着丝粒蛋白B在基因组未复制的有丝分裂期细胞中的表达

着丝粒蛋白Ｂ（ＣＥＮＰ－Ｂ）主要位于染色体着丝粒区域的中心域，是一种ＤＮＡ结合蛋白，与染色体着丝粒、动粒的结构形成与功能实施有关。本研究结果显示咖啡因可以诱导ＣＨＬ细胞发生ＭＵＧ细胞。利用核酸杂交技术证明了在ＣＨＬ细胞中存在ＣＥＮＰ－Ｂ基因，并研究了咖啡因诱导ＭＵＧ细胞形成过程中ＣＥＮＰ－Ｂ的基因表达。发现ＣＥＮＰ－Ｂ在ＭＵＧ细胞整个过程中均有表达，表现出表达持续性。这与我们在Ｈｅｌａ细胞中发现的

CENTROMERE PROTEIN B GENE EXPRESSION IN MUG CELLS

When CHL cells were arrested at the G1/S boundary of the cell cycle by treatment with 2. 4mmol/L hydroxyurea for 20h and subsequently treated with caffeine(5mmol/L),MUG cells(mitotic cells with unreplicated genome) were observed. ACA immunostaining showed that the kinetochores were arranged in the center of the MUG cells,while the fragmented chromosomes were distributed throughout the whole cytoplasm. The combined treatment of caffeine and colcemid resulted in the dispersed kinetochore staining .We demonstrated for the first time the existence of CENP-B gene in CHL cells by Southern blot and examined the CENP-B gene expression during the process of MUG cell induction by caffeine.CENP-B gene was expressed in the MUG cells treated with caffeine for 4 and sh ,but lower than in cells at G1/S boundary.The fact that CENP-B gene was always in a state of expression in hydroxyurea treated cells which were at the G1/S boundary and in MUG cells suggested that the continous expression of CENP-B may play an important role in the implement of the kinetochore function.