Gagliardino J J, Krinks M H, Gagliardino E E
CENEXA-Centro de Endocrinología Experimental y Aplicada (UNLP-CONICET), Facultad de Ciencas Médicas, La Plata, Argentina.
Biochim Biophys Acta. 1991 Feb 19;1091(3):370-3. doi: 10.1016/0167-4889(91)90202-9.
The aim of this work was the identification of the calmodulin-stimulated protein phosphatase, calcineurin, in rat pancreatic islets. For this purpose, a high-affinity calcineurin antibody and the Western blotting technique were used to detect the presence of calcineurin in freshly collagenase-isolated islets. The calcineurin content detected by this method was about 0.30 ng islet (approx. 0.07% of the total islet protein). The subunit composition and Mr of islet calcineurin were similar to those of bovine brain calcineurin. Incubation of nitrocellulose membranes of the Western blotting, containing the islet protein fractions, with 125I-labeled calmodulin and 45Ca2+ demonstrated that the A subunit bound calmodulin, while the B subunit bound Ca2+. The presence of calcineurin in the islets of Langerhans would suggest its possible participation, as a counterpart of the kinases effect, in the regulatory mechanism of insulin secretion.
这项工作的目的是鉴定大鼠胰岛中的钙调蛋白刺激蛋白磷酸酶——钙调神经磷酸酶。为此，使用高亲和力的钙调神经磷酸酶抗体和蛋白质印迹技术来检测新鲜胶原酶分离的胰岛中钙调神经磷酸酶的存在。通过该方法检测到的钙调神经磷酸酶含量约为0.30 ng/胰岛（约占胰岛总蛋白的0.07%）。胰岛钙调神经磷酸酶的亚基组成和相对分子质量与牛脑钙调神经磷酸酶相似。用125I标记的钙调蛋白和45Ca2+孵育含有胰岛蛋白组分的蛋白质印迹硝酸纤维素膜，结果表明A亚基结合钙调蛋白，而B亚基结合Ca2+。朗格汉斯胰岛中存在钙调神经磷酸酶，这表明它可能作为激酶作用的对应物，参与胰岛素分泌的调节机制。
