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Mechanisms of rDNA Copy Number Maintenance.

ABSTRACT: rDNA, the genes encoding the RNA components of ribosomes (rRNA), are highly repetitive in all eukaryotic genomes, containing 100s to 1000s of copies, to meet the demand for ribosome biogenesis. rDNA genes are arranged in large stretches of tandem repeats, forming loci that are highly susceptible to copy loss due to their repetitiveness and active transcription throughout the cell cycle. Despite this inherent instability, rDNA copy number is generally maintained within a particular range in each species, pointing to the presence of mechanisms that maintain rDNA copy number in a homeostatic range. In this review, we summarize the current understanding of these maintenance mechanisms and how they sustain rDNA copy number throughout populations.

SUBMITTER: Nelson JO

PROVIDER: S-EPMC6744303 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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Mechanisms of rDNA Copy Number Maintenance.

Nelson Jonathan O JO Watase George J GJ Warsinger-Pepe Natalie N Yamashita Yukiko M YM

Trends in genetics : TIG 20190805 10

rDNA, the genes encoding the RNA components of ribosomes (rRNA), are highly repetitive in all eukaryotic genomes, containing 100s to 1000s of copies, to meet the demand for ribosome biogenesis. rDNA genes are arranged in large stretches of tandem repeats, forming loci that are highly susceptible to copy loss due to their repetitiveness and active transcription throughout the cell cycle. Despite this inherent instability, rDNA copy number is generally maintained within a particular range in each ...[more]

PMID: 31395390

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