c-myc基因中克隆的DNA复制起点能够以附加体状态在转基因小鼠中发挥功能并遗传下去。

Sudo K, Ogata M, Sato Y, Iguchi-Ariga S M, Ariga H

Institute of Medical Science, University of Tokyo, Japan.

Nucleic Acids Res. 1990 Sep 25;18(18):5425-32. doi: 10.1093/nar/18.18.5425.

The c-myc protein has recently been shown to interact with a region possessing putative origin of DNA replication and enhancer activities located 2 kb upstream of the c-myc gene itself. Transgenic mice were obtained by injecting constructs containing this region, termed pmyc(H-P), into fertilized mouse eggs. The transgenic elements were capable of efficient replication in all mouse tissues examined and were maintained in an episomal state even in highly differentiated cells. Moreover, pmyc(H-P) was transmittable to the progeny throughout several generations, which suggests that the fragment derived from the region upstream of the c-myc gene possesses sequences necessary for partition, stability and DNA replication of the plasmid in the cells. In addition, we have shown that the plasmid might be captured only by eggs, not by sperm.

最近研究表明，c-myc蛋白可与c-myc基因自身上游2 kb处一个具有假定DNA复制起始点和增强子活性的区域相互作用。通过将含有该区域（称为pmyc(H-P)）的构建体注射到受精小鼠卵中获得了转基因小鼠。转基因元件能够在所有检测的小鼠组织中高效复制，甚至在高度分化的细胞中也能以附加体状态维持。此外，pmyc(H-P)能够在几代中传递给后代，这表明源自c-myc基因上游区域的片段拥有质粒在细胞中进行分配、稳定和DNA复制所必需的序列。另外，我们已经证明该质粒可能仅被卵子捕获，而不被精子捕获。