title: Mechanical control of the sense of touch by β-spectrin.
abstract: The ability to sense and respond to mechanical stimuli emanates from sensory neurons and is shared by most, if not all, animals. Exactly how such neurons receive and distribute mechanical signals during touch sensation remains mysterious. Here, we show that sensation of mechanical forces depends on a continuous, pre-stressed spectrin cytoskeleton inside neurons. Mutations in the tetramerization domain of Caenorhabditis elegans β-spectrin (UNC-70), an actin-membrane crosslinker, cause defects in sensory neuron morphology under compressive stress in moving animals. Through atomic force spectroscopy experiments on isolated neurons, in vivo laser axotomy and fluorescence resonance energy transfer imaging to measure force across single cells and molecules, we show that spectrin is held under constitutive tension in living animals, which contributes to elevated pre-stress in touch receptor neurons. Genetic manipulations that decrease such spectrin-dependent tension also selectively impair touch sensation, suggesting that such pre-tension is essential for efficient responses to external mechanical stimuli.
authors.affiliation: 1] Department of Molecular and Cellular Physiology, Stanford University, Stanford, California 94305, USA [2] Department of Chemical Engineering, Stanford University, Stanford, California 94305, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Krieg
authors.affiliation: Department of Chemical Engineering, Stanford University, Stanford, California 94305, USA.
authors.forename: Alexander R
authors.initials: AR
authors.lastname: Dunn
authors.affiliation: Department of Molecular and Cellular Physiology, Stanford University, Stanford, California 94305, USA.
authors.forename: Miriam B
authors.initials: MB
authors.lastname: Goodman
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D017173:Caenorhabditis elegans; D029742:Caenorhabditis elegans Proteins / Q000502:physiology*; D048430:Cell Shape; D008465:Mechanoreceptors / Q000378:metabolism* / Q000502:physiology; D040542:Mechanotransduction, Cellular; D009068:Movement; D020125:Mutation, Missense; D054730:Protein Interaction Domains and Motifs / Q000235:genetics; D055503:Protein Multimerization; D013049:Spectrin / Q000502:physiology*; D014110:Touch; D014785:Vision, Ocular
chemical_list: D029742:Caenorhabditis elegans Proteins; C409166:unc-70 protein, C elegans; D013049:Spectrin