Wolowiec D, Ffrench M
Laboratoire de Cytologie Analytique et Cytogénétique Moléculaire, Université Claude Bernard, Lyon, France.
Pathol Biol (Paris). 1993 Jun;41(6):547-53.
Mitotic cyclins constitute a regulatory subunit of the histone H1 kinase complex. On the basis of primary structure differences, they are divided into two classes, A and B. Both classes are necessary for mitosis to occur. Cyclins A and B differ in the timing of their cellular expression and in their affinity with the various members of the cdk (cyclin-dependent kinases) family. They also have specific functions: cyclin A plays a role in DNA replication, whereas cyclin B are involved in the inhibition of the fusion of early endosomes and in the activation of cdc25 phosphatase. Cyclins A and B can contribute to the development of neoplastic disorders, either directly (inappropriate expression of the cyclin A gene caused by the hepatitis B virus in hepatocellular carcinoma, interactions between cyclin A and factors involved in the regulation of cell division), or indirectly by causing phosphorylation of oncogene products by a cdk.
有丝分裂周期蛋白构成组蛋白H1激酶复合物的调节亚基。根据一级结构差异，它们被分为A和B两类。这两类对于有丝分裂的发生都是必需的。周期蛋白A和B在细胞表达时间以及与细胞周期蛋白依赖性激酶（cdk）家族各成员的亲和力方面存在差异。它们也具有特定功能：周期蛋白A在DNA复制中起作用，而周期蛋白B参与抑制早期内体融合以及激活细胞分裂周期蛋白25（cdc25）磷酸酶。周期蛋白A和B可直接（如乙型肝炎病毒在肝细胞癌中导致周期蛋白A基因的不适当表达、周期蛋白A与参与细胞分裂调节的因子之间的相互作用）或间接通过导致cdk使癌基因产物磷酸化而促成肿瘤性疾病的发生。
