Quasi-palindromic sequences: a model for template-switch mutagenesis avoidance and stimulation
نویسنده
چکیده
vi1An Introduction1.1DNA Replication11.1.2 Leading and Lagging Strands41.1.3 Interference61.2Secondary Structures91.2.2 Quasi-palindromes101.2.3 Quasi-palindrome Mutational Reporters12References17 2Materials and Methods2.1Growth Medium212.2Strain Construction212.3Mutational Rate Determination222.4Sequence Determination23References26 3Exonucleases function to abort premutagenic template-switch events3.1Background273.1.2 Single stranded binding proteins283.1.3 Exonucleases303.2Results313.3Discussion38References43 45-azacytidine stimulates template-switch mutagenesis dependent on cytosinemethyl-transferase4.1Background464.1.2 DNA methylation464.2Results484.3Discussion53References55 5Conclusions and Future Work5.1Conclusions565.2Future Direction57
منابع مشابه
Cis and trans-acting effects on a mutational hotspot involving a replication template switch.
A natural mutational hotspot in the thyA gene of Escherichia coli accounts for over half of the mutations that inactivate this gene, which can be selected by resistance to the antibiotic trimethoprim. This T to A transversion, at base 131 of the coding sequence, occurs within a 17 bp quasi-palindromic sequence. To clarify the mechanism of mutagenesis, we examine here cis and trans-acting factor...
متن کاملDNA sequence effects on single base deletions arising during DNA polymerization in vitro by Escherichia coli Klenow fragment polymerase.
Most single base deletions detected after DNA polymerization in vitro directed by either Escherichia coli DNA polymerase I or its Klenow fragment are opposite Pu in the template. The most frequent mutations were previously found to be associated with the consensus template context 5'-PyTPu-3'. In this study, the predictive power of the consensus sequence on single base deletion frequencies was ...
متن کاملStructural intermediates of deletion mutagenesis: a role for palindromic DNA.
A model is presented for deletion mutations whose formation is mediated by palindromic and quasipalindromic DNA sequences. It proposes that the self-complementarity of palindromes allows the formation of DNA secondary structures that serve as deletion intermediates. The structures juxtapose the end points of the deletion and thus direct deletion specificity. While misaligned DNA intermediates t...
متن کاملAzidothymidine and other chain terminators are mutagenic for template-switch-generated genetic mutations.
The accumulation of mutations causes cell lethality and can lead to carcinogenesis. An important class of mutations, which are associated with mutational hotspots in many organisms, are those that arise by nascent strand misalignment and template-switching at the site of short repetitive sequences in DNA. Mutagens that strongly and specifically affect this class, which is mechanistically distin...
متن کاملDetection of template strand switching during initiation and termination of DNA replication of porcine circovirus.
Nucleotide substitution mutagenesis was conducted to investigate the importance of the inverted repeats (palindrome) at the origin of DNA replication (Ori) of porcine circovirus type 1 (PCV1). Viral genomes with engineered mutations on either arm or both arms of the palindrome were not impaired in protein synthesis and yielded infectious progeny viruses with restored or new palindromes. Thus, a...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2015