Watterson D M, Mendel P A, Vanaman T C
Biochemistry. 1980 Jun 10;19(12):2672-6. doi: 10.1021/bi00553a020.
Calmodulins have been purified from porcine, rabbit, rat, and chicken brains and their structural and functional properties compared to those of the bovine brain protein whose complete amino acid sequence has been elucidated. No major differences were detected in the amino acid compositions and tryptic peptide maps of these five proteins. All calmodulins lacked tryptophan and cysteine and contained 1 mol of N epsilon-trimethyllysine and histidine per mol of protein. Bovine, porcine, rabbit, rat, and chicken brain calmodulins comigrated on polyacrylamide gels run under a variety of conditions in the presence and absence of denaturants. All brain calmodulins gave identical profiles for the calcium-dependent activation of "activatable" bovine brain 3',5'-cyclic nucleotide phosphodiesterase. In addition, they formed calcium-dependent complexes with rabbit skeletal muscle troponin I and the electrophoretic mobilities of the complexes were identical with one another and similar to the corresponding complex between troponin I and troponin C. These studies more fully define what is a calmodulin, demonstrate that calmodulin is a relatively invariant constituent of vertebrate brain, and indicate that calmodulin structure and function have been highly conserved throughout vertebrate evolution.
已从猪脑、兔脑、大鼠脑和鸡脑中纯化出钙调蛋白，并将它们的结构和功能特性与已阐明完整氨基酸序列的牛脑蛋白的结构和功能特性进行了比较。在这五种蛋白质的氨基酸组成和胰蛋白酶肽图中未检测到重大差异。所有钙调蛋白都不含色氨酸和半胱氨酸，每摩尔蛋白质含有1摩尔的N-ε-三甲基赖氨酸和组氨酸。在有变性剂和无变性剂的各种条件下进行聚丙烯酰胺凝胶电泳时，牛脑、猪脑、兔脑、大鼠脑和鸡脑的钙调蛋白会一起迁移。所有脑钙调蛋白对“可激活的”牛脑3',5'-环核苷酸磷酸二酯酶的钙依赖性激活都给出相同的图谱。此外，它们与兔骨骼肌肌钙蛋白I形成钙依赖性复合物，并且这些复合物的电泳迁移率彼此相同，并且类似于肌钙蛋白I和肌钙蛋白C之间的相应复合物。这些研究更全面地定义了什么是钙调蛋白，证明钙调蛋白是脊椎动物脑相对不变的组成部分，并表明钙调蛋白的结构和功能在整个脊椎动物进化过程中得到了高度保守。
