Nuclear Pore Complex (NPC) Disassembly

Nuclear envelope breakdown in mitosis involves permeabilization of the nuclear envelope through disassembly of the nuclear pore complex (NPC) (reviewed by Guttinger et al. 2009). Nucleoporin NUP98, located at both the cytoplasmic and the nucleoplasmic side of the NPC (Griffis et al. 2003), and involved in the formation of the transport barrier through its FG (phenylalanine glycine) repeats that protrude into the central cavity of the NPC (Hulsmann et al. 2012), is probably the first nucleoporin that dissociates from the NPC at the start of mitotic NPC disassembly (Dultz et al. 2008). NUP98 dissociation is triggered by phosphorylation. Phosphorylation of NUP98 by CDK1 and NIMA family kinases NEK6 and/or NEK7 is needed for NUP98 dissociation from the NPC (Laurell et al. 2011). While the phosphorylation of NUP98 by CDK1 and NEK6/7 is likely to occur simultaneously, CDK1 and NEK6/7-mediated phosphorylations are shown as separate events, for clarity purposes.

有丝分裂过程中，核被膜破裂涉及通过核孔复合体（NPC）的解聚来使核被膜通透化（Guttinger 等人，2009年综述）。位于NPC的胞质侧和核质侧的核孔蛋白NUP98（Griffis 等人，2003年研究），通过其突出至NPC中央腔的苯丙氨酸甘氨酸（FG）重复序列参与形成运输屏障的构建（Hulsmann 等人，2012年研究），可能是首先在有丝分裂NPC解聚开始时从NPC解离的核孔蛋白（Dultz 等人，2008年研究）。NUP98的解离由磷酸化触发。NUP98由CDK1和NIMA家族激酶NEK6和/或NEK7磷酸化对于NUP98从NPC解离是必需的（Laurell 等人，2011年研究）。尽管CDK1和NEK6/7对NUP98的磷酸化可能同时发生，但为了清晰起见，CDK1和NEK6/7介导的磷酸化被展示为单独的事件。