Mechanics of frameshift mutagenesis in bacteriophage T4: role of chromosome tips.
نویسندگان
چکیده
In contrast to observations in bacteria and fungi, frameshift mutations in bacteriophage T4 do not arise during genetic recombination. Nascent mutants, captured in the heterozygous condition, exhibit properties which indicate that the new lesions are located at the extreme tips of the chromosomes, and are segregated by a combination of recombination and replication.
منابع مشابه
The specificity of topoisomerase-mediated DNA cleavage defines acridine-induced frameshift specificity within a hotspot in bacteriophage T4.
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Acridine-induced frameshift mutagenesis in bacteriophage T4 has been shown to be dependent on T4 topoisomerase. In the absence of a functional T4 topoisomerase, in vivo acridine-induced mutagenesis is reduced to background levels. Further, the in vivo sites of acridine-induced deletions and duplications correlate precisely with in vitro sites of acridine-induced T4 topoisomerase cleavage. These...
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عنوان ژورنال:
- Proceedings of the National Academy of Sciences of the United States of America
دوره 65 3 شماره
صفحات -
تاریخ انتشار 1970