Chaperone activity of α-crystallin in relation to the sarcoplasmic reticulum Ca2+ pump of skeletal muscles in stress and adaptation

α-Crystallin, an endogenous low-molecular-weight protein with chaperone activity, exerted protective effects on membrane systems of Ca2+ transport into the sarcoplasmic reticulum of skeletal muscles. Protective action of α-crystallin depended on the body state. This effect was not observed in the control and after adaptation to stress, while after stress, especially against the background of adaptation, α-crystallin increased the rate of Ca2+ transport into the sarcoplasmic reticulum and thermal resistance of Ca2+ pump. The mechanisms of α-crystallin activation during stress are discussed.