盘基网柄菌(Dictyostelium discoideum)突变型细胞allC细胞周期异常的研究

细胞计数和细胞倍增时间计算的结果表明allC细胞的倍增时间为2.36h,仅为KAx-3细胞倍增时间的1/3。为了探究allC细胞倍增时间大幅度缩短、细胞周期异常的原因我们采用流式细胞术测定两种细胞的细胞周期,并结合实时荧光定量PCR技术测定cycB1和cdk1基因的相对表达量的比值。结果表明,16h突变型allC细胞处于G2期的数目(1.51%)显著少于KAx-3细胞(16.61%)。allC细胞和KAx-3细胞的细胞周期素B1(cyclinB1)cycB1基因相对表达量分别是2.5和0.25,两者相差10倍。这些数据表明,两种类型细胞中G2期的差异十分明显,cyclinB1的相对表达量也存在显著差异。提示cyclinB1的过表达可能在一定程度上影响allC细胞的细胞周期正常的调控机制,与突变细胞的G2期异常有一定关系。

The Study on Cell Cycle Abnormality in Dictyostelium discoideum allC Mutant Cell Line

The cell counting and cell doubling time calculation indicated that the allC muatant doubling time was 2.36h, it was only one third of KAx-3. To search for the reason of shortened the allC mutant doubling time, the function of cyclin B1, cell cycle of mutant cell and wild cell were studied by flow cytometry and real time-quantitative PCR. Cultured for 16 hours, the number of the mutant allC muatant (1.51%) in the G2 phase was significantly less than KAx-3 cells (16.61%). The relative expression level of cycB1 in allC mutant and KAx-3 were 2.5 and 0.24 respectively. It has demonstrated that the G2 phase of allC mutant was obviously shorter than KAx-3, as well as the relative expression level of cyclinB1 which was related closely to G2 phase regulation. Our results suggest that the overexpression of cyclinB1 in allC mutant might affect the normal cell cycle regulation to some extent, and it contributes to G2 phase abnormality.