title: Influence of lamin A on the mechanical properties of amphibian oocyte nuclei measured by atomic force microscopy.
abstract: The nuclear lamina is part of the nuclear envelope (NE). Lamin filaments provide the nucleus with mechanical stability and are involved in many nuclear activities. The functional importance of these proteins is highlighted by mutations in lamin genes, which cause a variety of human diseases (laminopathies). Here we describe a method that allows one to quantify the contribution of lamin A protein to the mechanical properties of the NE. Lamin A is ectopically expressed in Xenopus oocytes, where it is incorporated into the NE of the oocyte nucleus, giving rise to a prominent lamina layer at the inner nuclear membrane. Nuclei are then isolated and probed by atomic force microscopy. From the resulting force curves, stiffness values are calculated and compared with those of control nuclei. Expression of lamin A significantly increases the stiffness of oocyte nuclei in a concentration-dependent manner. Since chromatin adds negligibly to nuclear mechanics in these giant nuclei, this method allows one to measure the contribution of individual NE components to nuclear mechanics.
authors.affiliation: Institute of Cell Biology, University of Bremen, Bremen, Germany.
authors.forename: Jens
authors.initials: J
authors.lastname: Schäpe
authors.forename: Steffi
authors.initials: S
authors.lastname: Prausse
authors.forename: Manfred
authors.initials: M
authors.lastname: Radmacher
authors.forename: Reimer
authors.initials: R
authors.lastname: Stick
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D002467:Cell Nucleus / Q000378:metabolism*; D048430:Cell Shape; D004548:Elasticity; D005260:Female; D015870:Gene Expression; D034904:Lamin Type A / Q000378:metabolism*; D018625:Microscopy, Atomic Force; D009685:Nuclear Envelope / Q000378:metabolism; D009865:Oocytes / Q000166:cytology*; D014982:Xenopus laevis / Q000235:genetics
chemical_list: D034904:Lamin Type A