Deshpande A M, Newlon C S
Department of Microbiology and Molecular Genetics, University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark 07103-2174.
Mol Cell Biol. 1992 Oct;12(10):4305-13. doi: 10.1128/mcb.12.10.4305-4313.1992.
Replication origins have been mapped to positions that coincide, within experimental error (several hundred base pairs), with ARS elements. To determine whether the DNA sequences required for ARS function on plasmids are required for chromosomal origin function, the chromosomal copy of ARS306 was deleted and the chromosomal copy of ARS307 was replaced with mutant derivatives of ARS307 containing single point mutations in domain A within the ARS core consensus sequence. The chromosomal origin function of these derivatives was assayed by two-dimensional agarose gel electrophoresis. Deletion of ARS306 deleted the associated replication origin. The effects on chromosomal origin function of mutations in domain A paralleled their effects on ARS function, as measured by plasmid stability. These results demonstrate that chromosomal origin function is a property of the ARS element itself.
复制起点已被定位到在实验误差范围内（几百个碱基对）与自主复制序列（ARS）元件重合的位置。为了确定质粒上ARS功能所需的DNA序列对于染色体起点功能是否必要，删除了ARS306的染色体拷贝，并用含有ARS核心共有序列中A结构域单点突变的ARS307突变衍生物取代了ARS307的染色体拷贝。通过二维琼脂糖凝胶电泳分析这些衍生物的染色体起点功能。删除ARS306消除了相关的复制起点。如通过质粒稳定性所测定的，A结构域突变对染色体起点功能的影响与其对ARS功能的影响相似。这些结果表明染色体起点功能是ARS元件本身的一种特性。
