Mason P A, Nelson D L
Department of Biochemistry, College of Agricultural and Life Sciences, University of Wisconsin-Madison 53706.
Biochim Biophys Acta. 1989 Jan 17;1010(1):108-15. doi: 10.1016/0167-4889(89)90190-0.
The cAMP-dependent protein kinases of the cilia of the protozoan Paramecium tetraurelia were resolved and characterized. Two cAMP-dependent activities were present in cilia; the two ciliary kinases resemble types I and II from vertebrate tissues. Part of the ciliary kinase activity (primarily type II) was released by freeze-thawing, but a significant amount remained particulate. Both kinases were found as aggregates of about 220 kDa and of about 70 kDa. A portion of the cAMP-binding activity in ciliary extracts separated from kinase activity, and eluted at 36 kDa during gel filtration. Photoaffinity labeling with 8-azido-cAMP identified cAMP-binding proteins of 45-52 kDa in type II kinase from cilia, and of 43-46 kDa in type I kinase. The type II kinase was apparently autophosphorylated, causing a decrease in mobility during sodium dodecyl sulfate-polyacrylamide gel electrophoresis.
对原生动物四膜虫纤毛中的环磷酸腺苷（cAMP）依赖性蛋白激酶进行了分离和表征。纤毛中存在两种cAMP依赖性活性；这两种纤毛激酶类似于脊椎动物组织中的I型和II型。部分纤毛激酶活性（主要是II型）通过冻融释放，但仍有大量保持颗粒状。两种激酶均以约220 kDa和约70 kDa的聚集体形式存在。纤毛提取物中的一部分cAMP结合活性与激酶活性分离，并在凝胶过滤过程中于36 kDa处洗脱。用8-叠氮基-cAMP进行光亲和标记，在纤毛II型激酶中鉴定出45-52 kDa的cAMP结合蛋白，在I型激酶中鉴定出43-46 kDa的cAMP结合蛋白。II型激酶显然发生了自身磷酸化，导致在十二烷基硫酸钠-聚丙烯酰胺凝胶电泳过程中迁移率降低。
