Observations on centromeric heterochromatin and satellite DNA in salamanders of the genus Plethodon

Chromosoma ◽  
1973 ◽  
Vol 43 (4) ◽  
pp. 329-348 ◽  
Author(s):  
H. C. Macgregor ◽  
Heather Horner ◽  
C. A. Owen ◽  
I. Parker
Keyword(s):  
Satellite Dna ◽  
Centromeric Heterochromatin

scholarly journals Chromosomal G-dark Bands Determine the Spatial Organization of Centromeric Heterochromatin in the Nucleus

2001 ◽  
Vol 12 (11) ◽  
pp. 3563-3572 ◽  
Author(s):  
Célia Carvalho ◽  
Henrique M. Pereira ◽  
João Ferreira ◽  
Cristina Pina ◽  
Denise Mendonça ◽  
...  
Keyword(s):  
Satellite Dna ◽  
Spatial Organization ◽  
Nuclear Periphery ◽  
Three Dimensional ◽  
Lymphoid Cells ◽  
Spatial Proximity ◽  
Centromeric Heterochromatin ◽  
Chromosome 11 ◽  
Cis Acting ◽  
Tight Correlation

Gene expression can be silenced by proximity to heterochromatin blocks containing centromeric α-satellite DNA. This has been shown experimentally through cis-acting chromosome rearrangements resulting in linear genomic proximity, or throughtrans-acting changes resulting in intranuclear spatial proximity. Although it has long been been established that centromeres are nonrandomly distributed during interphase, little is known of what determines the three-dimensional organization of these silencing domains in the nucleus. Here, we propose a model that predicts the intranuclear positioning of centromeric heterochromatin for each individual chromosome. With the use of fluorescence in situ hybridization and confocal microscopy, we show that the distribution of centromeric α-satellite DNA in human lymphoid cells synchronized at G0/G1is unique for most individual chromosomes. Regression analysis reveals a tight correlation between nuclear distribution of centromeric α-satellite DNA and the presence of G-dark bands in the corresponding chromosome. Centromeres surrounded by G-dark bands are preferentially located at the nuclear periphery, whereas centromeres of chromosomes with a lower content of G-dark bands tend to be localized at the nucleolus. Consistent with the model, a t(11; 14) translocation that removes G-dark bands from chromosome 11 causes a repositioning of the centromere, which becomes less frequently localized at the nuclear periphery and more frequently associated with the nucleolus. The data suggest that “chromosomal environment” plays a key role in the intranuclear organization of centromeric heterochromatin. Our model further predicts that facultative heterochromatinization of distinct genomic regions may contribute to cell-type specific patterns of centromere localization.

scholarly journals A new family of satellite DNA sequences as a major component of centromeric heterochromatin in owls (Strigiformes)

Chromosoma ◽  
2004 ◽  
Vol 112 (7) ◽  
pp. 372-373 ◽  
Author(s):  
Kazuhiko Yamada ◽  
Chizuko Nishida-Umehara ◽  
Yoichi Matsuda
Keyword(s):  
Dna Sequences ◽  
Satellite Dna ◽  
Centromeric Heterochromatin ◽  
New Family

scholarly journals Mouse satellite DNA, centromere structure, and sister chromatid pairing.

1986 ◽  
Vol 103 (4) ◽  
pp. 1145-1151 ◽  
Author(s):  
L M Lica ◽  
S Narayanswami ◽  
B A Hamkalo
Keyword(s):  
Electron Microscopy ◽  
Sister Chromatid ◽  
Satellite Dna ◽  
Marker Chromosome ◽  
Restriction Enzymes ◽  
Centromeric Heterochromatin ◽  
Mitotic Chromosomes ◽  
Metaphase Chromosomes ◽  
Sister Chromatids ◽  
Mouse Satellite Dna

The experiments described were directed toward understanding relationships between mouse satellite DNA, sister chromatid pairing, and centromere function. Electron microscopy of a large mouse L929 marker chromosome shows that each of its multiple constrictions is coincident with a site of sister chromatid contact and the presence of mouse satellite DNA. However, only one of these sites, the central one, possesses kinetochores. This observation suggests either that satellite DNA alone is not sufficient for kinetochore formation or that when one kinetochore forms, other potential sites are suppressed. In the second set of experiments, we show that highly extended chromosomes from Hoechst 33258-treated cells (Hilwig, I., and A. Gropp, 1973, Exp. Cell Res., 81:474-477) lack kinetochores. Kinetochores are not seen in Miller spreads of these chromosomes, and at least one kinetochore antigen is not associated with these chromosomes when they were subjected to immunofluorescent analysis using anti-kinetochore scleroderma serum. These data suggest that kinetochore formation at centromeric heterochromatin may require a higher order chromatin structure which is altered by Hoechst binding. Finally, when metaphase chromosomes are subjected to digestion by restriction enzymes that degrade the bulk of mouse satellite DNA, contact between sister chromatids appears to be disrupted. Electron microscopy of digested chromosomes shows that there is a significant loss of heterochromatin between the sister chromatids at paired sites. In addition, fluorescence microscopy using anti-kinetochore serum reveals a greater inter-kinetochore distance than in controls or chromosomes digested with enzymes that spare satellite. We conclude that the presence of mouse satellite DNA in these regions is necessary for maintenance of contact between the sister chromatids of mouse mitotic chromosomes.

scholarly journals Identification of a subdomain of CENP-B that is necessary and sufficient for localization to the human centromere.

1992 ◽  
Vol 116 (5) ◽  
pp. 1081-1093 ◽  
Author(s):  
A F Pluta ◽  
N Saitoh ◽  
I Goldberg ◽  
W C Earnshaw
Keyword(s):  
Satellite Dna ◽  
Centromeric Heterochromatin ◽  
Amino Terminus ◽  
Major Protein ◽  
Alpha Satellite ◽  
Alpha Satellite Dna ◽  
Human Centromere ◽  
Bacterial Enzyme

We have combined in vivo and in vitro approaches to investigate the function of CENP-B, a major protein of human centromeric heterochromatin. Expression of epitope-tagged deletion derivatives of CENP-B in HeLa cells revealed that a single domain less than 158 residues from the amino terminus of the protein is sufficient to localize CENP-B to centromeres. Centromere localization was abolished if as few as 28 amino acids were removed from the amino terminus of CENP-B. The centromere localization signal of CENP-B can function in an autonomous fashion, relocating a fused bacterial enzyme to centromeres. The centromere localization domain of CENP-B specifically binds in vitro to a subset of alpha-satellite DNA monomers. These results suggest that the primary mechanism for localization of CENP-B to centromeres involves the recognition of a DNA sequence found at centromeres. Analysis of the distribution of this sequence in alpha-satellite DNA suggests that CENP-B binding may have profound effects on chromatin structure at centromeres.

Karyotype characterization of the lake sturgeon, Acipenser fulvescens (Rafinesque 1817) by chromosome banding and fluorescent in situ hybridization

Genome ◽  
2004 ◽  
Vol 47 (4) ◽  
pp. 742-746 ◽  
Author(s):  
Francesco Fontana ◽  
Ronald M Bruch ◽  
Fred P Binkowski ◽  
Massimo Lanfredi ◽  
Milvia Chicca ◽  
...  
Keyword(s):  
In Situ Hybridization ◽  
Satellite Dna ◽  
Fluorescent In Situ Hybridization ◽  
Lake Sturgeon ◽  
Centromeric Heterochromatin ◽  
Telomeric Sequence ◽  
Acipenser Fulvescens ◽  
Nucleolar Organizer Regions ◽  
C Banding

A karyotype analysis using several staining techniques was carried out on the North American lake sturgeon, Acipenser fulvescens. The chromosome number was found to be 2n = 262 ± 6. A representative karyotype of 264 chromosomes was composed of 134 meta- and submetacentrics, 70 telo- and acrocentrics, and 60 microchromosomes. The constitutive heterochromatin, revealed by C banding, was localized in various positions on several chromosomes, including microchromosomes. The signals of fluorescent in situ hybridization (FISH) with a HindIII satellite DNA probe were visible as centromeric heterochromatin blocks on 48 chromosomes. The telomeric repeat (TTAGGG)n detected by FISH was localized at both ends of all chromosomes and two chromosomes were entirely marked. Fluorescent staining with GC-specific chromomycin A3 showed recognizable fluorescent regions, whereas a more uniform base composition was revealed by the AT-specific 4',6-diamidino-2-phenylindole (DAPI). After silver staining, the active nucleolar organizer regions (NORs) were detected on 12 chromosomes. FISH with the 5S probe showed four signals on four small chromosomes. Our data suggest that A. fulvescens is a tetraploid species.Key words: karyotype, C banding, telomeric sequence, fluorochrome staining, satellite DNA, 5S rDNA.

CHARACTERIZATION OF HUMAN CHROMOSOMAL CONSTITUTIVE HETEROCHROMATIN

2020 ◽  
Vol 53 (02) ◽  
pp. 08-11
Author(s):  
Aytakin Hasanova
Keyword(s):  
Satellite Dna ◽  
Constitutive Heterochromatin ◽  
Chromosome Breakage ◽  
Centromeric Heterochromatin ◽  
Crossing Over ◽  
Alpha Satellite ◽  
Alpha Satellite Dna ◽  
Chromosome Regions ◽  
Chromosome Disjunction

Heterochromatin of centromeric chromosome regions contains late replicating, largely repetitive DNA. It is suggested that heterochromatin participates in chromosome pairing, crossing-over and in chromosome disjunction control (1,3). Centromeric heterochromatin, a variety of heterochromatin, is a tightly packed form of DNA.Centromeric heterochromatin is a constituent in the formation ofactive centromeres in most higher-order organisms; the domain exists on both mitotic and interphase chromosomes. (4,5,6,8) Centromeric heterochromatin is usually formed on alpha satellite DNA in humans; however, there have been cases where centric heterochromatin and centromeres have formed on originally euchromatin domains lacking alpha satellite DNA; this usually happens as a result of a chromosome breakage event and the formed centromere is called a neocentromere.

Satellite DNA Sequences in Canidae and Their Chromosome Distribution in Dog and Red Fox

2016 ◽  
Vol 150 (2) ◽  
pp. 118-127 ◽  
Author(s):  
Miluse Vozdova ◽  
Svatava Kubickova ◽  
Halina Cernohorska ◽  
Jan Fröhlich ◽  
Jiri Rubes
Keyword(s):  
Dna Sequences ◽  
Satellite Dna ◽  
Red Fox ◽  
In Situ Hybridisation ◽  
B Chromosomes ◽  
Domestic Dog ◽  
Centromeric Heterochromatin ◽  
Arctic Fox ◽  
Nyctereutes Procyonoides ◽  
Fluorescence In Situ Hybridisation

Satellite DNA is a characteristic component of mammalian centromeric heterochromatin, and a comparative analysis of its evolutionary dynamics can be used for phylogenetic studies. We analysed satellite and satellite-like DNA sequences available in NCBI for 4 species of the family Canidae (red fox, Vulpes vulpes, VVU; domestic dog, Canis familiaris, CFA; arctic fox, Vulpes lagopus, VLA; raccoon dog, Nyctereutes procyonoides procyonoides, NPR) by comparative sequence analysis, which revealed 86-90% intraspecies and 76-79% interspecies similarity. Comparative fluorescence in situ hybridisation in the red fox and dog showed signals of the red fox satellite probe in canine and vulpine autosomal centromeres, on VVUY, B chromosomes, and in the distal parts of VVU9q and VVU10p which were shown to contain nucleolus organiser regions. The CFA satellite probe stained autosomal centromeres only in the dog. The CFA satellite-like DNA did not show any significant sequence similarity with the satellite DNA of any species analysed and was localised to the centromeres of 9 canine chromosome pairs. No significant heterochromatin block was detected on the B chromosomes of the red fox. Our results show extensive heterogeneity of satellite sequences among Canidae and prove close evolutionary relationships between the red and arctic fox.

A centromeric satellite DNA in the European plethodontid salamanders (Amphibia, Urodela)

Genome ◽  
1991 ◽  
Vol 34 (6) ◽  
pp. 1007-1012 ◽  
Author(s):  
Renata Batistoni ◽  
Irma Nardi ◽  
Lorena Rebecchi ◽  
Maria Nardone ◽  
Anna Demartis
Keyword(s):  
Satellite Dna ◽  
Centromeric Heterochromatin ◽  
Chromosomal Distribution ◽  
Base Pairs ◽  
Centromeric Satellite ◽  
Plethodontid Salamander ◽  
Plethodontid Salamanders

A highly repeated satellite DNA (Hy500) located in the centromeric heterochromatin of the European plethodontid salamander Speleomantes (formerly Hydromantes) was studied. The Hy500 family represents about 1% of the Speleomantes supramontis genome and has a major repeating unit of about 500 base pairs, which may have evolved from the progressive amplification of shorter sequences. This centromeric satellite is conserved in all the Speleomantes species, which nevertheless show distinct patterns of chromosomal distribution, which are of relevance as to their phylogenetic relationships.Key words: satellite DNA, amphibian chromosomes.

scholarly journals Distinct Regulation of the Expression of Satellite DNAs in the Beetle Tribolium castaneum

2020 ◽  
Vol 22 (1) ◽  
pp. 296
Author(s):  
Antonio Sermek ◽  
Isidoro Feliciello ◽  
Đurđica Ugarković
Keyword(s):  
Heat Stress ◽  
Tribolium Castaneum ◽  
Satellite Dna ◽  
Centromeric Heterochromatin ◽  
Satellite Dnas ◽  
Major Satellite ◽  
Satellite Repeats ◽  
Satellite Rnas ◽  
H3k9me3 Level ◽  
A Minor

In the flour beetle, Tribolium castaneum (peri)centromeric heterochromatin is mainly composed of a major satellite DNA TCAST1 interspersed with minor satellites. With the exception of heterochromatin, clustered satellite repeats are found dispersed within euchromatin. In order to uncover a possible satellite DNA function within the beetle genome, we analysed the expression of the major TCAST1 and a minor TCAST2 satellite during the development and upon heat stress. The results reveal that TCAST1 transcription was strongly induced at specific embryonic stages and upon heat stress, while TCAST2 transcription is stable during both processes. TCAST1 transcripts are processed preferentially into piRNAs during embryogenesis and into siRNAs during later development, contrary to TCAST2 transcripts, which are processed exclusively into piRNAs. In addition, increased TCAST1 expression upon heat stress is accompanied by the enrichment of the silent histone mark H3K9me3 on the major satellite, while the H3K9me3 level at TCAST2 remains unchanged. The transcription of the two satellites is proposed to be affected by the chromatin state: heterochromatin and euchromatin, which are assumed to be the prevalent sources of TCAST1 and TCAST2 transcripts, respectively. In addition, distinct regulation of the expression might be related to diverse roles that major and minor satellite RNAs play during the development and stress response.

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