A defined system for the DNA strand-transfer reaction at the initiation of bacteriophage Mu transposition: protein and DNA substrate requirements.
AUTOR(ES)
Craigie, R
RESUMO
An early step in the transposition of bacteriophage Mu DNA in vitro is a DNA strand-transfer reaction that generates an intermediate DNA structure in which the Mu donor DNA and the target DNA are covalently joined. DNA replication, initiated at the DNA forks in this intermediate, generates a cointegrate product; simple insert products can also be formed from the same intermediate by degradation of a specific segment of the structure, followed by gap repair. This DNA strand-transfer reaction requires ATP, magnesium, the Mu A and Mu B proteins, and a factor supplied by an Escherichia coli cell extract. We have now shown that the host protein factor requirement can be satisfied by purified protein HU. The defined system has been used to determine the DNA substrate requirements for the reaction. The reaction requires the two Mu ends, located on the same DNA molecule, in the same relative orientation to one another as in the phage Mu genome. To participate in the strand-transfer reaction efficiently the mini-Mu plasmid, used as the transposon donor, must be supercoiled; the target DNA molecule may be supercoiled, relaxed circular, or linear.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=391374Documentos Relacionados
- A novel assay for the DNA strand-transfer reaction of HIV-1 integrase.
- Sensitive homologous recombination strand-transfer assay: partial purification of a Drosophila melanogaster enzyme and detection of sequence effects on the strand-transfer activity of RecA protein.
- DNA Strand-Transfer Activity in Pea (Pisum sativum L.) Chloroplasts.
- ClpX protein of Escherichia coli activates bacteriophage Mu transposase in the strand transfer complex for initiation of Mu DNA synthesis.
- Multiple roles for divalent metal ions in DNA transposition: distinct stages of Tn10 transposition have different Mg2+ requirements.