哺乳類細胞のゲノム構造に関する新奇仮説Ⅱ

-多倍体細胞への展開-

抄録

A new model for the genome structure of mammalian polyploid cells is introduced. It was constructed using the fractal structure model that was described in the preceding review. When cell division is inhibited and DNA syn thesis progresses, replicated DNA will be stacked keeping the initial structure of opposite-handed twin-circles. When inhibitors are removed, the polyploidized cells may return to the initial ploidy, because the stacked DNA loops have not been linked. When the stacked DNA twin-loops are linked with a proper configuration, the cells may become polyploid cells that can proliferate. There is a distinct difference in the genome structure between polyploidized and polyploid cells. The ploidy of polyploid cells is not stable, because the homologous chromo somes are arrayed mirror-symmetrically. The polyploid cells can return abruptly to a diploid state and repossess the point symmetry, or they gradually decrease the DNA level and become stable hypoploid cells whose DNA structure deviates from mirror symmetry. Experimental results will be introduced to verify the prediction.