Cell cycle-dependent association of PML bodies with sites of active transcription in nuclei of mammalian cells
Cell cycle-dependent association of PML bodies with sites of active transcription in nuclei of mammalian cells
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DOI：
10.1016/s1047-8477(02)00571-3
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发表时间：
2002-10-01
影响因子：
3
通讯作者：
Hemmerich, P
中科院分区：
文献类型：
--
作者：
Kiesslich, A;von Mikecz, A;Hemmerich, P
早幼粒细胞白血病（PML）的核体构成一类核内结构域，可能直接参与特定基因的表达。在这里，我们分析了PML机构和转录活性的网站之间的空间关系，间接免疫荧光和共聚焦显微镜在细胞周期。在非同步化的哺乳动物细胞中，约30%的PML小体与转录位点空间相关。这些位点含有过度磷酸化的RNA聚合酶11，表明与PML体紧密相关的活性mRNA转录。在细胞周期的G1期，超过70%的PML小体含有活跃的转录灶。当细胞暴露于干扰素-γ时，也观察到PML小体和活性转录位点之间类似的高度共定位（约80%）。我们还表明，低磷酸化形式的RNA聚合酶11和转录辅激活因子CBP共定位在PML机构主要在G1。我们的观察结果表明，PML机构可能被招募到核网站的诱导或上调mRNA转录，它可以作为一个支架的特定基因的表达所涉及的因素。(C)2002 Elsevier Science（美国）。All rights reserved.
Promyelocytic leukemia (PML) nuclear bodies constitute one class of intranuclear domains that may be directly involved in the expression of specific genes. Here we have analyzed the spatial relationship between PML bodies and sites of transcriptional activity by indirect immunofluorescence and confocal microscopy during the cell cycle. In unsynchronized mammalian cells approx 30% of PML bodies are spatially associated with transcription sites. These sites contain hyperphosphorylated RNA polymerase 11, indicating active mRNA transcription tightly associated with the PML body. In G1 phase of the cell cycle more than 70% of PML bodies contain active transcription foci. A similarly high degree of colocalization (approx 80%) between PML bodies and sites of active transcription was also observed when the cells were exposed to interferon-gamma. We also show that the hypophosphorylated form of RNA polymerase 11 and the transcriptional coactivator CBP colocalize within PML bodies predominantly in G1. Our observations suggest that PML bodies may be recruited to nuclear sites of induced or up-regulated mRNA transcription where it may serve as a scaffold for factors involved in expression of specific genes. (C) 2002 Elsevier Science (USA). All rights reserved.