Kahn, Samuel2017-05-102017-05-102004Dahl, K.N., S.M Kahn, K.L. Wilson, and Dennis E. Discher. 2004. "The Nuclear Envelope Lamina Network Has Elasticity and a Compressibility Limit Suggestive of a Molecular Shock Absorber." Journal of Cell Science, 117: 4779-4786. doi: 10.1242/jcs.01357https://hdl.handle.net/1805/12492Author Posting © Journal of Cell Science, 2004. This article is posted here by permission of Journal of Cell Science for personal use, not for redistribution. The article was published in the Journal of Cell Science, Volume 117, 2004, http://dx.doi.org/10.1242/jcs.01357Mechanical properties of the nuclear envelope have implications for cell and nuclear architecture as well as gene regulation. Using isolated Xenopus oocyte nuclei, we have established swelling conditions that separate the intact nuclear envelope (membranes, pore complexes and underlying lamin filament network) from nucleoplasm and the majority of chromatin. Swelling proves reversible with addition of high molecular mass dextrans. Micropipette aspiration of swollen and unswollen nuclear envelopes is also reversible and yields a network elastic modulus, unaffected by nucleoplasm, that averages 25 mN/m. Compared to plasma membranes of cells, the nuclear envelope is much stiffer and more resilient. Our results suggest that the nuclear lamina forms a compressed network shell of interconnected rods that is extensible but limited in compressibility from the native state, thus acting as a ‘molecular shock absorber’. In light of the conservation of B-type lamins in metazoan evolution, the mechanical properties determined in this investigation suggest physical mechanisms by which mutated lamins can either destabilize nuclear architecture or influence nuclear responses to mechanical signals in Emery-Dreifuss muscular dystrophy, cardiomyopathy, progeria syndromes (premature ‘aging’) and other laminopathies.en-USAttribution-NonCommercial-NoDerivs 3.0 United Statesnuclear envelopeelasticitynuclear laminaArticle10.1242/jcs.01357