Larson R E, Pitta D E, Ferro J A
Departamento de Bioquímica, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Brasil.
Braz J Med Biol Res. 1988;21(2):213-7.
We present evidence for a novel calmodulin-binding protein associated with Ca2+-sensitive, non-muscle actomyosin from rabbit brain. Gel filtration chromatography of brain actomyosin and SDS-PAGE analysis of resulting fractions revealed the presence of a stable complex of a 190 kDa polypeptide and calmodulin. Furthermore, brain actomyosin was retained on a column of conjugated calmodulin-Sepharose 4B and eluted by 6 M urea in the presence of Ca2+. Further elution with 6M urea plus EGTA released the 190 kDa polypeptide from the column. These results show that the 190 kDa polypeptide forms a tight complex with calmodulin and that this complex associates with brain actomyosin in a Ca2+-independent manner.
我们提供了一种与兔脑Ca2+敏感的非肌肉肌动球蛋白相关的新型钙调蛋白结合蛋白的证据。对脑肌动球蛋白进行凝胶过滤色谱分析，并对所得馏分进行SDS-PAGE分析，结果显示存在一种由190 kDa多肽和钙调蛋白组成的稳定复合物。此外，脑肌动球蛋白保留在偶联钙调蛋白-琼脂糖4B柱上，并在Ca2+存在的情况下用6 M尿素洗脱。用6 M尿素加EGTA进一步洗脱可使190 kDa多肽从柱上释放。这些结果表明，190 kDa多肽与钙调蛋白形成紧密复合物，且该复合物以不依赖Ca2+的方式与脑肌动球蛋白结合。
