METHYL-DIRECTED REPAIR OF FRAMESHIFT MUTATIONS IN HETERODUPLEX DNA
METHYL-DIRECTED REPAIR OF FRAMESHIFT MUTATIONS IN HETERODUPLEX DNA
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DOI：
10.1073/pnas.83.10.3395
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发表时间：
1986-05-01
影响因子：
11.1
通讯作者：
RADMAN, M
中科院分区：
文献类型：
--
作者：
DOHET, C;WAGNER, R;RADMAN, M
通过退火分离的噬菌体链制备具有四种不同类型的单个未配对碱基的DNA异源双链体。DNA并用于检测大肠杆菌。从转染的细菌获得的子代细胞的遗传分析表明，E。大肠杆菌错配修复系统可以识别和修复具有单个未配对碱基的异源双链体-即，移码/野生型异源双链体。异源双链体的特定链的修复被该链的GATC序列中的腺嘌呤的完全甲基化抑制。因此，E.大肠杆菌错配修复系统可以作用于新合成的DNA链，以消除涉及单个碱基插入或缺失的复制错误。
DNA heteroduplexes with single unpaired bases of the four different kinds were prepared by annealing separated strands of bacteriophage .lambda. DNA and used to transfect Escherichia coli. Genetic analysis of the progeny phages obtained from transfected bacteria indicates that the E. coli mismatch repair system can recognize and repair heteroduplexes with single unpaired bases-i.e., frameshift/wild-type heteroduplexes. The repair of a particular strand of the heteroduplex is inhibited by full methylation of the adenines in the GATC sequences of that strand. Thus, it appears that the E. coli mismatch repair system can act on newly synthesized DNA strands to remove replication errors involving the insertion or deletion of a single base.