Pedersen Ross Ta, Zhuang Yinyin, Reyes Andres V, Xu Shou-Ling, Shi Xiaoyu, Zheng Yixian
Department of Embryology, Carnegie Institution for Science; Baltimore, MD.
Department of Developmental and Cell Biology, University of California, Irvine; Irvine, CA.
bioRxiv. 2025 Jul 30:2025.07.28.667287. doi: 10.1101/2025.07.28.667287.
Intermediate filaments called lamins line the metazoan nuclear envelope and organize the nucleus and genome. Unlike actin and microtubules, purified intermediate filament proteins assemble into non-physiological structures, making it difficult to connect lamin functions to their assembly and regulation. To overcome this challenge, we reconstituted lamin assembly without nuclear assembly using interphase egg extracts that recapitulate physiological context. Mimicking nucleoplasm conditions triggers dispersed lamin assembly in egg extracts. Such ectopic lamin assembly occurs on nuclear pore complex-containing membranes, but does not recruit known nuclear lamina components, demonstrating that lamin assembly is separable from the rest of the nuclear lamina and nucleus. This assembly assay in the physiological context of cellular components opens the door to mechanistically dissecting nuclear lamina function in nuclear organization.
被称为核纤层蛋白的中间丝排列在后生动物的核膜内，对细胞核和基因组进行组织。与肌动蛋白和微管不同，纯化的中间丝蛋白会组装成非生理性结构，这使得难以将核纤层蛋白的功能与其组装和调节联系起来。为了克服这一挑战，我们利用重现生理环境的间期卵提取物，在不进行细胞核组装的情况下重建了核纤层蛋白组装。模拟核质条件会触发卵提取物中分散的核纤层蛋白组装。这种异位核纤层蛋白组装发生在含有核孔复合体的膜上，但不会招募已知的核纤层成分，这表明核纤层蛋白组装与核纤层和细胞核的其他部分是可分离的。在细胞成分的生理环境中进行的这种组装分析，为从机制上剖析核纤层在细胞核组织中的功能打开了大门。
