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Implications of structures of synaptic tetramers of gamma delta resolvase for the mechanism of recombination.

ABSTRACT: The structures of two mutants of the site-specific recombinase, gammadelta resolvase, that form activated tetramers have been determined. One, at 3.5-A resolution, forms a synaptic intermediate of resolvase that is covalently linked to two cleaved DNAs, whereas the other is of an unliganded structure determined at 2.1-A resolution. Comparisons of the four known tetrameric resolvase structures show that the subunits interact through the formation of a common core of four helices. The N-terminal halves of these helices superimpose well on each other, whereas the orientations of their C termini are more variable. The catalytic domains of resolvase in the unliganded structure are arranged asymmetrically, demonstrating that their positions can move substantially while preserving the four-helix core that forms the tetramer. These results suggest that the precleavage synaptic tetramer of gammadelta resolvase, whose structure is not known, may be formed by a similar four-helix core, but differ in the relative orientations of its catalytic and DNA-binding domains.

SUBMITTER: Kamtekar S

PROVIDER: S-EPMC1483221 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Molecular Mechanism of V(D)J Recombination from Synaptic RAG1-RAG2 Complex Structures.

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LIMES Gamma Delta Data Access Commitee

Project description:Data Access Committee EGAC00001003406

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