Cibulka Jakub, Bisaccia Fabio, Radisavljević Katarina, Gudino Carrillo Ricardo M, Köhler Alwin
Max Perutz Labs, University of Vienna and Medical University of Vienna, Vienna Biocenter Campus (VBC), Dr. Bohr-Gasse 9/3, 1030 Vienna, Austria.
Sci Adv. 2022 Feb 11;8(6):eabl6863. doi: 10.1126/sciadv.abl6863.
Nuclear pore complexes (NPCs) are membrane-embedded gatekeepers of traffic between the nucleus and cytoplasm. Key features of the NPC symmetric core have been elucidated, but little is known about the NPC basket, a prominent structure with numerous roles in gene expression. Studying the basket was hampered by its instability and connection to the inner nuclear membrane (INM). Here, we reveal the assembly principle of the yeast NPC basket by reconstituting a recombinant Nup60-Mlp1-Nup2 scaffold on a synthetic membrane. Nup60 serves as the basket's flexible suspension cable, harboring an array of short linear motifs (SLiMs). These bind multivalently to the INM, the coiled-coil protein Mlp1, the FG-nucleoporin Nup2, and the NPC core. We suggest that SLiMs, embedded in disordered regions, allow the basket to adapt its structure in response to bulky cargo and changes in gene expression. Our study opens avenues for the higher-order reconstitution of basket-anchored NPC assemblies on membranes.
核孔复合体（NPCs）是细胞核与细胞质之间物质运输的膜嵌入守门者。NPC对称核心的关键特征已得到阐明，但对于NPC篮状结构却知之甚少，该结构在基因表达中具有多种重要作用。由于其不稳定性以及与内核膜（INM）的连接，对篮状结构的研究受到了阻碍。在这里，我们通过在合成膜上重构重组Nup60-Mlp1-Nup2支架，揭示了酵母NPC篮状结构的组装原理。Nup60作为篮状结构的柔性悬索，含有一系列短线性基序（SLiMs）。这些基序多价结合到INM、卷曲螺旋蛋白Mlp1、FG核孔蛋白Nup2和NPC核心上。我们认为，嵌入无序区域的SLiMs使篮状结构能够根据大分子货物和基因表达的变化调整其结构。我们的研究为在膜上进行篮状结构锚定的NPC组装的高阶重构开辟了道路。
