Institute of Biology and Medical Genetics, First Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czech Republic.
Histochem Cell Biol. 2019 Oct;152(4):271-280. doi: 10.1007/s00418-019-01804-5. Epub 2019 Jul 25.
In human cells, the intergenic spacers (IGS), which separate ribosomal genes, are complex approximately 30 kb-long loci. Recent studies indicate that all, or almost all, parts of IGS may be transcribed, and that at least some of them are involved in the regulation of the ribosomal DNA (rDNA) transcription, maintenance of the nucleolar architecture, and response of the cell nucleus to stress. However, since each cell contains hundreds not quite identical copies of IGS, the structure and functions of this locus remain poorly understood, and the dynamics of its products has not been specially studied. In this work, we used quantitative PCR to measure the expression levels of various rDNA regions at different times after inhibition of the transcription by Actinomycin D applied in high doses. This approach allowed us to measure real or extrapolated half-life times of some IGS loci. Our study reveals characteristic dynamic patterns suggestive of various pathways of RNA utilization and decay.
在人类细胞中，间隔基因间区（IGS）分离核糖体基因，其大约 30kb 长的基因座十分复杂。最近的研究表明，IGS 的所有或几乎所有部分都可能被转录，并且至少其中一些部分参与了核糖体 DNA（rDNA）转录的调控、核仁结构的维持以及细胞核对应激的反应。然而，由于每个细胞都包含数百个不完全相同的 IGS 拷贝，因此该基因座的结构和功能仍未被充分了解，其产物的动态也尚未被专门研究。在这项工作中，我们使用定量 PCR 在高剂量放线菌素 D 抑制转录后不同时间测量各种 rDNA 区域的表达水平。这种方法使我们能够测量一些 IGS 基因座的真实或推断的半衰期。我们的研究揭示了特征性的动态模式，表明了各种 RNA 利用和降解途径。
