Weiss U, Wilson J H
Verna and Marrs McLean Department of Biochemistry, Baylor College of Medicine, Houston, TX 77030.
Nucleic Acids Res. 1988 Mar 25;16(5):2313-22. doi: 10.1093/nar/16.5.2313.
We have shown previously that heteroduplexes containing single-stranded loops are repaired efficiently in monkey cells, but not always correctly: 2% of the repair products acquired mutations within a 350 base-pair target (Weiss, U. and Wilson, J.H., Proc. Natl. Acad. Sci. USA 87:1123-1126, 1987). The structures of the mutant genomes, which are described here, are consistent with an error-prone repair system. The spectrum of mutations includes about 25% point mutations and 75% rearrangements, which consist of deletions, duplications, and substitutions. The mutations are clustered in the vicinity of single-stranded loops in the original heteroduplex. The high frequency of mutation, their clustering, and the positions of rearrangement endpoints suggest that the mutations were generated during repair of the heteroduplexes.
我们之前已经表明，含有单链环的异源双链体在猴细胞中能被高效修复，但并不总是正确修复：2%的修复产物在一个350个碱基对的靶标内发生了突变（魏斯，U.和威尔逊，J.H.，《美国国家科学院院刊》87:1123 - 1126，1987）。这里描述的突变基因组结构与一个易错修复系统一致。突变谱包括约25%的点突变和75%的重排，重排由缺失、重复和替换组成。这些突变聚集在原始异源双链体中单链环的附近。突变的高频率、它们的聚集以及重排端点的位置表明这些突变是在异源双链体修复过程中产生的。
