The phage T4 uvs Y recombination protein stabilizes presynaptic filaments.
The bacteriophage T4 uvsY protein is required for efficient recombination in T4-infected Escherichia coli cells. Previous in vitro work has shown that the purified uvsY protein is an accessory protein; it stimulates homologous pairing catalyzed by the phage uvsX protein (a RecA-like recombinase) under certain conditions. We show here that this effect can be traced, at least in part, to a UvsY-dependent stabilization of uvsX protein-single-stranded DNA complexes. These presynaptic filaments are one of the early obligatory intermediates in the strand exchange reaction between homologous single- and double-stranded DNAs. The mechanism of filament stabilization seems to involve a slower loss of UvsX subunits. A model that accounts for the data is presented in which both recombination proteins are incorporated into the presynaptic filament.
Kodadek
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Department of Chemistry, University of Texas, Austin 78712.
Gan
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Stemke-Hale
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D000251:Adenosine Triphosphatases / Q000378:metabolism; D002845:Chromatography; D002852:Chromatography, Ion Exchange; D004268:DNA-Binding Proteins / Q000378:metabolism; D017886:Durapatite; D004926:Escherichia coli / Q000235:genetics* / Q000378:metabolism; D006882:Hydroxyapatites; D007700:Kinetics; D008565:Membrane Proteins / Q000378:metabolism; D008962:Models, Theoretical; D011995:Recombination, Genetic; D013604:T-Phages / Q000235:genetics* / Q000378:metabolism / Q000648:ultrastructure; D014764:Viral Proteins / Q000378:metabolism
D004268:DNA-Binding Proteins; D006882:Hydroxyapatites; D008565:Membrane Proteins; C092863:UvsX protein, Enterobacteria phage T4; C092864:UvsY protein, Enterobacteria phage T4; D014764:Viral Proteins; D017886:Durapatite; D000251:Adenosine Triphosphatases