Nonrandom sex-chromosome association and constitutive heterochromatin in the brush-tailed possum, Trichosurus vulpecula (Marsupialia: Phalangeridae)

1977 ◽  
Vol 18 (2) ◽  
pp. 90-96 ◽  
Author(s):  
J.D. Murray
Keyword(s):  
Constitutive Heterochromatin ◽  
Sex Chromosome ◽  
Chromosome Association ◽  
Trichosurus Vulpecula

scholarly journals Comparative cytogenetics of two species of Dermanura (Chiroptera, Phyllostomidae) in Midwestern Brazil

2021 ◽  
Vol 15 (2) ◽  
pp. 89-99
Author(s):  
Ricardo Firmino de Sousa ◽  
Paulo Cesar Venere ◽  
Karina de Cassia Faria
Keyword(s):  
Diploid Number ◽  
Constitutive Heterochromatin ◽  
Sex Chromosome ◽  
Type System ◽  
Pericentromeric Region ◽  
Morphological Characters ◽  
Comparative Cytogenetics ◽  
Taxonomic Implications ◽  
Sex Chromosome System ◽  
First Time

Dermanura Gervais, 1856 is represented by small frugivorous bats of the Stenodermatinae subfamily. The taxonomy of this group presents controversies and has been subject to changes, especially since the morphological characters evaluated have left gaps that are difficult to fill regarding good species characterization. Previous studies performed in Dermanura cinerea Gervais, 1856 found that the karyotype of this species has a diploid number of chromosomes equal to 30 and 56 autosomal arms. The objective of the present study was to describe, for the first time, the karyotypes of the species Dermanura anderseni (Osgood, 1916) and Dermanura gnoma (Handley, 1987) based on classical cytogenetic markers. For both species, the diploid number found was 2n = 30 and NFa = 56. Two pairs of chromosomes showed markings of the nucleolus organizing regions (AgNORs) in the species D. anderseni and only one pair in D. gnoma, differing from what has already been described for D. cinerea. The two species analyzed here also showed differences in the sex chromosome system, with D. gnoma showing a neo-XY type system while in D. anderseni the classic XY sexual system was observed. In both species, visualization of the constitutive heterochromatin occurred in the pericentromeric region of all chromosomes, as well as in the short arms of the subtelocentric chromosomes. The present work represents an important expansion of karyotypic information for the subfamily Stenodermatinae, bringing chromosomal features that are possible to use in the taxonomic implications of the group.

scholarly journals The sex chromosome association (Sxa) gene is located on the X-chromosome in mice.

1990 ◽  
Vol 65 (2) ◽  
pp. 65-69 ◽  
Author(s):  
Hirotami T. IMAI ◽  
Masayasu Y. WADA ◽  
Kazuo MORIWAKI
Keyword(s):  
X Chromosome ◽  
Sex Chromosome ◽  
Chromosome Association

scholarly journals Differential Expression and Sex Chromosome Association of CHD3/4 and CHD5 during Spermatogenesis

PLoS ONE ◽  
2014 ◽  
Vol 9 (5) ◽  
pp. e98203 ◽  
Author(s):  
Judith W. Bergs ◽  
Nina Neuendorff ◽  
Godfried van der Heijden ◽  
Evelyne Wassenaar ◽  
Peter Rexin ◽  
...  
Keyword(s):  
Differential Expression ◽  
Sex Chromosome ◽  
Chromosome Association

scholarly journals Interspecific chromosomal divergences in the genus Characidium (Teleostei: Characiformes: Crenuchidae)

2010 ◽  
Vol 8 (1) ◽  
pp. 77-86 ◽  
Author(s):  
José Carlos Pansonato Alves ◽  
Luiz Ricardo de Souza Paiva ◽  
Claudio Oliveira ◽  
Fausto Foresti
Keyword(s):  
Chromosome Pair ◽  
Diploid Number ◽  
Constitutive Heterochromatin ◽  
Sex Chromosome ◽  
Way Of Life ◽  
Geographical Isolation ◽  
Relevant Role ◽  
Sex Chromosome System ◽  
Morphological Differences ◽  
First Time

Karyotypes of seven fish species of the genus Characidium, three of them studied for the first time, were characterized using conventional cytogenetic techniques (Giemsa staining, Ag-NOR, and C-banding). All species presented a diploid number of 2n=50, with only metacentric and submetacentric chromosomes, as observed in all Characidium species studied. In two species cells with one to three B chromosomes were observed. All species analyzed have a single NOR-bearing chromosome pair with morphological differences among them. Characidium cf. zebra shows heterochromatic blocks restricted to the pericentromeric regions of all chromosomes denoting the absence of a sex chromosome system. On the other hand, the species Characidium lanei, C. pterostictum, C. lauroi, C. oiticicai, C. schubarti, and Characidium sp., besides presenting pericentromeric heterochromatic blocks, exhibited large interstitial and/or terminal heterochromatic blocks, and a ZZ/ZW sex chromosome system. The constitutive heterochromatin seems to play a relevant role in the chromosome differentiation process of the studied species, mainly in relation to the sex chromosomes. The geographical isolation of the rivers in which the species were sampled, associated with their way of life restricted to headwaters environments, may have favored the process of fixation of different karyotypes found in each of the analyzed species.

scholarly journals CHROMOSOMAL ANALYSIS OF PEROMYSCUS GRATUS (CRICETIDAE) OF TECAMACHALCO, PUEBLA, MEXICO

2020 ◽  
Vol 13 ◽  
Author(s):  
Jesús Martínez-Vázquez ◽  
María De los Ángeles Vela-Montero ◽  
Rosa María González-Monroy
Keyword(s):  
Bone Marrow ◽  
Banding Pattern ◽  
Diploid Number ◽  
Constitutive Heterochromatin ◽  
Sex Chromosome ◽  
Chromosomal Analysis ◽  
Barium Hydroxide ◽  
Chromosome X ◽  
Fundamental Number ◽  
Chromosomal Banding

<p>The description was made of the karyotype of <em>Peromyscus gratus</em> (Cricetidae) in the municipality of Tecamachalco, Puebla. Performing the technique of bone marrow extraction, in the obtention of chromosome, G bands was used Trypsin and for C bands a Barium Hydroxide solution was employed. <em>P</em>. <em>gratus</em> presents a diploid number of 2n = 48 and a fundamental number of NF = 54, the autosomes correspond to one metacentric, one submetacentric, two subtelocentric and 19 pairs telocentric from large to small. The sex chromosome X was subtelocentric and the Y was submetacentric unlike other populations of the species. The chromosomal banding pattern G was obtained. As for chromosome C banding, it was found that the constitutive heterochromatin was in the centromeric regions of the chromosomes.</p>

The role of rDNA genes in X chromosome association in the aphid Acyrthosiphon pisum

Genome ◽  
1999 ◽  
Vol 42 (3) ◽  
pp. 381-386 ◽  
Author(s):  
Mauro Mandrioli ◽  
Davide Bizzaro ◽  
Monica Giusti ◽  
Gian Carlo Manicardi ◽  
Umberto Bianchi
Keyword(s):  
Silver Staining ◽  
Acyrthosiphon Pisum ◽  
Sex Chromosome ◽  
Promoter Sequence ◽  
Aphid Species ◽  
Chromosome Association ◽  
X Chromosomes ◽  
Rdna Genes ◽  
Nucleolar Material

Silver staining of mitotic metaphases of the aphid A. pisum reveals the presence of argentophilic bridges connecting the two X chromosomes. The presence of nucleolar material connecting sex chromosomes seems to be quite a common phenomenon in organisms belonging to very different phyla, and suggests a role of nucleolar proteins in chromosome association and disjunction. In somatic cells of A. pisum, bridges connecting X chromosomes are detectable not only after silver staining but also after CMA3 staining. This finding suggests that GC rich DNA is involved in this type of association. Molecular analysis of rDNA intergenic spacers shows several 247 bp repeats containing short sequences having a high level of homology with the chi sequence of Escherichia coli and with the consensus core region of human hypervariable minisatellites. Moreover, each 247 bp repeat presents a perfect copy of a promoter sequence for polymerase I. These aphid repeats show structural homologies with a 240 bp repeat, which is considered to be responsible for sex chromosome pairing in Drosophila, not only in view of their common presence within rDNA spacers but also for their length and structure. The presence of chi sequences in the IGS of A. pisum, by promoting unequal crossing-over between rDNA genes, could thus give rise to the nucleolar organizing region (NOR) heteromorphism described in different aphid species. Although X pairing at NORs is fundamental in aphid male determination, the presence of heteromorphism of rDNA genes does not inhibit male determination in the A. pisum clone utilized for our experiments.Key words: aphid, rDNA, sex chromosome association, hotspot, NOR heteromorphism.

scholarly journals Comparative cytogenetics of two species of Dermanura (Chiroptera, Phyllostomidae) in Midwestern Brazil

2021 ◽  
Vol 15 (2) ◽  
pp. 89-99
Author(s):  
Ricardo Firmino de Sousa ◽  
Paulo Cesar Venere ◽  
Karina de Cassia Faria
Keyword(s):  
Diploid Number ◽  
Constitutive Heterochromatin ◽  
Sex Chromosome ◽  
Type System ◽  
Pericentromeric Region ◽  
Morphological Characters ◽  
Comparative Cytogenetics ◽  
Taxonomic Implications ◽  
Sex Chromosome System ◽  
First Time

Dermanura Gervais, 1856 is represented by small frugivorous bats of the Stenodermatinae subfamily. The taxonomy of this group presents controversies and has been subject to changes, especially since the morphological characters evaluated have left gaps that are difficult to fill regarding good species characterization. Previous studies performed in Dermanura cinerea Gervais, 1856 found that the karyotype of this species has a diploid number of chromosomes equal to 30 and 56 autosomal arms. The objective of the present study was to describe, for the first time, the karyotypes of the species Dermanura anderseni (Osgood, 1916) and Dermanura gnoma (Handley, 1987) based on classical cytogenetic markers. For both species, the diploid number found was 2n = 30 and NFa = 56. Two pairs of chromosomes showed markings of the nucleolus organizing regions (AgNORs) in the species D. anderseni and only one pair in D. gnoma, differing from what has already been described for D. cinerea. The two species analyzed here also showed differences in the sex chromosome system, with D. gnoma showing a neo-XY type system while in D. anderseni the classic XY sexual system was observed. In both species, visualization of the constitutive heterochromatin occurred in the pericentromeric region of all chromosomes, as well as in the short arms of the subtelocentric chromosomes. The present work represents an important expansion of karyotypic information for the subfamily Stenodermatinae, bringing chromosomal features that are possible to use in the taxonomic implications of the group.

scholarly journals First constitutive heterochromatin characterization and Karyotype of white stork Ciconia ciconia (Aves: Ciconiidae)

2023 ◽  
Vol 83 ◽  
Author(s):  
A. S. M. Abu Shnaf ◽  
M. S. Al-Khalifa
Keyword(s):  
Sex Chromosomes ◽  
Constitutive Heterochromatin ◽  
Sex Chromosome ◽  
Cytogenetic Study ◽  
White Stork ◽  
Sufficient Evidence ◽  
Medium Size ◽  
Ciconia Ciconia ◽  
C Banding ◽  
Autosome Pair

Abstract 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.

Constitutive heterochromatin, 5S and 18S rDNA genes in Apareiodon sp. (Characiformes, Parodontidae) with a ZZ/ZW sex chromosome system

Genetica ◽  
2006 ◽  
Vol 128 (1-3) ◽  
pp. 159-166 ◽  
Author(s):  
Renata da Rosa ◽  
Elisangela Bellafronte ◽  
Orlando Moreira Filho ◽  
Vladimir Pavan Margarido
Keyword(s):  
18S Rdna ◽  
Constitutive Heterochromatin ◽  
Sex Chromosome ◽  
Rdna Genes ◽  
Sex Chromosome System
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