title: Ferroelectric switching of elastin.
abstract: Ferroelectricity has long been speculated to have important biological functions, although its very existence in biology has never been firmly established. Here, we present compelling evidence that elastin, the key ECM protein found in connective tissues, is ferroelectric, and we elucidate the molecular mechanism of its switching. Nanoscale piezoresponse force microscopy and macroscopic pyroelectric measurements both show that elastin retains ferroelectricity at 473 K, with polarization on the order of 1 μC/cm(2), whereas coarse-grained molecular dynamics simulations predict similar polarization with a Curie temperature of 580 K, which is higher than most synthetic molecular ferroelectrics. The polarization of elastin is found to be intrinsic in tropoelastin at the monomer level, analogous to the unit cell level polarization in classical perovskite ferroelectrics, and it switches via thermally activated cooperative rotation of dipoles. Our study sheds light onto a long-standing question on ferroelectric switching in biology and establishes ferroelectricity as an important biophysical property of proteins. This is a critical first step toward resolving its physiological significance and pathological implications.
authors: Department of Mechanical Engineering, University of Washington, Seattle, WA 98195-2600;
authors: Yuanming
authors: Y
authors: Liu
authors: National Laboratory of Solid State Microstructures, Department of Physics, Nanjing University, Nanjing 210093, China;
authors: Hong-Ling
authors: HL
authors: Cai
authors: Departments of Mechanical Engineering andPhysics, University of Houston, TX 77204;
authors: Matthew
authors: M
authors: Zelisko
authors: Departments of Mechanical Engineering andBiomedical Engineering, Boston University, Boston, MA 02215;
authors: Yunjie
authors: Y
authors: Wang
authors: National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China; and.
authors: Jinglan
authors: J
authors: Sun
authors: Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China.
authors: Fei
authors: F
authors: Yan
authors: Department of Mechanical Engineering, University of Washington, Seattle, WA 98195-2600;
authors: Feiyue
authors: F
authors: Ma
authors: Department of Mechanical Engineering, University of Washington, Seattle, WA 98195-2600;
authors: Peiqi
authors: P
authors: Wang
authors: Department of Mechanical Engineering, University of Washington, Seattle, WA 98195-2600;
authors: Qian Nataly
authors: QN
authors: Chen
authors: Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China.
authors: Hairong
authors: H
authors: Zheng
authors: National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China; and.
authors: Xiangjian
authors: X
authors: Meng
authors: Departments of Mechanical Engineering andPhysics, University of Houston, TX 77204;
authors: Pradeep
authors: P
authors: Sharma
authors: Departments of Mechanical Engineering andBiomedical Engineering, Boston University, Boston, MA 02215;
authors: Yanhang
authors: Y
authors: Zhang
authors: Department of Mechanical Engineering, University of Washington, Seattle, WA 98195-2600; jjli@uw.edu.
authors: Jiangyu
authors: J
authors: Li
mesh_terms: D000818:Animals; D004549:Elastin / Q000737:chemistry* / Q000502:physiology; D004560:Electricity; D046529:Microscopy, Electron, Transmission; D056004:Molecular Dynamics Simulation; D013552:Swine; D013818:Thermogravimetry
chemical_list: D004549:Elastin