Hela Chromatin Structure Change Dynamically In Interphase Cells

The carrier of eukaryotic DNA genome is chromatin, which is made of a small amount of RNA, DNA, histones and non-histones, a highly-changed complex in the process of cell cycle. The highly helical chromosomes in the splitting period are formed by interphase chromatin folding together continuously. Chromatin and chromosomes are performance status of the same substance in different periods. Gene replication and transcription occurs on the looser of chromatin. Chromatin conformation plays an important role in the regulation of eukaryotic gene expression. Studies on change of chromosome in a divided period are already very thoroughly. However, The research subjects of study on how chromosomes set shrinks into a loose chromatin in the specific cell division period at the end from the beginning, and how chromatin condense into a chromosome during the cell interphase G1, S, G2are mostly about higher plants, and people know little about mammalian cell chromatin cycle changes. Based on HeLa cell as the research object, this thesis takes the method to collect sampling according to the process of cell cycle synchronization, Using conventional electron microscopy and specific DNA staining analysis respectively, comparing the chromatin structure behavior in interphase cells. The results for the interphase chromatin structure and function to provide relevant basis.The results are as follows:1> Conventional and stereo electrons microscopy, and a specific DNA staining both showed that chromatin structure of HeLa dynamically changed in interphase, making condensation and decondensation. With other biological material consistent with the results of electron microscope, it’s some support for chromatin structure change dynamically in interphase cells.2> We observed that chromatin structure condensation behavior happened twice Heterochromatin set condensation in early S period,it’s about the size of0.33μm; euchromatin set condensation in the end of S period, its size is approximately0.19-0.32μm; and all chromatin set decondensation during the middle of S period, they are about the size of0.07μm. To further study the euchromatin and heterochromatin structure and function relationships provide relevant basis.