Data_Sheet_1_The Role of rDNA Clusters in Global Epigenetic Gene Regulation.PDF

The regulation of gene expression has been studied for decades, but the underlying mechanisms are still not fully understood. As well as local and distant regulation, there are specific mechanisms of regulation during development and physiological modulation of gene activity in differentiated cells. Current research strongly supports a role for the 3D chromosomal structure in the regulation of gene expression. However, it is not known whether the genome structure reflects the formation of active or repressed chromosomal domains or if these structures play a primary role in the regulation of gene expression. During early development, heterochromatinization of ribosomal DNA (rDNA) is coupled with silencing or activation of the expression of different sets of genes. Although the mechanisms behind this type of regulation are not known, rDNA clusters shape frequent inter-chromosomal contacts with a large group of genes controlling development. This review aims to shed light on the involvement of clusters of ribosomal genes in the global regulation of gene expression. We also discuss the possible role of RNA-mediated and phase-separation mechanisms in the global regulation of gene expression by nucleoli.

基因表达的调控研究已持续数十年，但其潜在机制仍未完全明了。除了局部和远距离调控之外，在发育过程中以及分化细胞中基因活动的生理性调节亦存在特定的调控机制。当前的研究强烈支持三维染色体结构在基因表达调控中的角色。然而，尚不清楚基因组结构是否反映了活性或抑制性染色质域的形成，抑或这些结构在基因表达调控中发挥主导作用。在早期发育阶段，核糖体DNA（rDNA）的异染色质化与不同基因组的沉默或激活表达相耦合。尽管此类调控背后的机制尚不明确，但rDNA簇与一组调控发育的基因频繁形成染色体间接触。本综述旨在揭示核糖体基因簇在全球基因表达调控中的作用。同时，我们也探讨了RNA介导的和相分离机制在全球基因表达调控中核仁的可能作用。