Kato A, Ota S, Bamba H, Wong R M, Ohmura E, Imai Y, Matsuzaki F
1st Department of Internal Medicine, Saitama Medical Center, Saitama Medical School, 1981 Tsujido, Kamoda, Saitama, Kawagoe, 350-8550, Japan.
Biochem Biophys Res Commun. 1998 Apr 7;245(1):70-4. doi: 10.1006/bbrc.1998.8377.
The regulation of cyclin D-dependent kinase activity in tissue regeneration in vivo has not been fully described. In young adult rat liver after 70% partial hepatectomy, the association of cyclin D1 with cdk4 was significantly promoted during G1 phase and was maximal at 18 hr, corresponding mainly to late G1. Cyclin D1-dependent kinase activity also strongly increased during G1 phase. The timing of the induction of cyclin D1 / cdk4 complex assembly correlated well with that of cyclin D1-dependent kinase activity. At 18 hr after partial hepatectomy, the amounts of CDK inhibitors p21(CIP1) and p27(KIP1) were also maximal, while only one-tenth of p21(CIP1) and of p27(KIP1) was associated with cyclin D1. These findings suggest that cyclin D1, cdk4 and their association act as promoting factors, and that both p21(CIP1) and p27(KIP1) may have physiological functions as adaptor proteins in additions to their roles as CDK inhibitors in rat liver regeneration.
细胞周期蛋白D依赖性激酶活性在体内组织再生中的调控尚未得到充分描述。在70%部分肝切除术后的成年大鼠肝脏中，细胞周期蛋白D1与细胞周期蛋白依赖性激酶4（cdk4）的结合在G1期显著增强，并在18小时时达到最大值，主要对应于G1晚期。细胞周期蛋白D1依赖性激酶活性在G1期也强烈增加。细胞周期蛋白D1/cdk4复合物组装诱导的时间与细胞周期蛋白D1依赖性激酶活性的时间密切相关。部分肝切除术后18小时，细胞周期蛋白依赖性激酶抑制剂p21（CIP1）和p27（KIP1）的量也达到最大值，而只有十分之一的p21（CIP1）和p27（KIP1）与细胞周期蛋白D1相关联。这些发现表明，细胞周期蛋白D1、cdk4及其结合起促进因子的作用，并且p21（CIP1）和p27（KIP1）除了作为细胞周期蛋白依赖性激酶抑制剂在大鼠肝脏再生中发挥作用外，还可能作为衔接蛋白具有生理功能。
