Calcium ion-dependent regulation of uterine smooth muscle thin filaments by caldesmon
S Marston - American journal of obstetrics and gynecology, 1989 - Elsevier
Native thin filaments were extracted from rabbit uterus by the procedure of Marston and
Smith. The protein content was actin, tropomyosin, and caldesmon in molar ratios of 1: 0.2:
0.03. Some filamin, myosin, and calcium-binding protein were also present. The thin
filaments activated skeletal or smooth muscle myosin magnesium adenosine triphosphatase
at least 30-fold. Activation was regulated by Ca 2+; maximum observed Ca 2+ sensitivity
was> 10 times. The thin filaments were dismantled into component proteins by the method of …
Smith. The protein content was actin, tropomyosin, and caldesmon in molar ratios of 1: 0.2:
0.03. Some filamin, myosin, and calcium-binding protein were also present. The thin
filaments activated skeletal or smooth muscle myosin magnesium adenosine triphosphatase
at least 30-fold. Activation was regulated by Ca 2+; maximum observed Ca 2+ sensitivity
was> 10 times. The thin filaments were dismantled into component proteins by the method of …
