title: Neurofilaments Function as Shock Absorbers: Compression Response Arising from Disordered Proteins.
abstract: What can cells gain by using disordered, rather than folded, proteins in the architecture of their skeleton? Disordered proteins take multiple coexisting conformations, and often contain segments which act as random-walk-shaped polymers. Using x-ray scattering we measure the compression response of disordered protein hydrogels, which are the main stress-responsive component of neuron cells. We find that at high compression their mechanics are dominated by gaslike steric and ionic repulsions. At low compression, specific attractive interactions dominate. This is demonstrated by the considerable hydrogel expansion induced by the truncation of critical short protein segments. Accordingly, the floppy disordered proteins form a weakly cross-bridged hydrogel, and act as shock absorbers that sustain large deformations without failure.
authors.affiliation: Raymond and Beverly Sackler School of Physics and Astronomy, Tel Aviv University, Ramat Aviv, Tel Aviv 69978, Israel.
authors.forename: Micha
authors.initials: M
authors.lastname: Kornreich
authors.affiliation: Raymond and Beverly Sackler School of Physics and Astronomy, Tel Aviv University, Ramat Aviv, Tel Aviv 69978, Israel.
authors.forename: Eti
authors.initials: E
authors.lastname: Malka-Gibor
authors.affiliation: Raymond and Beverly Sackler School of Physics and Astronomy, Tel Aviv University, Ramat Aviv, Tel Aviv 69978, Israel.
authors.forename: Ben
authors.initials: B
authors.lastname: Zuker
authors.affiliation: Raymond and Beverly Sackler School of Physics and Astronomy, Tel Aviv University, Ramat Aviv, Tel Aviv 69978, Israel.
authors.forename: Adi
authors.initials: A
authors.lastname: Laser-Azogui
authors.affiliation: Raymond and Beverly Sackler School of Physics and Astronomy, Tel Aviv University, Ramat Aviv, Tel Aviv 69978, Israel.
authors.forename: Roy
authors.initials: R
authors.lastname: Beck
mesh_terms: D020100:Hydrogels; D007382:Intermediate Filaments / Q000737:chemistry*; D011108:Polymers; D011487:Protein Conformation; D017510:Protein Folding; D011506:Proteins / Q000378:metabolism
chemical_list: D020100:Hydrogels; D011108:Polymers; D011506:Proteins