The construction of multi-chromatin inducible human artificial chromosome (HAC)

在人类着丝粒上，各种染色质(如着丝粒染色质、异染色质)聚集在高度重复的DNA(阿尔菲DNA)上。有人认为，每个染色质对着丝粒功能都是重要的，然而，不同的染色质在同一DNA上的积累机制以及着丝粒活性的维持和调节机制仍不清楚。对含有四环素操纵子(Teto)的人人工染色体(HAC)的分析表明，着丝粒上各种染色质之间的平衡直接影响着丝粒的活性。为了详细分析染色质的作用，我们构建了另一个含有乳糖操纵子的人工合成α-DNA(LACO)。在TeTO/LACO着丝粒DNA串联阵列上，TetR或LacI融合蛋白可以单独诱导不同的染色质修饰。

At the human centromere, various chromatins (e.g. centromere chromatin, heterochromatin) assemble on the highly repetitive DNA (alphoid DNA). Is has been suggested that each chromatin is important for centromere functions, however, the accumulation mechanism of different chromatins on the same DNA and the mechanism of maintenance and regulation of centromere activity are still unknown. From the analyses of a human artificial chromosome (HAC) containing tetracycline operator (tetO), it has been suggested that the balance between various chromatins on centromere directly affected the centromere activity. To analyze the roles of chromatins in detail, we constructed another synthetic alphoid DNA containing lactose operator (lacO). On the tandem array of tetO / lacO centromere DNA, various chromatin modifications could be induced individually by the tethering of tetR- or lacI- fusion proteins.