽

Sex Chromosomes ◽

Dna Sequences ◽

Experimental Approach ◽

Constitutive Heterochromatin ◽

Banding Patterns ◽

Turtle Species ◽

C Banding ◽

Species Specific ◽

Chromosome Regions

An experimental approach using monoclonal anti-5-methylcytosine antibodies and indirect immunofluorescence was elaborated for detecting 5-methylcytosine-rich chromosome regions in reptilian chromosomes. This technique was applied to conventionally prepared mitotic metaphases of 2 turtle species and 12 squamate species from 8 families. The hypermethylation patterns were compared with C-banding patterns obtained by conventional banding techniques. The hypermethylated DNA sequences are species-specific and are located in constitutive heterochromatin. They are highly reproducible and often found in centromeric, pericentromeric, and interstitial positions of the chromosomes. Heterochromatic regions in differentiated sex chromosomes are particularly hypermethylated.

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On sex determination in the Turkish desert woodlouse Hemilepistus elongatus (Crustacea, Isopoda, Oniscidea): searching for sex chromosomes and for sex-specific differences in simple DNA repeats

Genome ◽

10.1139/g96-103 ◽

1996 ◽

Vol 39 (4) ◽

pp. 818-821 ◽

Cited By ~ 3

Author(s):

G. Röder ◽

K. E. Linsenmair ◽

I. Nanda ◽

M. Schmid

Keyword(s):

Chromosome Number ◽

Sex Determination ◽

Sex Chromosomes ◽

Genomic Dna ◽

Constitutive Heterochromatin ◽

Dna Repeats ◽

Male And Female ◽

General Morphology ◽

C Banding ◽

Heteromorphic Sex Chromosomes

The karyotype of male and female Hemilepistus elongatus was investigated by means of C-banding. The diploid chromosome number in both sexes is 2n = 50. By scrutinizing general morphology and localization of the constitutive heterochromatin, no heteromorphic sex chromosomes were found. All chromosome pairs in males are well paired during diakinesis. Hybridization of genomic DNA with (GACA)4 and (GATA)4 oligonucleotides revealed no sex-specific patterns. Key words : karyotype, C-banding, sex determination, simple DNA-repeats, Isopoda.

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The Hypermethylated Regions in Avian Chromosomes

Cytogenetic and Genome Research ◽

10.1159/000464268 ◽

2017 ◽

Vol 151 (4) ◽

pp. 216-227 ◽

Cited By ~ 2

Author(s):

Michael Schmid ◽

Claus Steinlein

Keyword(s):

Sex Chromosomes ◽

Sex Chromosome ◽

Bird Species ◽

Evolutionary Process ◽

General Rule ◽

Centromeric Heterochromatin ◽

Comparative Cytogenetics ◽

Species Specific ◽

Chromosome Segments ◽

Chromosome Regions

Chromosomal locations and amounts of 5-methylcytosine-rich chromosome regions were detected in the karyotypes of 13 bird species by indirect immunofluorescence using a monoclonal anti-5-methylcytosine antibody. These species belong to 7 orders and 10 families of modern (Neognathae) and primitive (Palaeognathae) birds and are characterized by macro- and microchromosomes as well as ZW sex chromosomes. In all 13 species, the hypermethylated chromosome segments are confined to constitutive heterochromatin. The chromosomal locations of hypermethylated DNA regions in the karyotypes are constant and species-specific. There is no general rule with regard to the distribution of these hypermethylated chromosome regions in the genomes of birds. In most instances, hypermethylated segments are located in the centromeric regions of chromosomes, but in the sex chromosomes, these can also be found in telomeric and interstitial postitions. In most of the species studied, the centromeric heterochromatin in many, if not all, of the microchromosomes is hypermethylated. However, in one species, the only detectable hypermethylated heterochromatic regions are located in one pair of macroautosomes and in the Z sex chromosome, but none of the microchromosomes contains visible quantities of 5-methylcytosine. The analysis of 5-methylcytosine-rich chromosome regions can be very helpful for the comparative cytogenetics of closely related species or subspecies. It also reflects the dynamic evolutionary process operating in the highly repetitive DNA of eukaryotic chromosomes.

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Genomic Differences Between the Sexes in a Fish Species Seen Through Satellite DNAs

Frontiers in Genetics ◽

10.3389/fgene.2021.728670 ◽

2021 ◽

Vol 12 ◽

Author(s):

Carolina Crepaldi ◽

Emiliano Martí ◽

Évelin Mariani Gonçalves ◽

Dardo Andrea Martí ◽

Patricia Pasquali Parise-Maltempi

Keyword(s):

Sex Chromosomes ◽

Sex Chromosome ◽

Satellite Dnas ◽

Closely Related Species ◽

Neotropical Fishes ◽

Heteromorphic Sex Chromosomes ◽

Sex Chromosome System ◽

Species Specific ◽

Female Genome ◽

Shed Light

Neotropical fishes have highly diversified karyotypic and genomic characteristics and present many diverse sex chromosome systems, with various degrees of sex chromosome differentiation. Knowledge on their sex-specific composition and evolution, however, is still limited. Satellite DNAs (satDNAs) are tandemly repeated sequences with pervasive genomic distribution and distinctive evolutionary pathways, and investigating satDNA content might shed light into how genome architecture is organized in fishes and in their sex chromosomes. The present study investigated the satellitome of Megaleporinus elongatus, a freshwater fish with a proposed Z1Z1Z2Z2/Z1W1Z2W2 multiple sex chromosome system that encompasses a highly heterochromatic and differentiated W1 chromosome. The species satellitome comprises of 140 different satDNA families, including previously isolated sequences and new families found in this study. This diversity is remarkable considering the relatively low proportion that satDNAs generally account for the M. elongatus genome (around only 5%). Differences between the sexes in regards of satDNA content were also evidenced, as these sequences are 14% more abundant in the female genome. The occurrence of sex-biased signatures of satDNA evolution in the species is tightly linked to satellite enrichment associated with W1 in females. Although both sexes share practically all satDNAs, the overall massive amplification of only a few of them accompanied the W1 differentiation. We also investigated the expansion and diversification of the two most abundant satDNAs of M. elongatus, MelSat01-36 and MelSat02-26, both highly amplified sequences in W1 and, in MelSat02-26’s case, also harbored by Z2 and W2 chromosomes. We compared their occurrences in M. elongatus and the sister species M. macrocephalus (with a standard ZW sex chromosome system) and concluded that both satDNAs have led to the formation of highly amplified arrays in both species; however, they formed species-specific organization on female-restricted sex chromosomes. Our results show how satDNA composition is highly diversified in M. elongatus, in which their accumulation is significantly contributing to W1 differentiation and not satDNA diversity per se. Also, the evolutionary behavior of these repeats may be associated with genome plasticity and satDNA variability between the sexes and between closely related species, influencing how seemingly homeologous heteromorphic sex chromosomes undergo independent satDNA evolution.

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Demonstration of 5-Methylcytosine-Rich DNA Sequences in Chiroptera

Cytogenetic and Genome Research ◽

10.1159/000475740 ◽

2017 ◽

Vol 152 (1) ◽

pp. 38-45 ◽

Cited By ~ 1

Author(s):

Michael Schmid ◽

Claus Steinlein ◽

Christian Lomb ◽

Marianne Volleth

Keyword(s):

Chromosome Number ◽

Repetitive Dna ◽

Dna Sequences ◽

Constitutive Heterochromatin ◽

Metaphase Chromosomes ◽

Valuable Data ◽

Species Specific ◽

Antibody Labeling ◽

Chromosome Segments ◽

Chromosome Regions

5-Methylcytosine-rich heterochromatic regions were demonstrated in metaphase chromosomes of 5 species of Chiroptera by indirect immunofluorescence using a monoclonal anti-5-methylcytosine antibody. These species belong to 4 genera and 2 families and are characterized by divergent karyotypes. One species (Glauconycteris beatrix) has an extremely low diploid chromosome number of 2n = 22 with only meta- to submetacentric elements and remarkably large amounts of constitutive heterochromatin located in the centromeric and pericentromeric regions of all chromosome pairs. Two species (G. beatrix and Neoromicia cf. guineensis) possess X-autosome translocations. In all species, the hypermethylated chromosome segments correspond to constitutive heterochromatin, and the numbers and positions of hypermethylated chromosome segments in the karyotypes are constant and species-specific. In some species (Pipistrellus hesperidus, Neoromicia cf. somalicus), there are several smaller chromosome pairs in which the bright anti-5-methylcytosine antibody labeling is not restricted to constitutively heterochromatic regions but is observed along the whole lengths of these chromosomes. The nature of these additional hypermethylated regions is discussed. The analysis of 5-methylcytosine-rich chromosome regions elucidates valuable data for chiropteran cytogenetics and reflects the high pace of evolution of the repetitive DNA fraction in their genomes.

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Cytogenetical analyses in three fish species of the genus Pimelodus(Siluriformes: Pimelodidae) from rio São Francisco: considerations about the karyotypical evolution in the genus

Neotropical Ichthyology ◽

10.1590/s1679-62252005000200006 ◽

2005 ◽

Vol 3 (2) ◽

pp. 285-290 ◽

Cited By ~ 25

Author(s):

Caroline Garcia ◽

Orlando Moreira Filho

Keyword(s):

Chromosome Pair ◽

Chromosomal Rearrangements ◽

Nucleolar Organizer ◽

Differential Staining ◽

Nucleolar Organizer Regions ◽

C Banding ◽

Heteromorphic Sex Chromosomes ◽

Chromosomal Markers ◽

Staining Techniques ◽

Species Specific

Karyotypes and other chromosomal markers were investigated in three species of the catfish genus Pimelodus, namely P. fur, P. maculatus and Pimelodus sp., from municipality of Três Marias, Minas Gerais, Brazil, using differential staining techniques (C-banding, Silver nitrate and CMA3 staining). The diploid chromosome number was 2n = 56 in P. maculatus and Pimelodus sp., while in P. fur 2n = 54. The karyotype of P. fur consisted in 32M + 8SM + 6ST + 8A with fundamental number (NF) of 100, that of P. maculatus 32M + 12SM + 12A with NF = 112, and that of Pimelodus sp. had 32M + 12Sm + 6ST + 6A with NF = 106.The nucleolar organizer regions (NORs) in all three species were invariably detected in telomeres of longer arm of the 20th chromosome pair. These sites were also positive after CMA3 and C-banding. No heteromorphic sex chromosomes were detected and C-banding pattern was species specific. Inferences about the karyotype differentiation in Pimelodus and putative chromosomal rearrangements are hypohesized.

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CHROMOSOMES AND DNA OF MICROTUS II. CONFIRMATION OF DELETION OF CONSTITUTIVE HETEROCHROMATIN IN M. AGRESTIS CELLS IN VITRO

Canadian Journal of Genetics and Cytology ◽

10.1139/g77-057 ◽

1977 ◽

Vol 19 (3) ◽

pp. 537-541 ◽

Cited By ~ 2

Author(s):

J. E. K. Cooper

Keyword(s):

Somatic Cell ◽

Cell Line ◽

Cell Lines ◽

X Chromosome ◽

Sex Chromosomes ◽

Constitutive Heterochromatin ◽

The Other ◽

Microtus Agrestis ◽

C Banding

The distribution of constitutive heterochromatin has been examined by C-banding in two somatic cell lines, grown in vitro, from a female Microtus agrestis. One line retains one intact X chromosome together with the short arm of the other X chromosome, while the other cell line retains only the short arm of one X chromosome. Thus, each cell line has lost substantial amounts of heterochromatin from the sex chromosomes, but this material has been deleted from the cells, and not translocated to other chromosomes. Nonetheless, both cell lines continue to propagate well in vitro.

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KARYOLOGICAL STUDIES OF A FEMALE VARIABLE OYSTERCATCHER (HAEMATOPUS UNICOLOR)

Canadian Journal of Genetics and Cytology ◽

10.1139/g81-067 ◽

1981 ◽

Vol 23 (4) ◽

pp. 611-619 ◽

Cited By ~ 3

Author(s):

Allan J. Baker ◽

M. Parslow ◽

D. Chambers

Keyword(s):

Sex Chromosomes ◽

Constitutive Heterochromatin ◽

Medium Size ◽

W Chromosome ◽

Valuable Data ◽

Diploid Complement ◽

Embryo Cells

The chromosomes of Haematopus unicolor Forster were examined from cultures of embryo cells. The diploid complement for one individual was estimated to be 2n = 72, comprising 35 autosomes and a pair of sex chromosomes. The W chromosome is a medium size submetacentric. It is smaller than the Z and is the only chromosome with noncentromeric constitutive heterochromatin. The only other species of this genus whose karyotype is known, H. ostralegus, differs from H. unicolor in having a smaller diploid complement (2n = 66) and a telocentric W chromosome. Comparative karyological studies of other species will likely provide valuable data for clarifying the systematics of the Haematopodidae.

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C-banded karyotypes of two Silene species with heteromorphic sex chromosomes

Genome ◽

10.1139/g01-143 ◽

2002 ◽

Vol 45 (2) ◽

pp. 243-252 ◽

Cited By ~ 26

Author(s):

Aleksandra Grabowska-Joachimiak ◽

Andrzej Joachimiak

Keyword(s):

Sex Chromosomes ◽

Sex Chromosome ◽

Silene Latifolia ◽

Silene Dioica ◽

Dna Amount ◽

Metaphase Chromosomes ◽

X Chromosomes ◽

C Banding ◽

Y Chromosomes ◽

Heteromorphic Sex Chromosomes

Mitotic metaphase chromosomes of Silene latifolia (white campion) and Silene dioica (red campion) were studied and no substantial differences between the conventional karyotypes of these two species were detected. The classification of chromosomes into three distinct groups proposed for S. latifolia by Ciupercescu and colleagues was considered and discussed. Additionally, a new small satellite on the shorter arm of homobrachial chromosome 5 was found. Giemsa C-banded chromosomes of the two analysed species show many fixed and polymorphic heterochromatic bands, mainly distally and centromerically located. Our C-banding studies provided an opportunity to better characterize the sex chromosomes and some autosome types, and to detect differences between the two Silene karyotypes. It was shown that S. latifolia possesses a larger amount of polymorphic heterochromatin, especially of the centromeric type. The two Silene sex chromosomes are easily distinguishable not only by length or DNA amount differences but also by their Giemsa C-banding patterns. All Y chromosomes invariably show only one distally located band, and no other fixed or polymorphic bands on this chromosome were observed in either species. The X chromosomes possess two terminally located fixed bands, and some S. latifolia X chromosomes also have an extra-centric segment of variable length. The heterochromatin amount and distribution revealed by our Giemsa C-banding studies provide a clue to the problem of sex chromosome and karyotype evolution in these two closely related dioecious Silene species.Key words: dioecious plant, Silene dioica, Silene latifolia, karyotype, sex chromosomes, heterochromatin, C-banding.

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Comparative cytogenetics in different populations of the cavernicolous diplopod Pseudonannolene strinatii (Diplopoda, Pseudonannolenidae)

Iheringia Série Zoologia ◽

10.1590/s0073-47212013000100006 ◽

2013 ◽

Vol 103 (1) ◽

pp. 42-46

Author(s):

Kleber A. Campos ◽

Carmem S. Fontanetti

Keyword(s):

Silver Nitrate ◽

Constitutive Heterochromatin ◽

Sao Paulo ◽

São Paulo ◽

Comparative Cytogenetics ◽

C Banding ◽

Different Populations

Different populations of Pseudonannolene strinatii Mauriès, 1974 collected from three caves in Iporanga, state of São Paulo, were cytogenetically compared using techniques of conventional coloration, C-banding and silver nitrate impregnation. Specimens were morphologically similar and small cytogenetic differences were observed between the populations with relation to the distribution of constitutive heterochromatin.

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