A dominant-negative form of POM121 binds chromatin and disrupts the two separate modes of nuclear pore assembly

• DOI: 10.1242/jcs.086660
• Publication Date: 2011-11-19T02:02:59Z
• Authors: Lihi Shaulov; Rita Gruber; Ilana Cohen; Amnon Harel
• Keywords: Nuclear pore; Nuclear membrane; Nucleoporin; Interphase; Inner membrane

Nuclear pore complexes (NPCs) are formed during two separate stages of the metazoan cell cycle. They assembled into re-forming nuclear envelope (NE) at exit from mitosis and an intact, expanding NE interphase. Here, we show that a soluble internal fragment membrane nucleoporin POM121 has dominant-negative effect on both modes assembly in cell-free reconstitution system. The binds chromatin sites distinct ELYS-Nup107-160 'seeding' prevents enclosure NPC formation. Importin-β negatively regulates binding by through conserved NLS motif is also shown to affect recruitment endogenous protein full When intact present before addition fragment, NPCs inserted but expansion inhibited. This results densely packed with no intervening patches, as visualized scanning electron microscopy. We conclude plays important role links formation biogenesis.