http://physrev.physiology.org – Mechanotransduction, the conversion of a mechanical stimulus into a biological response, constitutes the basis for a plethora of fundamental biological processes such as the senses of touch, balance, and hearing and contributes critically to development and homeostasis in all organisms. Despite this profound importance in biology, we know remarkably little about how mechanical input forces delivered to a cell are interpreted to an extensive repertoire of output physiological responses. Read more »

http://www.jbc.org – Shear stress, the tangential component of hemodynamic forces, activates many signal transduction pathways in vascular endothelial cells. The conversion of mechanical stimulation into chemical signals is still unclear. We report here that shear stress (12 dynes/cm2) induced a rapid and transient tyrosine phosphorylation of Flk-1 and its concomitant association with the adaptor protein Shc; these are accompanied by a concurrent clustering of Flk-1, as demonstrated by confocal microscopy. Read more »

http://www.ejbjs.org – Fracture-healing is regulated in part by mechanical factors. Study of the processes by which the mechanical environment of a fracture modulates healing can yield new strategies for the treatment of bone injuries. This article focuses on several key unanswered questions in the study of mechanotransduction and fracture repair. Read more »

http://www.sciencedirect.com – Deletion or mutation of a variety of proteins localized at cell-matrix and cell-cell junctions, such as vinculin and its splice-variant metavinculin, can lead to dilated cardiomyopathy in mice and humans, leading some to hypothesize that these molecules are involved in mechanotransmission or mechanotransduction in the heart. To investigate cardiac mechanotransduction mechanisms in single cells, we have combined laser tweezers with a fluorescence resonance energy transfer (FRET) biosensor to apply localized forces and probe localized signaling events in isolated mouse ventricular myocytes. Read more »

http://www.jneurosci.org – Mechanosensory channels of sensory cells mediate the sensations of hearing, touch, and some forms of pain. The TRPA1 (a member of the TRP family of ion channel proteins) channel is activated by pain-producing chemicals, and its inhibition impairs hair cell mechanotransduction. As shown here and previously, TRPA1 is expressed by hair cells as well as by most nociceptors (small neurons of dorsal root, trigeminal, and nodose ganglia) and localizes to their sensory terminals (mechanosensory stereocilia and peripheral free nerves, respectively). Read more »

http://jp.physoc.org – In contrast to nearly all other sensory systems, the mechanically sensitive ion channel carrying the receptor current into hair cells of the inner ear has not been identified in molecular terms. A number of candidates from at least two different ion channel families have been considered: these include the epithelial sodium channel (ENaC) and acid-sensing ion channel (ASIC) members of the DEG/ENaC superfamily of amiloride-sensitive sodium channels, as well as the TRP channels TRPN1, TRPV4, TRPML3 and TRPA1. Read more »

http://hyper.ahajournals.org – High blood pressure induces a mechanical stress on vascular walls and evokes oxidative stress and vascular dysfunction. The aim of this study was to characterize the intracellular signaling causing vascular oxidative stress in response to pressure. In carotid arteries subjected to high pressure levels, we observed not only an impaired vasorelaxation, increased superoxide production, and NADPH oxidase activity, but also a concomitant activation of Rac-1, a small G protein. Read more »

http://jcb.rupress.org – An understanding of how the nuclear pore complex (NPC) mediates nucleocytoplasmic exchange requires a comprehensive inventory of the molecular components of the NPC and a knowledge of how each component contributes to the overall structure of this large molecular translocation machine. Therefore, we have taken a comprehensive approach to classify all components of the yeast NPC (nucleoporins). This involved identifying all the proteins present in a highly enriched NPC fraction, determining which of these proteins were nucleoporins, and localizing each nucleoporin within the NPC. Read more »

http://ajpcell.physiology.org – We constructed a model cytoskeleton to investigate the proposal that this interconnected filamentous structure can act as a mechano- and signal transducer. The model cytoskeleton is composed of rigid rods representing actin filaments, which are connected with springs representing cross-linker molecules. The entire mesh is placed in viscous cytoplasm. The Read more »

http://smartech.gatech.edu – Disease and degeneration of articular cartilage and fibrocartilage tissues severely compromise the quality of life for millions of people. Although current surgical repair techniques can address symptoms in the short term, they do not adequately treat degenerative joint diseases such as osteoarthritis. Thus, novel tissue engineering strategies may be necessary to combat disease progression and repair or replace damaged tissue. Read more »