人工染色体技術とゲノム編集技術を用いた創薬研究への応用

抄録

The vectors for expressing genes in mammalian cells and animals has not only been a tool for analyzing gene functions, but also has played an important role in industrial and medical applications. In the conventional transgenic technology, the size of DNA that can be introduced into mammalian cells and animals is usually limited to several hundred kb, and to introduce genes or gene clusters having a size exceeding 1 Mb has been impossible. To solve these problems, we used chromosome engineering technology to develop human artificial chromosomes (HAC) and mouse artificial chromosomes (MAC) that can carry large human genes, multiple human genes in a stable manner. On the other hand, the endogenous gene or gene cluster that corresponds to the human GOI(s) being transferred needs to be disrupted to generate a fully humanized animal model. Cre/loxP-mediated deletion of large genomic regions in mouse ESCs has been used to generate gene cluster KO mice. However, this is labor intensive and time consuming because the targeting of two loxP sites and Cre/loxP-mediated chromosomal deletion via Cre expression must be performed in mouse ESCs. To overcome this limitation, genome editing technologies such as ZFN, TALEN, and CRISPR/Cas9 have been utilized to induce large genomic deletions and generate orthologous gene cluster KO animals. These technologies can also be used to further modify previously constructed HACs/MACs carrying human genomic regions. Therefore, the combination of chromosome transfer and genome editing technology is requisite for the efficient production of fully humanized animals. In this symposium, I will introduce new drug discovery tools developed by HAC/MAC and genome editing technology, and further introduce new combined technologies of DNA synthesis and HAC/MAC.