Differentiation of Sex Chromosomes and Karyotype Characterisation in the Dragonsnake Xenodermus javanicus (Squamata: Xenodermatidae)

Highly differentiated heteromorphic ZZ/ZW sex chromosomes with a heterochromatic W are a basic principle among advanced snakes of the lineage Colubroidea, while other snake lineages generally lack these characteristics. For the first time, we cytogenetically examined the dragonsnake, Xenodermus javanicus, a member of the family Xenodermatidae, which is phylogenetically nested between snake lineages with and without differentiated sex chromosomes. Although most snakes have a karyotype with a stable chromosomal number of 2n = 36, the dragonsnake has an unusual, derived karyotype with 2n = 32 chromosomes. We found that heteromorphic ZZ/ZW sex chromosomes with a heterochromatic W are present in the dragonsnake, which suggests that the emergence of a highly differentiated W sex chromosome within snakes predates the split of Xenodermatidae and the clade including families Pareatidae, Viperidae, Homalopsidae, Lamprophiidae, Elapidae, and Colubridae. Although accumulations of interstitial telomeric sequences have not been previously reported in snakes, by using FISH with a telomeric probe we discovered them in 6 pairs of autosomes as well as in the W sex chromosome of the dragonsnake. Similarly to advanced snakes, the sex chromosomes of the dragonsnake have a significant accumulation of repeats containing a (GATA)n sequence. The results facilitate the dating of the differentiation of sex chromosomes within snakes back to the split between Xenodermatidae and other advanced snakes, i.e. around 40-75 mya.

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New evidence for the presence of the telomere motif (TTAGG) n in the family Reduviidae and its absence in the families Nabidae and Miridae (Hemiptera, Cimicomorpha)

Comparative Cytogenetics ◽

10.3897/compcytogen.v13i3.36676 ◽

2019 ◽

Vol 13 (3) ◽

pp. 283-295 ◽

Cited By ~ 5

Author(s):

Snejana Grozeva ◽

Boris A. Anokhin ◽

Nikolay Simov ◽

Valentina G. Kuznetsova

Keyword(s):

Ribosomal Dna ◽

Sex Chromosomes ◽

18S Rdna ◽

Sex Chromosome ◽

Giemsa Staining ◽

Y Chromosomes ◽

The Family ◽

Male Karyotype ◽

First Time ◽

New Evidence

Male karyotype and meiosis in four true bug species belonging to the families Reduviidae, Nabidae, and Miridae (Cimicomorpha) were studied for the first time using Giemsa staining and FISH with 18S ribosomal DNA and telomeric (TTAGG)n probes. We found that Rhynocoris punctiventris (Herrich-Schäffer, 1846) and R. iracundus (Poda, 1761) (Reduviidae: Harpactorinae) had 2n = 28 (24 + X1X2X3Y), whereas Nabis sareptanus Dohrn, 1862 (Nabidae) and Horistus orientalis (Gmelin, 1790) (Miridae) had 2n = 34 (32 + XY) and 2n = 32 (30 + XY), respectively. FISH for 18S rDNA revealed hybridization signals on a sex chromosome, the X or the Y, in H. orientalis, on both X and Y chromosomes in N. sareptanus, and on two of the four sex chromosomes, Y and one of the Xs, in both species of Rhynocoris Hahn, 1834. The results of FISH with telomeric probes support with confidence the absence of the “insect” telomere motif (TTAGG)n in the families Nabidae and Miridae and its presence in both species of genus Rhynocoris of the Reduviidae, considered as a basal family of Cimicomorpha. Increasing evidence reinforces the hypothesis of the loss of the canonical “insect” telomere motif (TTAGG)n by at least four cimicomorphan families, Nabidae, Miridae, Tingidae, and Cimicidae, for which data are currently available.

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Evolution of sex chromosomes is prior to speciation in the dioecious Phoenix species

10.1101/033365 ◽

2015 ◽

Author(s):

Emira Cherif ◽

Salwa Zehdi ◽

Amandine Crabos ◽

Karina Castillo ◽

Nathalie Chabrillange ◽

...

Keyword(s):

Sex Chromosomes ◽

Applied Research ◽

Date Palm ◽

Chromosome Evolution ◽

Sex Chromosome ◽

Driving Forces ◽

Molecular Processes ◽

Dioecious Species ◽

The Family ◽

Suppressed Recombination

Understanding the driving forces and molecular processes underlying dioecy and sex chromosome evolution, leading from hermaphroditism to the occurrence of male and female individuals, is of considerable interest in fundamental and applied research. The genus Phoenix, belonging to the family Arecaceae, consists of only dioecious species. Phylogenetic data suggests that the genus Phoenix diverged from a hermaphroditic ancestor shared with its closest relatives. Here we investigated the evolution of suppressed recombination within the genus Phoenix as a whole by extending the analysis of P. dactylifera sex-related loci to eight other species within the genus. We also performed a phylogenetic analysis of a date palm sex-linked PdMYB1 gene in these species. We found that X and Y sex-linked alleles clustered in a species-independent fashion. Our data show that sex chromosomes evolved before the diversification of the extant dioecious species. Furthermore, the distribution of Y haplotypes revealed two male ancestral paternal lineages which may have emerged prior to speciation.

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Great Abundance of Satellite DNA in Proceratophrys (Anura, Odontophrynidae) Revealed by Genome Sequencing

Cytogenetic and Genome Research ◽

10.1159/000506531 ◽

2020 ◽

Vol 160 (3) ◽

pp. 141-147 ◽

Cited By ~ 1

Author(s):

Marcelo J. da Silva ◽

Raquel Fogarin Destro ◽

Thiago Gazoni ◽

Hideki Narimatsu ◽

Paulo S. Pereira dos Santos ◽

...

Keyword(s):

Repetitive Dna ◽

Sex Chromosomes ◽

Dna Sequences ◽

Satellite Dna ◽

Sex Chromosome ◽

Repetitive Sequences ◽

Centromere Function ◽

Sex Chromosome System ◽

First Time ◽

Eukaryotic Genomes

Most eukaryotic genomes contain substantial portions of repetitive DNA sequences. These are located primarily in highly compacted heterochromatin and, in many cases, are one of the most abundant components of the sex chromosomes. In this sense, the anuran Proceratophrys boiei represents an interesting model for analyses on repetitive sequences by means of cytogenetic techniques, since it has a karyotype with large blocks of heterochromatin and a ZZ/ZW sex chromosome system. The present study describes, for the first time, families of satellite DNA (satDNA) in the frog P. boiei. Its genome size was estimated at 1.6 Gb, of which 41% correspond to repetitive sequences, including satDNAs, rDNAs, transposable elements, and other elements characterized as non-repetitive. The satDNAs were mapped by FISH in the centromeric and pericentromeric regions of all chromosomes, suggesting a possible involvement of these sequences in centromere function. SatDNAs are also present in the W sex chromosome, occupying the entire heterochromatic area, indicating a probable contribution of this class of repetitive DNA to the differentiation of the sex chromosomes in this species. This study is a valuable contribution to the existing knowledge on repetitive sequences in amphibians. We show the presence of repetitive DNAs, especially satDNAs, in the genome of P. boiei that might be of relevance in genome organization and regulation, setting the stage for a deeper functional genome analysis of Proceratophrys.

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A chromosomal investigation of some European species of Haliplidae (Coleoptera)

Memorie della Società Entomologica Italiana ◽

10.4081/memoriesei.2006.173 ◽

2006 ◽

Vol 85 (1) ◽

pp. 173 ◽

Cited By ~ 2

Author(s):

Joseph E. Powell ◽

Robert B. Angus

Keyword(s):

Sex Chromosomes ◽

Sex Chromosome ◽

Good Evidence ◽

European Species ◽

Interspecific Differences ◽

The Family ◽

Sex Chromosome System

The karyotypes of 15 European species of Haliplidae are described and illustrated. The sex chromosomes are X0 in Brychius elevatus and Peltodytes caesus, and XY in 13 species of Haliplus. The number of autosome pairs is 16 in Peltodytes caesus, 19 in Brychius elevatus, 17 in Haliplus (Liaphlus) fulvus, 15 in H. (L.) variegatus, 14 in H. (L.) flavicollis, 11 in H. (L.) laminatus, 9 in H. (L.) mucronatus, and 11 in H. (Haliplidius) obliquus and H. (H.) confinis, H. (Neohaliplus) lineatocollis and five species of H. (Haliplus). It is suggested that the X0 sex chromosome system, the most common in the Adephaga, is plesiotypic for Haliplidae, and that the XY systems are a synapomorphy of the family, and are neo-XY in origin. There is no good evidence of Xyp systems of the type found in Polyphaga. The diversity of karyotypes shown by species of the subgenus Liaphlus is contrasted with the near uniformity shown by other groups. Interspecific differences between karyotypes are noted.

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Chromosomal Mapping of Repetitive DNAs in Myiopsitta monachus and Amazona aestiva (Psittaciformes, Psittacidae) with Emphasis on the Sex Chromosomes

Cytogenetic and Genome Research ◽

10.1159/000464458 ◽

2017 ◽

Vol 151 (3) ◽

pp. 151-160 ◽

Cited By ~ 11

Author(s):

Ivanete de Oliveira Furo ◽

Rafael Kretschmer ◽

Michelly S. dos Santos ◽

Carlos A. de Lima Carvalho ◽

Ricardo J. Gunski ◽

...

Keyword(s):

Sex Chromosomes ◽

Sex Chromosome ◽

Evolutionary Process ◽

Distal Region ◽

Chromosomal Mapping ◽

W Chromosome ◽

Repetitive Dnas ◽

Myiopsitta Monachus ◽

First Time ◽

Whole Chromosome Painting

Here, for the first time, we describe the karyotype of Myiopsitta monachus (Psittacidae, Arini). We found 2n = 48, corresponding to the lowest diploid number observed in Neotropical Psittaciformes so far, with an uncommonly large W chromosome homomorphic to the Z. In order to better understand the evolution of the sex chromosomes in this species, we applied several molecular cytogenetic approaches, including C-banding, FISH mapping of repetitive DNAs (several microsatellite repeats), and whole-chromosome painting on metaphases of M. monachus. For comparison, another species belonging to the same tribe but with a smaller W chromosome (A. aestiva) was also analyzed. The results show that the constitutive heterochromatin has a very diverse distribution pattern in these species revealing heterochromatic blocks in the centromeric region of all chromosomes and in most of the length of the W chromosome in A. aestiva, while in M. monachus they were found in interstitial and telomeric regions. Concerning the microsatellites, only the sequence (CG)n produced signals on the W chromosome of A. aestiva, in the distal region of both arms. However, in M. monachus, (CAA)n, (CAG)n, and (CG)n probes were accumulated on the W chromosome, and, in addition, the sequence (CAG)n also hybridized to heterochromatic regions in macrochromosomes, as well as in microchromosomes. Based on these results, we suggest that the increase in length of the W chromosome in M. monachus is due to the amplification of repetitive elements, which highlights their significant role in the evolutionary process of sex chromosome differentiation.

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Distribution of Telomeric Sequences (TTAGGG)n in Rearranged Chromosomes of Phyllotine Rodents (Cricetidae, Sigmodontinae)

Cytogenetic and Genome Research ◽

10.1159/000444602 ◽

2015 ◽

Vol 147 (4) ◽

pp. 247-252 ◽

Cited By ~ 5

Author(s):

Cecilia Lanzone ◽

Carolina Labaroni ◽

Natalia Suárez ◽

Daniela Rodríguez ◽

Macarena L. Herrera ◽

...

Keyword(s):

Sex Chromosomes ◽

Chromosomal Evolution ◽

Robertsonian Translocations ◽

Telomeric Sequences ◽

Molecular Cytogenetic ◽

Interstitial Telomeric Sequences ◽

Robertsonian Rearrangements ◽

Recent Origin ◽

Chromosome Fusions ◽

Molecular Cytogenetic Techniques

Phyllotines are sigmodontine rodents endemic to South America with broad genetic variability, Robertsonian polymorphisms being the most frequent. Moreover, this taxon includes a species with multiple sex chromosomes, which is infrequent in mammals. However, molecular cytogenetic techniques have never been applied to phyllotines to elucidate their karyotypic evolution. We studied the chromosomes of 4 phyllotine species using FISH with a pantelomeric probe (TTAGGG)n. Graomys griseoflavus, Eligmodontia puerulus, and E. morgani are polymorphic for Robertsonian translocations, whereas Salinomys delicatus possesses XX/ XY1Y2 sex chromosomes. Telomeric signals were detected at both ends of all chromosomes of the studied species. In S. delicatus interstitial telomeric sequences (ITS) were observed in the 3 major chromosome pairs, which are equidistant from one of the telomeres in these chromosomes. These results suggest that ITS are important in the reshuffling of the highly derived karyotype of S. delicatus. Considering the phylogeny of phyllotines, the Robertsonian rearrangements of G. griseoflavus, E. puerulus, and E. morgani possibly represent chromosome fusions which have occurred independently. The pericentromeric regions of the biarmed chromosomes of these species do not contain telomeric sequences characteristic for strict fusions of recent origin, suggesting a common pattern of telomeric repeat loss during chromosomal evolution of these rodents.

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Further data on sex chromosomes of Lacertidae and a hypothesis on their evolutionary trend

Amphibia-Reptilia ◽

10.1163/156853893x00147 ◽

1993 ◽

Vol 14 (1) ◽

pp. 1-11 ◽

Cited By ~ 22

Author(s):

G. Odierna ◽

T. Caprigilone ◽

L.A. Kupriyanova ◽

E. Olmo

Keyword(s):

Sex Chromosomes ◽

Sex Chromosome ◽

Enzyme Treatment ◽

Evolutionary Trend ◽

W Chromosome ◽

Podarcis Sicula ◽

Starting Point ◽

The Family ◽

Podarcis Hispanica ◽

Lacerta Agilis

AbstractSex chromosomes were studied in eight species of lacertid lizards using C-banding, G-banding and restriction enzyme treatment. All of the species showed female heterogamety. The W chromosome was a microchromosome in Lacerta graeca and Ophisops elegans. Two types of W were found in Lacerta vivipara; in specimens from The Netherlands it was metacentric, whereas in specimens from Russia it was acrocentric or subtelocentric. The W chromosome was homomorphic or nearly homomorphic but completely C-banded and heterochromatic in Lacerta agilis, Podarcis hispanica, Algyroides moreoticus and A. nigropunctatus. In was only possible to find sex chromosomes using the G-banding method in Podarcis sicula. The results obtained, together with data in the literature, suggest that sex chromosomes are likely to be present in all Lacertidae and that their differentiation took place repeatedly and independently in different taxa within the family. A model for sex chromosome evolution in the family, in which the starting point was the heterochromatization of the W chromosome, is proposed.

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New cytogenetic data for three species of Pentatomidae (Heteroptera): Dichelops melacanthus (Dallas, 1851), Loxa viridis (Palisot de Beauvois, 1805), and Edessa collaris (Dallas, 1851)

Comparative Cytogenetics ◽

10.3897/compcytogen.v14i4.56743 ◽

2020 ◽

Vol 14 (4) ◽

pp. 577-588

Author(s):

Jaqueline Fernanda Dionísio ◽

Joana Neres da Cruz Baldissera ◽

Angélica Nunes Tiepo ◽

José Antônio Marin Fernandes ◽

Daniel Ricardo Sosa-Gómez ◽

...

Keyword(s):

Sex Chromosomes ◽

18S Rdna ◽

Holocentric Chromosomes ◽

Meiotic Behavior ◽

Rdna Probe ◽

C Banding ◽

Cytogenetic Data ◽

The Family ◽

First Time

In this paper, we present new cytogenetic data for three species of the family Pentatomidae: Dichelops melacanthus (Dallas, 1851), Loxa viridis (Palisot de Beauvois, 1805), and Edessa collaris (Dallas, 1851). All studied species presented holocentric chromosomes and inverted meiosis for the sex chromosomes. D. melacanthus has 2n = 12 (10A + XY); L. viridis showed 2n = 14 (12A + XY); and E. collaris showed 2n = 14 (12A + XY). C-banding was performed for the first time in these species and revealed terminal and interstitial heterochromatic regions on the autosomes; DAPI/CMA3 staining showed different fluorescent patterns. In all species, fluorescence in situ hybridization (FISH) with 18S rDNA probe identified signals on one autosomal bivalent, this being the first report of FISH application in the species D. melacanthus and L. viridis. The results obtained add to those already existing in the literature, enabling a better understanding of the meiotic behavior of these insects.

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New cytogenetic data for three species of Pentatomidae (Heteroptera): Dichelops melacanthus (Dallas, 1851), Loxa viridis (Palisot de Beauvois, 1805), and Edessa collaris (Dallas, 1851)

Comparative Cytogenetics ◽

10.3897/compcytogen.v14.i4.56743 ◽

2020 ◽

Vol 14 (4) ◽

pp. 577-588

Author(s):

Jaqueline Fernanda Dionísio ◽

Joana Neres da Cruz Baldissera ◽

Angélica Nunes Tiepo ◽

José Antônio Marin Fernandes ◽

Daniel Ricardo Sosa-Gómez ◽

...

Keyword(s):

Sex Chromosomes ◽

18S Rdna ◽

Holocentric Chromosomes ◽

Meiotic Behavior ◽

Rdna Probe ◽

C Banding ◽

Cytogenetic Data ◽

The Family ◽

First Time

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Plant genera Cannabis and Humulus share the same pair of well-differentiated sex chromosomes

10.1101/2021.03.11.434957 ◽

2021 ◽

Author(s):

D Prentout ◽

N Stajner ◽

A Cerenak ◽

T Tricou ◽

C Brochier-Armanet ◽

...

Keyword(s):

Sex Chromosomes ◽

Cannabis Sativa ◽

Sex Chromosome ◽

Probabilistic Method ◽

List Type ◽

Recombination Suppression ◽

Sex Chromosome System ◽

The Common ◽

Well Differentiated ◽

First Time

SummaryWe recently described, in Cannabis sativa, the oldest sex chromosome system documented so far in plants. Based on our estimate of its age, we predicted that it should be shared by its sister genus Humulus, which is known to also possess XY sex chromosomes.Here, we used transcriptome sequencing of a F1 family of Humulus lupulus to identify and study the sex chromosomes in this species using the probabilistic method SEX-DETector.We identified 265 sex-linked genes in H. lupulus, located on the chromosome that is also the C. sativa sex chromosome pair. Using phylogenies of sex-linked genes, we show that a region of these chromosomes had already stopped recombining in the common ancestor of the two species. Furthermore, as in C. sativa, Y gene expression was reduced in correlation to the position on the X chromosome, and strongly Y degenerated genes showed dosage compensation.Here we report, for the first time in the Angiosperms, a sex chromosome system that is shared by two different genera. Recombination suppression started at least 21-25 My ago, and then (either gradually or step-wise) spread to a large part of the sex chromosomes, leading to a strongly degenerated Y.

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