Genes encoding ribosomal RNA (rDNA) are essential for cell survival and are particularly sensitive to factors leading to genomic instability. Their repetitive character makes them prone to inappropriate recombinational events arising from collision of transcriptional and replication machineries, resulting in unstable rDNA copy numbers. In this review, we summarize current knowledge on the structure and organization of rDNA, its role in sensing changes in the genome, and its linkage to aging. We also review recent findings on the main factors involved in chromatin assembly and DNA repair in the maintenance of rDNA stability in the model plants Arabidopsis thaliana and the moss Physcomitrella patens, providing a view across the plant evolutionary tree.

• Keywords
• CAF-1, RAD51, RTEL1, genome stability, rDNA organization, rRNA genes, ribosome,
• MeSH
• Arabidopsis genetics   MeSH
• DNA, Plant genetics   MeSH
• Transcription, Genetic MeSH
• Gene Dosage MeSH
• Humans MeSH
• Bryopsida genetics   MeSH
• Genomic Instability MeSH
• DNA Repair * MeSH
• DNA Replication MeSH
• Chromatin Assembly and Disassembly MeSH
• DNA, Ribosomal genetics   MeSH
• Aging genetics   MeSH
• Animals MeSH
• Check Tag
• Humans MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Review MeSH
• Names of Substances
• DNA, Plant MeSH
• DNA, Ribosomal MeSH