We study the role of integrins, dimeric receptors for extracellular matrix, in cardiac myocytes. Integrins are interposed between the contractile machinery of the cardiac muscle and the extracellular matrix skeleton of the heart. The integrin receptors serve as mechanosensors, translating mechanical stress into chemical signals. We study this process using a novel transgenic mouse system, in which integrin expression by cardiac myocytes is turned on and off using a chemical switch (Transgenic Research 10: 269-75). Using a similar approach, we are studying the role of the natriuretic peptide system in mediating diastolic left ventricular function. These projects are ideal for students wishing to learn more about the basic pathobiology of the heart using molecular, cell, transgenic and physiological approaches.