CHARACTERIZATION OF HUMAN ORIGIN RECOGNITION COMPLEX

DNA复制是细胞分裂和 扩散。细胞周期调控过程是细胞周期调控的重要目标 因为DNA的准确复制对生存能力至关重要 恰好在正确的时间。此过程中的失败通常会导致 基因组中的突变。此外，基因组的稳定性可能会受到损害。 如果DNA复制完成，或者是否存在局部重新启动 复制，因为在复制过程中会发生DNA的异常分割 有丝分裂。这类违规行为已被发现与 患有不同类型的癌症。这类违规行为一直是 被发现与不同类型的癌症有关。因此，澄清 DNA复制的调节和机制将有助于 设计更新的药物来对抗这些疾病。目前，它的起源 DNA复制或识别它们的蛋白质尚未确定 并在人类和其他哺乳动物身上表现出非常详细的特征。要开始 为了区分这些来源，我们首先提出从人类细胞中提纯 从人类细胞中纯化一组蛋白质，即起源识别复合体 (ORC)，它被推定为与原产地绑定。然后，我们打算确定 人ORC的靶向结合位点并鉴定其特异性 蛋白质-DNA相互作用，最后，我们希望克隆剩余的亚基 人类的兽人。这些研究是迈向 人类复制起源的详细特征。更多 值得注意的是，该提案是开发 人类无细胞系统，能够启动DNA合成 特定的人类起源，这将是旨在 阐明DNA复制启动的确切机制。

DNA replication is an essential prelude to cell division and proliferation. The process is an important target of cell cycle control because it is critical for viability that the DNA is copied accurately and precisely at the correct time. Failure in this process generally leads to mutations within the genome. Moreover, genome stability may be compromised if DNA is replicated completely or if there is local re-initiation of replication because abnormal partitioning of the DNA would occur during mitosis. These kinds of irregularities have been found to be associated with different types of cancer. These kinds of irregularities have been found to be associated with different types of cancer. Thus, elucidating the regulation and mechanism of DNA replication would be useful for designing newer drugs to combat these diseases. At present, the origins of DNA replication or proteins that recognize them have not been identified and characterized in great detail in humans and other mammalians. To begin to distinguish these origins, we first propose to purify from human cells purify from human cells a set of proteins, the origin recognition complex (ORC), that is presumed to bind to origins. We then intend to identify the target binding sites of human ORC and characterize the specificity of the protein-DNA interactions, Lastly, we wish to clone the remaining subunits of human ORC. These studies are an important first step towards the detailed characterization of human origins of replication. More significantly, this proposal is essential groundwork for developing a human cell-free system that is capable of initiating DNA synthesis from a specific human origin, which will be crucial for experiments designed to elucidate the precise mechanism of initiation of DNA replication.