α-Actinin, a New Structural Protein from Striated Muscle
I. Preparation and Action on Actomyosin-ATP Interaction
1965 年 58 巻 1 号 p. 7-12
詳細
1965 年 58 巻 1 号 p. 7-12
1. A new protein, named α-actinin, was extracted from rabbit skeletal muscle and its effect on the shrinking process of actomyosin was studied by turbidometric method.
2. α-Actinin has a remarkable accelera-ting effect on the superprecipitation process of actomyosin. The presence of α-actinin allowed superprecipitation to take place at higher ionic strength and increased the degree of shrinking of actomyosin.
3. Usual actin preparation was shown to contain more or less α-actinin. Interaction between myosin and α-actinin-free actin was very weak under the usual conceneration of ATP, i.e., superprecipitation was hardly obser-vable under this condition. Addition of α-actinin greatly strengthened the interaction between actin and myosin and gave rise to a remarkable superprecipitation.
4. The amino acid composition of α-actinin resembles that of actin. Some other properties of α-actinin are also somewhat similar to those of denatured actin. However, the denatured actin did not show any promo-ting effect on superprecipition.
5. The role of α-actinin in the mechanism of muscular contraction is discussed.
We would like to express our sincere thanks to Dr. K. Maruyama for his advice and discussions. Our thanks are also due to Miss A. Kodama for her technical assistance.
