Wang Jayson, Shiels Carol, Sasieni Peter, Wu Pei Jun, Islam Suhail A, Freemont Paul S, Sheer Denise
Human Cytogenetics Laboratory, Cancer Research UK, London Research Institute, 44 Lincoln's Inn Fields, London WC2A 3PX, England, UK.
J Cell Biol. 2004 Feb 16;164(4):515-26. doi: 10.1083/jcb.200305142.
The promyelocytic leukemia (PML) protein is aggregated into nuclear bodies that are associated with diverse nuclear processes. Here, we report that the distance between a locus and its nearest PML body correlates with the transcriptional activity and gene density around the locus. Genes on the active X chromosome are more significantly associated with PML bodies than their silenced homologues on the inactive X chromosome. We also found that a histone-encoding gene cluster, which is transcribed only in S-phase, is more strongly associated with PML bodies in S-phase than in G0/G1 phase of the cell cycle. However, visualization of specific RNA transcripts for several genes showed that PML bodies were not themselves sites of transcription for these genes. Furthermore, knock-down of PML bodies by RNA interference did not preferentially change the expression of genes closely associated with PML bodies. We propose that PML bodies form in nuclear compartments of high transcriptional activity, but they do not directly regulate transcription of genes in these compartments.
早幼粒细胞白血病（PML）蛋白聚集形成与多种核过程相关的核体。在此，我们报告一个基因座与其最近的PML体之间的距离与该基因座周围的转录活性和基因密度相关。活性X染色体上的基因与其在失活X染色体上沉默的同源基因相比，与PML体的关联更为显著。我们还发现，仅在S期转录的组蛋白编码基因簇，在细胞周期的S期比在G0/G1期与PML体的关联更强。然而，对几个基因的特定RNA转录本的可视化显示，PML体本身并非这些基因的转录位点。此外，通过RNA干扰敲低PML体并不会优先改变与PML体紧密相关的基因的表达。我们提出，PML体在转录活性高的核区室中形成，但它们并不直接调节这些区室中基因的转录。
