Abstract: A distinction method is provided to distinguish catch capacity where myosin, a protein that constitutes muscles, or filaments containing myosin bind to actin due to the contribution of twitchin that constitutes thick filaments along with myosin, while certain tension is sustained. The catch capacity is distinguished by using synthetic thick filaments containing myosin and twitchin, which are obtained from an extract of the muscles with a predetermined high salt buffer solution, and a soluble protein fraction obtained from the suspension of the above-mentioned muscles.

Abstract: Since the mechanism of conversion of the state of actin and myosin or the filaments containing myosin from the relaxed to the catch had not been totally clear and its reconstitution was not easily carried out, a method of converting the state of the muscle proteins from the relaxed state, where said actin does not bind to myosin or filaments containing myosin, to the catch state, where actin binds to myosin or the filaments containing myosin and the binding can sustain a certain tension with low energy expenditure, is accomplished by using a phosphatase called serine/threonine protein phosphatase 2B dephosphorylating twitchin. The phosphatase forms thick filaments along with myosin, and at the same time, the state is converted from the catch state to the relaxed state by using a protein kinase A phosphorylating twitchin, and thus the state can be reversibly converted between the catch and the relaxed states.

Abstract: A distinction method is provided to distinguish catch capacity where myosin, a protein that constitutes muscles, or filaments containing myosin bind to actin due to the contribution of twitchin that constitutes thick filaments along with myosin, while certain tension is sustained. The catch capacity is distinguished by using synthetic thick filaments containing myosin and twitchin, which are obtained from an extract of the muscles with a predetermined high salt buffer solution, and a soluble protein fraction obtained from the suspension of the above-mentioned muscles.

Abstract: A method and an apparatus for measuring the microforce acting between a micro particle fixed on the probe and the observation plane are described. The probe is feedback-controlled to be held motionless by canceling probe displacements caused by movements of the micro particle fixed on the probe, using irradiation pressure provided by a laser that applies photon pressure. The microforce acting between the micro particle fixed on the probe and the observation plane is measured by recording the time-varying laser output power. This allows probe fluctuations to be reduced to a few angstroms, and permits control of the distance to the target object to within a few nm, enabling measurement of microforces on the order of 0.1 pN.

Abstract: A method and an apparatus for measuring the microforce acting between a micro particle fixed on the probe and the observation plane are described. The probe is feedback-controlled to be held motionless by canceling probe displacements caused by movements of the micro particle fixed on the probe, using irradiation pressure provided by a laser that applies photon pressure. The microforce acting between the micro particle fixed on the probe and the observation plane is measured by recording the time-varying laser output power. This allows probe fluctuations to be reduced to a few angstroms, and permits control of the distance to the target object to within a few nm, enabling measurement of microforces on the order of 0.1 pN.