Verschure Pernette J, Van Der Kraan Ineke, Enserink Jorrit M, Moné Martijn J, Manders Erik M M, Van Driel Roel
Swammerdam Institute for Life Sciences, BioCentrum Amsterdam, University of Amsterdam, Amsterdam, The Netherlands.
J Histochem Cytochem. 2002 Oct;50(10):1303-12. doi: 10.1177/002215540205001003.
Compartmentalization of the interphase nucleus is an important element in the regulation of gene expression. Here we investigated the functional organization of the interphase nucleus of HeLa cells and primary human fibroblasts. The spatial distribution of proteins involved in transcription (TFIIH and RNA polymerase II) and RNA processing and packaging (hnRNP-U) were analyzed in relation to chromosome territories and large-scale chromatin organization. We present evidence that these proteins are present predominantly in the interchromatin space, inside and between chromosome territories, and are largely excluded by domains of condensed chromatin. We show that they are present throughout the active and inactive X-chromosome territories in primary female fibroblasts, indicating that these proteins can freely diffuse throughout the interchromatin compartment in the interphase nucleus. Furthermore, we established that the in vivo spatial distribution of condensed chromatin in the interphase nucleus does not depend on ongoing transcription. Our data support a conceptually simple model for the functional organization of interphase nuclei.
间期细胞核的区室化是基因表达调控中的一个重要因素。在此，我们研究了HeLa细胞和原代人成纤维细胞间期细胞核的功能组织。分析了参与转录（TFIIH和RNA聚合酶II）以及RNA加工和包装（hnRNP-U）的蛋白质相对于染色体区域和大规模染色质组织的空间分布。我们提供的证据表明，这些蛋白质主要存在于染色质间空间，即染色体区域内部和之间，并且在很大程度上被浓缩染色质结构域排除在外。我们表明，它们存在于原代雌性成纤维细胞的活跃和不活跃X染色体区域中，这表明这些蛋白质可以在间期细胞核的染色质间区室中自由扩散。此外，我们确定了间期细胞核中浓缩染色质的体内空间分布不依赖于正在进行的转录。我们的数据支持了一个概念上简单的间期细胞核功能组织模型。
