Nuclear mechanical resilience but not stiffness is modulated by αII-spectrin.
Spectrins are multi-domain, elastic proteins that provide elasticity to the plasma membrane of erythrocytes and select nucleated cells. Spectrins have also been found in the nucleus of non-erythrocytes, but their function remains to be uncovered. It has been hypothesized that a spring-like spectrin network exists within the lamina nucleoskeleton, however, experiments testing a spectrin network׳s mechanical impact on the nucleus are lacking. Here, we knock-down levels of nuclear αII-spectrin with the goal of disrupting this nucleoskeletal spectrin network. We mechanically test live cells with intranuclear particle tracking and compression assays to probe changes in nuclear mechanics with decreases in αII-spectrin. We show no changes in chromatin mechanics or in the stiffness of nuclei under compression. However, we do observe a reduction in the ability of nuclei with decreased αII-spectrin to recover after compression. These results establish spectrin as a nucleoskeletal component that specifically contributes to elastic recovery after compression.
Department of Chemical Engineering, Carnegie Mellon University, Pittsburgh, PA, USA.
Travis J
TJ
Armiger
Department of Chemical Engineering, Carnegie Mellon University, Pittsburgh, PA, USA.
Stephen T
ST
Spagnol
Department of Chemical Engineering, Carnegie Mellon University, Pittsburgh, PA, USA; Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, PA, USA. Electronic address: krisdahl@cmu.edu.
Kris Noel
KN
Dahl
D002467:Cell Nucleus / Q000502:physiology*; D006367:HeLa Cells; D006801:Humans; D013049:Spectrin / Q000502:physiology*; D013314:Stress, Mechanical
D013049:Spectrin
Lamina; Mechanobiology; Nucleoskeleton mechanics; Spectrins