Expression And Regulation Of Cyclin G1 In Mouse Granulosa Cells

Cell cycle which associated with many diseases in human being espcially the tumor, can be regulated by the interaction of nagtive growth factors and the positive factors.The factors include cdc gene, cyclin dependent kinase(CDK) and cyclins. As a special kind of protein, cyclins play the important role in regulating cell cycle. Up to now, at least 16 cyclins have been identified in mammalian cells.They act in specific stage of cell cycle.and regulate the cell proliferation and differentiation.Cyclin G1 which was first identified serendipitously in screening for src family kinases in rat fibroblasts is expressed at high levels in skeletal muscle, ovary and kidney, but the function of cyclin G1 has not been determined. As transcriptional targets of p53, cyclin G1 can be transactivated by wild-type p53, which implicate cyclin G1 play a negative role in cell cycle arrest after DNA damage, DNA repair and cell apoptosis. On the other hand, cyclin G1 may act as a positive factor in cell growth and proliferation. It has different roles in different tissue that may be related to the expression level of cyclin G1. In 1996, Mary C. Horne pointed that cyclin G1 was expressed at high levels in...