Cytogenetic evidence of nucleolar dominance in allotetraploid species of Brachypodium.

@article{Idziak2008CytogeneticEO,
  title={Cytogenetic evidence of nucleolar dominance in allotetraploid species of Brachypodium.},
  author={Dominika Idziak and Robert Hasterok},
  journal={Genome},
  year={2008},
  volume={51 5},
  pages={
          387-91
        },
  url={https://api.semanticscholar.org/CorpusID:6964341}
}
The occurrence of nucleolar dominance in the allotetraploid (2n = 4x = 30) species of Brachypodium is demonstrated for the first time.
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30 Citations
Background Citations
11
Methods Citations
2
Results Citations
1

30 Citations

The fate of 35S rRNA genes in the allotetraploid grass Brachypodium hybridum

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Cytomolecular Analysis of Ribosomal DNA Evolution in a Natural Allotetraploid Brachypodium hybridum and Its Putative Ancestors—Dissecting Complex Repetitive Structure of Intergenic Spacers

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The genus Brachypodium has become the target of extensive cytomolecular studies since one of its representatives, B. distachyon, has been accepted as a model plant for temperate cereals and forage grasses and it was revealed that the number and chromosome distribution of CMA+ bands are in congruence only with 35S rDNA loci which gave strong FISH signals.

To Be or Not to Be Expressed: The First Evidence of a Nucleolar Dominance Tissue-Specificity in Brachypodium hybridum

The results indicate that genotype-specific loss of ND in B. hybridum occurs probably after fertilization during developmental processes, and supports the view that B. Hybridum is an attractive model to study ND in grasses.

Chromosome identification and reconstruction of evolutionary rearrangements in Brachypodium distachyon, B. stacei and B. hybridum

Comparative chromosome barcoding reveals rearrangements responsible for the diverse organization of Bd and Bs genomes and provides new data regarding karyotype evolution since the split of the two diploids.

Structural characterization of Brachypodium genome and its syntenic relationship with rice and wheat

The Brachypodium genome will be useful for ordering wheat ESTs within the deletion bins and developing specific markers at targeted regions in the wheat genome.

Recreating Stable Brachypodium hybridum Allotetraploids by Uniting the Divergent Genomes of B. distachyon and B. stacei

The successful creation of synthetic B. hybridum allotetraploids offers the possibility to study changes in genome structure and regulation at the earliest stages of allopolyploid formation in comparison with the parental species and natural B. hybridsum at the phenotypic, cytogenetic and genomic levels.

The Nuclear 35S rDNA World in Plant Systematics and Evolution: A Primer of Cautions and Common Misconceptions in Cytogenetic Studies

The main technical and conceptual limitations of these rDNA markers obtained by cytological and karyological experimental work are discussed in order to clarify biological and evolutionary inferences postulated in a systematic and phylogenetic context.

Nucleolar activity and physical location of ribosomal DNA loci in Vitis vinifera L. by silver staining and sequential FISH

A DNA Barcoding Method to Discriminate between the Model Plant Brachypodium distachyon and Its Close Relatives B. stacei and B. hybridum (Poaceae)

The authors' data provide an unbiased and effective barcode to differentiate these three closely-related species from one another and overcomes the taxonomic uncertainty generated from methods based on morphology or flow cytometry identifications that have resulted in some misclassifications of the model plant and its allies.

41 References

Nucleolar dominance does not occur in root tip cells of allotetraploid Brassica species.

The number of active rDNA loci of the allotetraploid species is equal to the number of AgNORs in their diploid ancestors, indicating the absence of nucleolar dominance in amphidiploid Brassica species, at least in root meristematic cells.

Organization, differential expression and methylation of rDNA in artificial Solanum allopolyploids

It is demonstrated that there is possible correlation between transcriptional dominance and number of conservative elements downstream of the transcription start in the Solanum rDNA and developmental modulation of ND.

Alignment of the Genomes of Brachypodium distachyon and Temperate Cereals and Grasses Using Bacterial Artificial Chromosome Landing With Fluorescence in Situ Hybridization

A BAC library has been constructed for the two diploid genotypes, ABR1 and ABR5, confirming the conservation of genome synteny and proving that B. distachyon has utility as a temperate grass model species alternative to rice.

BAC 'landing' on chromosomes of Brachypodium distachyon for comparative genome alignment

A BAC landing protocol that has been developed specifically for the weedy grass species Brachypodium distachyon, which has been adopted recently by the scientific community as an alternative model for the temperate cereals and grasses.

Transcriptional analysis of nucleolar dominance in polyploid plants: biased expression/silencing of progenitor rRNA genes is developmentally regulated in Brassica.

In Brassica napus, rRNA genes silenced in vegetative tissues were found to be expressed in all floral organs, arguing against the hypothesis that passage through meiosis is needed to reactivate suppressed genes.

The nucleolus organizer region of maize (Zea mays L.): Chromosomal site of DNA complementary to ribosomal RNA

A maize genetic marker strain was found to carry a cytologically-visible “duplication” of the nucleolar organizer region (NOR), and the chromosomal site of DNA complementary to rRNA was shown to be localized in the NOR, the first report on the localization of rDNA cistrons in theNOR of plants.

Mechanisms of nucleolar dominance in animals and plants

The purpose of this review is to briefly summarize the evidence for these two molecular mechanisms and then to examine each of the known types of nucleolar dominance to assess how well the proposed mechanisms can account for each case.

Brachypodium distachyon. A new model system for functional genomics in grasses.

A new model for grass functional genomics is described based on Brachypodium distachyon, which in the evolution of the Pooideae diverged just prior to the clade of "core pooid" genera that contain…

Nucleolar dominance: uniparental gene silencing on a multi-megabase scale in genetic hybrids

A historical perspective of nucleolar dominance research is provided, the most popular hypotheses and their shortcomings are explored, and some speculations concerning alternative hypotheses to be considered are offered.

Postembryonic Establishment of Megabase-Scale Gene Silencing in Nucleolar Dominance

It is shown that nucleolar dominance is not apparent in seedling cotyledons formed during embryogenesis but becomes progressively established during early postembryonic development in tissues derived from both the shoot and root apical meristems.