Chromosomal distribution of a new centromeric Ty3-gypsy retrotransposon sequence in Dasypyrum and related Triticeae species

The TaiI family sequences are classified as tandem repetitive DNA sequences present in the genome of tribe Triticeae, and are localized in the centromeric regions of common wheat, but in the subtelomeric heterochromatic regions of Leymus racemosus and related species. In this study, we investigated the chromosomal distribution of TaiI family sequences in other Triticeae species. The results demonstrated a centromeric localization in genera Triticum and Aegilops and subtelomeric localization in other genera, thus showing a genus-dependent localization of TaiI family sequences in one or the other region. The copy numbers of TaiI family sequences in species in the same genus varied greatly, whether in the centromeric or subtelomeric regions (depending on genus). We also examined the evolution of TaiI family sequences during polyploidization of hexaploid common wheat. A comparison of chromosomal locations of the major TaiI family signals in common wheat and in its ancestral species suggested that the centromeric TaiI family sequences in common wheat were inherited from its ancestors with little modification, whereas a mixed origin for the B genome of common wheat was indicated.Key words: TaiI family, tandem repeat, centromere, subtelomere, Triticeae.

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The in vivo distribution and dynamics of DNA topoisomerase II in Drosophila embryonic nuclei and chromosomes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100146217 ◽

1993 ◽

Vol 51 ◽

pp. 74-75

Author(s):

Jason R. Swedlow ◽

Neil Osheroff ◽

Tim Karr ◽

John W. Sedat ◽

David A. Agard

Keyword(s):

Topoisomerase Ii ◽

Biochemical Characterization ◽

Developmental Cycle ◽

Dna Topoisomerase Ii ◽

Chromosomal Distribution ◽

Dna Topoisomerase ◽

Ideal System ◽

Dnase Treatment

DNA topoisomerase II is an ATP-dependent double-stranded DNA strand-passing enzyme that is necessary for full condensation of chromosomes and for complete segregation of sister chromatids at mitosis in vivo and in vitro. Biochemical characterization of chromosomes or nuclei after extraction with high-salt or detergents and DNAse treatment showed that topoisomerase II was a major component of this remnant, termed the chromosome scaffold. The scaffold has been hypothesized to be the structural backbone of the chromosome, so the localization of topoisomerase II to die scaffold suggested that the enzyme might play a structural role in the chromosome. However, topoisomerase II has not been studied in nuclei or chromosomes in vivo. We have monitored the chromosomal distribution of topoisomerase II in vivo during mitosis in the Drosophila embryo. This embryo forms a multi-nucleated syncytial blastoderm early in its developmental cycle. During this time, the embryonic nuclei synchronously progress through 13 mitotic cycles, so this is an ideal system to follow nuclear and chromosomal dynamics.

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Evolutionary dynamics and chromosomal distribution of repetitive sequences on chromosomes of Aegilops speltoides revealed by genomic in situ hybridization

Heredity ◽

10.1046/j.1365-2540.2001.00891.x ◽

2001 ◽

Vol 86 (6) ◽

pp. 738-742 ◽

Cited By ~ 7

Author(s):

Alexander Belyayev ◽

Olga Raskina ◽

Eviatar Nevo

Keyword(s):

In Situ Hybridization ◽

Evolutionary Dynamics ◽

Repetitive Sequences ◽

Genomic In Situ Hybridization ◽

Aegilops Speltoides ◽

Chromosomal Distribution

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The correlations between chromosomal distribution of early pregnancy loss and the existence of an embryo as well as the postmortem embryonic pole length after IVF-ET

10.26226/morressier.573c1511d462b80296c9823b ◽

2016 ◽

Author(s):

Yan Ouyang

Keyword(s):

Early Pregnancy ◽

Pregnancy Loss ◽

Early Pregnancy Loss ◽

Chromosomal Distribution ◽

Ivf Et

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Analysis of Inter-Chromosomal Distribution of Disease-Related Genes in Human Genome

Current Protein and Peptide Science ◽

10.2174/1389203721666200426233158 ◽

2020 ◽

Vol 21 (11) ◽

pp. 1068-1077

Author(s):

Xiaochao Sun ◽

Bin Yang ◽

Qunye Zhang

Keyword(s):

Spatial Distribution ◽

Model Organisms ◽

Nucleotide Polymorphisms ◽

Chromosomal Distribution ◽

Single Nucleotide ◽

Protein Coding ◽

Single Chromosome ◽

Deletion Mutations ◽

Protein Coding Genes ◽

Disease Related Genes

: Many studies have shown that the spatial distribution of genes within a single chromosome exhibits distinct patterns. However, little is known about the characteristics of inter-chromosomal distribution of genes (including protein-coding genes, processed transcripts and pseudogenes) in different genomes. In this study, we explored these issues using the available genomic data of both human and model organisms. Moreover, we also analyzed the distribution pattern of protein-coding genes that have been associated with 14 common diseases and the insert/deletion mutations and single nucleotide polymorphisms detected by whole genome sequencing in an acute promyelocyte leukemia patient. We obtained the following novel findings. Firstly, inter-chromosomal distribution of genes displays a nonstochastic pattern and the gene densities in different chromosomes are heterogeneous. This kind of heterogeneity is observed in genomes of both lower and higher species. Secondly, protein-coding genes involved in certain biological processes tend to be enriched in one or a few chromosomes. Our findings have added new insights into our understanding of the spatial distribution of genome and disease- related genes across chromosomes. These results could be useful in improving the efficiency of disease-associated gene screening studies by targeting specific chromosomes.

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Interaction Between Mutations in the suppressor of Hairy wing and modifier of mdg4 Genes of Drosophila melunogaster Affecting the Phenotype of gypsy-Induced Mutations

Genetics ◽

10.1093/genetics/142.2.425 ◽

1996 ◽

Vol 142 (2) ◽

pp. 425-436 ◽

Cited By ~ 5

Author(s):

Pavel Georgiev ◽

Marina Kozycina

Keyword(s):

Mutagenic Effect ◽

Induced Mutations ◽

Binding Region ◽

Direct Inhibition ◽

Amino Terminal ◽

Acidic Domain ◽

Complete Inactivation ◽

Insulation Effect ◽

Gypsy Retrotransposon ◽

Carboxy Terminal

Abstract The suppressor of Hairy-wing [su(Hw)] protein mediates the mutagenic effect of the gypsy retrotransposon by repressing the function of transcriptional enhancers located distally from the promoter with respect to the position of the su(Hw)-binding region. Mutations in a second gene, modifier of mdg4, also affect the gypsy-induced phenotype. Two major effects of the mod(mdg4)lul mutation can be distinguished: the interference with insulation by the su(Hw)-binding region and direct inhibition of gene expression that is not dependent on the su(Hw)-binding region position. The mod(mdg4)lul mutation partially suppresses ct6, scD1 and Hw1 mutations, possibly by interfering with the insulation effect of the su(Hw)-binding region. An example of the second effect of mod(mdg4)lul is a complete inactivation of yellow expression in combination with the y 2 allele. Phenotypic analyses of flies with combinations of mod(mdg4)lul and different su(Hw) mutations, or with constructions carrying deletions of the acidic domains of the su(Hw) protein, suggest that the carboxy-terminal acidic domain is important for direct inhibition of yellow transcription in bristles, while the amino-terminal acidic domain is more essential for insulation.

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Comparative FISH analysis of Senna tora tandem repeats revealed insights into the chromosome dynamics in Senna

Genes & Genomics ◽

10.1007/s13258-021-01051-w ◽

2021 ◽

Vol 43 (3) ◽

pp. 237-249 ◽

Cited By ~ 2

Author(s):

Thanh Dat Ta ◽

Nomar Espinosa Waminal ◽

Thi Hong Nguyen ◽

Remnyl Joyce Pellerin ◽

Hyun Hee Kim

Keyword(s):

Tandem Repeats ◽

Chromosomal Rearrangements ◽

Organizer Region ◽

Nucleolar Organizer Region ◽

Nucleolar Organizer ◽

Pericentromeric Region ◽

Its2 Sequence ◽

Fish Analysis ◽

Chromosomal Distribution ◽

Chromosome Dynamics

Abstract Background DNA tandem repeats (TRs) are often abundant and occupy discrete regions in eukaryotic genomes. These TRs often cause or generate chromosomal rearrangements, which, in turn, drive chromosome evolution and speciation. Tracing the chromosomal distribution of TRs could therefore provide insights into the chromosome dynamics and speciation among closely related taxa. The basic chromosome number in the genus Senna is 2n = 28, but dysploid species like Senna tora have also been observed. Objective To understand the dynamics of these TRs and their impact on S. tora dysploidization. Methods We performed a comparative fluorescence in situ hybridization (FISH) analysis among nine closely related Senna species and compared the chromosomal distribution of these repeats from a cytotaxonomic perspective by using the ITS1-5.8S-ITS2 sequence to infer phylogenetic relationships. Results Of the nine S. tora TRs, two did not show any FISH signal whereas seven TRs showed similar and contrasting patterns to other Senna species. StoTR01_86, which was localized in the pericentromeric regions in all S. tora, but not at the nucleolar organizer region (NOR) site, was colocalized at the NOR site in all species except in S. siamea. StoTR02_7_tel was mostly localized at chromosome termini, but some species had an interstitial telomeric repeat in a few chromosomes. StoTR05_180 was distributed in the subtelomeric region in most species and was highly amplified in the pericentromeric region in some species. StoTR06_159 was either absent or colocalized in the NOR site in some species, and StoIGS_463, which was localized at the NOR site in S. tora, was either absent or localized at the subtelomeric or pericentromeric regions in other species. Conclusions These data suggest that TRs play important roles in S. tora dysploidy and suggest the involvement of 45S rDNA intergenic spacers in “carrying” repeats during genome reshuffling.

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