Abundance of Ribosomal RNA Gene Copies Maintains Genome Integrity

@article{Ide2010AbundanceOR,
  title={Abundance of Ribosomal RNA Gene Copies Maintains Genome Integrity},
  author={Satoru Ide and Takaaki Miyazaki and Hisaji Maki and Takehiko Kobayashi},
  journal={Science},
  year={2010},
  volume={327},
  pages={693 - 696}
}
Protective Abundance Massively repeated sequences are generally dangerous to genomes because they promote recombination and, potentially, genome instability. Eukaryotic ribosomal RNA genes (rDNA), which are highly transcribed, are organized into large arrays of repeats and have a system that actively maintains these large arrays. In getting to the bottom of this apparent contradiction, Ide et al. (p. 693) found that reducing the number of rDNA repeats in yeast resulted in a marked sensitivity… 

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Evidence uncovering mechanisms of regulation of instability and copy number variation at the rDNA and their role in adaptation to the environment is reviewed, which could serve to understand the basic principles governing the behavior of other tandem repeats and their roles in shaping the genome.

DNA replication stress restricts ribosomal DNA copy number

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A new aspect of the rRNA gene repeat (called rDNA) is introduced as a center of maintenance of genome integrity and its contribution to evolution is discussed.

Genome instability: The more, the merrier

  • R. David
  • Biology
    Nature Reviews Molecular Cell Biology
  • 2010
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Rtt109 Prevents Hyper-Amplification of Ribosomal RNA Genes through Histone Modification in Budding Yeast

The results support the idea that tandem DNA arrays are produced and incorporated through rolling-circle-type replication, and propose that, in the rtt109 mutant, rDNA hyper-amplification is caused by uncontrolled rolling- circle- type replication.

Genome Instability of Repetitive Sequence: Lesson from the Ribosomal RNA Gene Repeat

This review will introduce the unique mechanisms by which the rDNA repetitive region and its physiological functions are maintained.

Rejuvenation of ribosomal RNA gene repeats at the nuclear pore

The possible contribution of nuclear pores to the asymmetric distribution of damaged rDNA between mother and daughter cells as well as its possible impact on aging/rejuvenation are proposed.

Ribosomal RNA gene repeats associate with the nuclear pore complex for maintenance after DNA damage

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Gene dosage compensation of rRNA transcript levels in Arabidopsis thaliana lines with reduced ribosomal gene copy number

Gene dosage compensation of rRNA transcript levels was associated with reduction of silencing histone marks at rDNA loci and altered Nucleolar Organiser Region 2 organization, and overall genome integrity of LCN lines appears unaffected, a chromosome segmental duplication occurred in one of the lines.
...

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