Dvořáčková Martina, Fojtová Miloslava, Fajkus Jiří
Mendel Centre for Plant Genomics and Proteomics, Central European Institute of Technology, Kamenice 5, 62500, Brno, Czech Republic.
Faculty of Science, Masaryk University, Kamenice 5, 62500, Brno, Czech Republic.
Plant J. 2015 Jul;83(1):18-37. doi: 10.1111/tpj.12822. Epub 2015 May 4.
Telomeres and genes encoding 45S ribosomal RNA (rDNA) are frequently located adjacent to each other on eukaryotic chromosomes. Although their primary roles are different, they show striking similarities with respect to their features and additional functions. Both genome domains have remarkably dynamic chromatin structures. Both are hypersensitive to dysfunctional histone chaperones, responding at the genomic and epigenomic levels. Both generate non-coding transcripts that, in addition to their epigenetic roles, may induce gross chromosomal rearrangements. Both give rise to chromosomal fragile sites, as their replication is intrinsically problematic. However, at the same time, both are essential for maintenance of genomic stability and integrity. Here we discuss the structural and functional inter-connectivity of telomeres and rDNA, with a focus on recent results obtained in plants.
端粒和编码45S核糖体RNA（rDNA）的基因在真核染色体上常常彼此相邻。尽管它们的主要作用不同，但在特征和附加功能方面却表现出惊人的相似性。这两个基因组区域都具有显著动态的染色质结构。二者对功能失调的组蛋白伴侣都高度敏感，在基因组和表观基因组水平上均有响应。二者都会产生非编码转录本，这些转录本除了具有表观遗传作用外，还可能诱导大规模染色体重排。二者都会产生染色体脆弱位点，因为它们的复制本质上存在问题。然而，与此同时，二者对于维持基因组稳定性和完整性都是必不可少的。在这里，我们讨论端粒和rDNA的结构与功能的相互联系，重点关注植物方面的最新研究结果。
