Surprising Force-Dependent Unfolding of Titin Immunoglobulin Domain Revealed by Magnetic Tweezers

Titin is a giant muscle protein which helps to maintain the integrity of sarcomere. The folded or unfolded states of immunoglobulin domain in titin regulate the flexibility of muscle. How physiological force affects the unfolding rate is important to the function of titin. Using ultra-stable magnetic tweezers, we report systematic study of force-dependent unfolding dynamics of titin I27 immunoglobulin domain. Also the effect of low concentration of denaturant might be reported.