Robaszkiewicz Ewa, Idziak-Helmcke Dominika, Tkacz Magdalena A, Chrominski Kornel, Hasterok Robert
Department of Plant Anatomy and Cytology, Faculty of Biology and Environmental Protection, University of Silesia in Katowice, Katowice, Poland
Department of Plant Anatomy and Cytology, Faculty of Biology and Environmental Protection, University of Silesia in Katowice, Katowice, Poland.
J Exp Bot. 2016 Oct;67(18):5571-5583. doi: 10.1093/jxb/erw325. Epub 2016 Sep 1.
The spatial organization of chromatin within the interphase nucleus and the interactions between chromosome territories (CTs) are essential for various biological processes, such as DNA replication, transcription, and repair. However, detailed data about the CT arrangement in monocotyledonous plants are scarce. In this study, chromosome painting was used to analyse the distribution and associations of individual chromosomes in the 3-D preserved nuclei of Brachypodium distachyon root cells in order to determine the factors that may have an impact on the homologous CT arrangement. It was shown that the frequency of CT association is linked to the steric constraints imposed by the limited space within the nucleus and may depend on chromosome size and morphology as well as on the nuclear shape. Furthermore, in order to assess whether the distribution of interphase chromosomes is random or is subject to certain patterns, a comparison between the experimental data and the results of a computer simulation (ChroTeMo), which was based on a fully probabilistic distribution of the CTs, was performed. This comparison revealed that homologous chromosome arm CTs associate more often than if they were randomly arranged inside the interphase nucleus.
间期细胞核内染色质的空间组织以及染色体区域（CTs）之间的相互作用对于各种生物学过程至关重要，如DNA复制、转录和修复。然而，关于单子叶植物中CT排列的详细数据却很稀少。在本研究中，采用染色体涂染技术分析了短柄草属植物根细胞三维保存细胞核中单个染色体的分布和关联，以确定可能影响同源CT排列的因素。结果表明，CT关联频率与细胞核内有限空间所施加的空间限制有关，可能取决于染色体大小和形态以及细胞核形状。此外，为了评估间期染色体的分布是随机的还是受特定模式支配，将实验数据与基于CT完全概率分布的计算机模拟（ChroTeMo）结果进行了比较。该比较结果表明，与它们在间期细胞核内随机排列的情况相比，同源染色体臂CTs之间的关联更为频繁。
