Showing papers on "Mechanotransduction published in 1991"

Function follows form : generation of intracellular signals by cell deformation

Abstract: Cells are exposed during their lifetimes to an array of physical forces ranging from those generated by association with other cells and extracellular matrices to the constant forces placed on cells by gravity. Alterations in these forces, either with differentiation and development or changes in activity or behavior, result in modifications in the biochemistry and adaptation in structure and function of cells. Also, a variety of differentiated cells have unique shapes that relate to extremely specialized functions, with structure and function emerging concurrently. These observations lead to the concept that the forces perceived by cells may dictate their shape, and the combined effects of external physical stimuli and internal forces responsible for maintaining cell shape may stimulate alterations in cellular biochemistry. This review examines the state of our knowledge concerning the mechanisms through which physical forces are converted to biochemical signals (mechanotransduction), and speculates on the molecular structures that may be involved in mechanotransduction.

Actin binding proteins--lipid interactions.

Abstract: Publisher Summary The actin-binding proteins–lipid interactions at the plasma membrane interface are considered via two aspects: first, generation of intracellular signals or second messengers—besides the classical receptor pathway—may involve mechanical stimuli that are produced by applying physical forces to the cell surface. This process of mechanotransduction allows function to follow a given form and represents a new concept. Second, it was proposed that the topogenesis of a membrane skeleton is determined by assembly limiting reaction steps. Hence, actin-binding protein–lipid interactions play a central role not only in mediating the anchorage of the cytoskeleton in the lipid layer, but also in defining a specific membrane topology. Moreover, the release of actin-binding proteins or certain lipids from their complex upon stimulation via receptors may represent a more direct way for a cell to trigger intracellular events through a transmembrane signaling mechanism.

Morphological correlates of mechanotransduction in acousticolateral hair cells.

Abstract: The development of ideas on mechanotransduction in acousticolateral hair cells is described, leading to the current idea that transduction depends on deflection of the bundle of stereocilia by a force parallel to the plane of the sensory epithelium. Electrophysiological experiments are summarised, suggesting that transduction depends on a shear between the different rows of stereocilia, and that the transducer channels are situated towards the tips of the stereocilia. Analysis of the ways that shear between the rows of stereocilia could be detected suggests that tip links are the structures which are most likely to transmit the stimulus-induced forces to the transducer channels on the membrane. The directional selectivity of mechanotransduction is associated with the position of the kinocilium and gradation in heights of the stereocilia; evidence is presented suggesting that in the lateral line these are partly determined by the mitosis giving rise to the hair cell. Tip links differentiate out of links which initially join the stereocilia in all directions, with their final spatial organisation, which sets the directional selectivity of mechanotransduction, probably being determined by the gradient in growth of the stereocilia.