Department of Biology of the Cell Nucleus, Institute of Molecular Genetics CAS, v.v.i., Vídeňská 1083, 142 00, Prague, Czech Republic.
Department of Cybernetics, Faculty of Electrical Engineering, Czech Technical University in Prague, Prague, Czech Republic.
Cell Mol Life Sci. 2019 Jun;76(11):2199-2216. doi: 10.1007/s00018-019-03037-0. Epub 2019 Feb 14.
The organization of the nuclear periphery is crucial for many nuclear functions. Nuclear lamins form dense network at the nuclear periphery and play a substantial role in chromatin organization, transcription regulation and in organization of nuclear pore complexes (NPCs). Here, we show that TPR, the protein located preferentially within the nuclear baskets of NPCs, associates with lamin B1. The depletion of TPR affects the organization of lamin B1 but not lamin A/C within the nuclear lamina as shown by stimulated emission depletion microscopy. Finally, reduction of TPR affects the distribution of NPCs within the nuclear envelope and the effect can be reversed by simultaneous knock-down of lamin A/C or the overexpression of lamin B1. Our work suggests a novel role for the TPR at the nuclear periphery: the TPR contributes to the organization of the nuclear lamina and in cooperation with lamins guards the interphase assembly of nuclear pore complexes.
核周组织对于许多核功能至关重要。核纤层在核周形成致密网络,在染色质组织、转录调控和核孔复合体(NPC)的组织中发挥重要作用。在这里,我们表明,TPR,一种优先位于 NPC 核篮中的蛋白,与 lamin B1 结合。TPR 的耗竭会影响核纤层中 lamin B1 的组织,但不会影响 lamin A/C,这一点通过受激发射损耗显微镜显示。最后,TPR 的减少会影响 NPC 在核膜中的分布,而 lamin A/C 的同时敲低或 lamin B1 的过表达可以逆转这种影响。我们的工作表明 TPR 在核周具有新的作用:TPR 有助于核纤层的组织,并与 lamin 一起保护核孔复合体的有丝分裂组装。