Interactions of calmodulin with coated vesicles from brain.
Interactions of calmodulin with coated vesicles from brain.
复制标题
钙调蛋白与大脑包被囊泡的相互作用。
DOI：
10.1073/pnas.78.1.308
复制
发表时间：
1981
影响因子：
11.1
通讯作者：
Roth,TF
中科院分区：
文献类型：
--
作者：
Linden,CD;Dedman,JR;Chafouleas,JG;Means,AR;Roth,TF
在钙存在下纯化的包被囊泡相对于在游离钙不存在下分离的标准制剂在钙调蛋白含量方面富集约7倍。放射性碘标记的钙调素在体外与包被囊泡特异性结合。结合是可饱和的（Kd，10 nM）和钙依赖性的。半最大结合发生在2.4 μ M游离Ca 2+，而高达1.2 mM Mg 2+对结合没有影响。肌钙蛋白C是一种与钙调蛋白同源的蛋白质，与125 I标记的钙调蛋白竞争结合，亲和力为天然钙调蛋白的1/30。在钙调素-琼脂糖柱上的2 M尿素溶解的包被囊泡的色谱法证明了包被囊泡蛋白和钙调素的Ca 2+依赖性相互作用。钙调素结合到包被囊泡的性质与其他系统中的钙调素活性的性质相当。
Coated vesicles purified in the presence of calcium are enriched approximately 7-fold in calmodulin content relative to standard preparations isolated in the absence of free calcium. Radioiodinated calmodulin binds specifically to coated vesicles in vitro. Binding is saturable (Kd, 10 nM) and calcium dependent. Half-maximal binding occurs at 2.4 microM free Ca2+ whereas up to 1.2 mM Mg2+ has no effect on binding. Troponin C, a protein homologous to calmodulin, competes with binding of 125I-labeled calmodulin with 1/30th the affinity of native calmodulin. Chromatography of 2 M urea-solubilized coated vesicles on a calmodulin-Sepharose column demonstrated a Ca2+-dependent interaction of coated vesicle proteins and calmodulin. The properties of calmodulin binding to coated vesicles are comparable to those of calmodulin activities in other systems.