Recent studies confirm that stresses, including that due to gravity, tension, compression, pressure, and shear influence cell growth, differentiation, secretion, movement, signal transduction, and gene expression. Yet, little is known about how cells sense the mechanical stresses or deformations, and convert these mechanical signals into biological or biochemical responses. A possible mechno-chemical coupling mechanism involves protein conformational changes under mechanical forces. Our hypothesis is that mechanical forces can cause large changes of the conformation of proteins, which in turn can influence receptor-ligand binding. To test this hypothesis, molecular dynamics simulations and biochemical assays are performed.