Abstract
Gene duplication through cDNA synthesis by reverse transcriptase is believed to have played an important role in the diversification of genomes during evolution. Here, we demonstrate that a genomic DNA sequence can be duplicated in vivo as a result of template switching. When an inverted repeat (IR) structure was inserted in a site downstream from a ColE1 plasmid origin of DNA replication, transformation of Escherichia coli cells with this plasmid resulted in the production of a new DNA fragment encompassing the region from the origin to the center of the IR structure. The structure of this DNA molecule is composed of a long stem-loop formed by a single-stranded DNA, in which the loop is formed by the IR structure. The DNA fragment is designated slDNA, for stem-loop DNA. The experiments in this study suggest that during DNA replication, template switching at the stem-loop structure formed by the IR structure gives rise to slDNA utilizing the nascent DNA strand or the parental strand as a template. The mechanistic implications of slDNA synthesis, and its possible roles in genome evolution, are discussed.
Full text
PDF




Images in this article
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Beck E., Ludwig G., Auerswald E. A., Reiss B., Schaller H. Nucleotide sequence and exact localization of the neomycin phosphotransferase gene from transposon Tn5. Gene. 1982 Oct;19(3):327–336. doi: 10.1016/0378-1119(82)90023-3. [DOI] [PubMed] [Google Scholar]
- Birnboim H. C., Doly J. A rapid alkaline extraction procedure for screening recombinant plasmid DNA. Nucleic Acids Res. 1979 Nov 24;7(6):1513–1523. doi: 10.1093/nar/7.6.1513. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Dasgupta S., Masukata H., Tomizawa J. Multiple mechanisms for initiation of ColE1 DNA replication: DNA synthesis in the presence and absence of ribonuclease H. Cell. 1987 Dec 24;51(6):1113–1122. doi: 10.1016/0092-8674(87)90597-6. [DOI] [PubMed] [Google Scholar]
- Gilson E., Clément J. M., Brutlag D., Hofnung M. A family of dispersed repetitive extragenic palindromic DNA sequences in E. coli. EMBO J. 1984 Jun;3(6):1417–1421. doi: 10.1002/j.1460-2075.1984.tb01986.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gilson E., Perrin D., Hofnung M. DNA polymerase I and a protein complex bind specifically to E. coli palindromic unit highly repetitive DNA: implications for bacterial chromosome organization. Nucleic Acids Res. 1990 Jul 11;18(13):3941–3952. doi: 10.1093/nar/18.13.3941. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gilson E., Saurin W., Perrin D., Bachellier S., Hofnung M. Palindromic units are part of a new bacterial interspersed mosaic element (BIME). Nucleic Acids Res. 1991 Apr 11;19(7):1375–1383. doi: 10.1093/nar/19.7.1375. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Higgins C. F., Ames G. F., Barnes W. M., Clement J. M., Hofnung M. A novel intercistronic regulatory element of prokaryotic operons. Nature. 1982 Aug 19;298(5876):760–762. doi: 10.1038/298760a0. [DOI] [PubMed] [Google Scholar]
- Inouye M., Inouye S. Retroelements in bacteria. Trends Biochem Sci. 1991 Jan;16(1):18–21. doi: 10.1016/0968-0004(91)90010-s. [DOI] [PubMed] [Google Scholar]
- Inouye M., Inouye S. msDNA and bacterial reverse transcriptase. Annu Rev Microbiol. 1991;45:163–186. doi: 10.1146/annurev.mi.45.100191.001115. [DOI] [PubMed] [Google Scholar]
- Lampson B. C., Sun J., Hsu M. Y., Vallejo-Ramirez J., Inouye S., Inouye M. Reverse transcriptase in a clinical strain of Escherichia coli: production of branched RNA-linked msDNA. Science. 1989 Feb 24;243(4894 Pt 1):1033–1038. doi: 10.1126/science.2466332. [DOI] [PubMed] [Google Scholar]
- Lerner C. G., Inouye M. Low copy number plasmids for regulated low-level expression of cloned genes in Escherichia coli with blue/white insert screening capability. Nucleic Acids Res. 1990 Aug 11;18(15):4631–4631. doi: 10.1093/nar/18.15.4631. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Maxam A. M., Gilbert W. Sequencing end-labeled DNA with base-specific chemical cleavages. Methods Enzymol. 1980;65(1):499–560. doi: 10.1016/s0076-6879(80)65059-9. [DOI] [PubMed] [Google Scholar]
- Sanger F., Nicklen S., Coulson A. R. DNA sequencing with chain-terminating inhibitors. Proc Natl Acad Sci U S A. 1977 Dec;74(12):5463–5467. doi: 10.1073/pnas.74.12.5463. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Sinnett D., Richer C., Deragon J. M., Labuda D. Alu RNA secondary structure consists of two independent 7 SL RNA-like folding units. J Biol Chem. 1991 May 15;266(14):8675–8678. [PubMed] [Google Scholar]
- Tomizawa J. I., Ohmori H., Bird R. E. Origin of replication of colicin E1 plasmid DNA. Proc Natl Acad Sci U S A. 1977 May;74(5):1865–1869. doi: 10.1073/pnas.74.5.1865. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Vieira J., Messing J. The pUC plasmids, an M13mp7-derived system for insertion mutagenesis and sequencing with synthetic universal primers. Gene. 1982 Oct;19(3):259–268. doi: 10.1016/0378-1119(82)90015-4. [DOI] [PubMed] [Google Scholar]
- Weiner A. M., Deininger P. L., Efstratiadis A. Nonviral retroposons: genes, pseudogenes, and transposable elements generated by the reverse flow of genetic information. Annu Rev Biochem. 1986;55:631–661. doi: 10.1146/annurev.bi.55.070186.003215. [DOI] [PubMed] [Google Scholar]
- Yanisch-Perron C., Vieira J., Messing J. Improved M13 phage cloning vectors and host strains: nucleotide sequences of the M13mp18 and pUC19 vectors. Gene. 1985;33(1):103–119. doi: 10.1016/0378-1119(85)90120-9. [DOI] [PubMed] [Google Scholar]