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PubMed · 10884228

Three-dimensional structure of the Tn5 synaptic complex transposition intermediate.

D R Davies·I Y Goryshin·W S Reznikoff·I Rayment
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Abstract

Genomic evolution has been profoundly influenced by DNA transposition, a process whereby defined DNA segments move freely about the genome. Transposition is mediated by transposases, and similar events are catalyzed by retroviral integrases such as human immunodeficiency virus-1 (HIV-1) integrase. Understanding how these proteins interact with DNA is central to understanding the molecular basis of transposition. We report the three-dimensional structure of prokaryotic Tn5 transposase complexed with Tn5 transposon end DNA determined to 2.3 angstrom resolution. The molecular assembly is dimeric, where each double-stranded DNA molecule is bound by both protein subunits, orienting the transposon ends into the active sites. This structure provides a molecular framework for understanding many aspects of transposition, including the binding of transposon end DNA by one subunit and cleavage by a second, cleavage of two strands of DNA by a single active site via a hairpin intermediate, and strand transfer into target DNA.

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Amino Acid MotifsBinding SitesCatalysisCatalytic DomainCrystallizationCrystallography, X-RayDNADNA Transposable ElementsDimerizationManganeseMutationNucleic Acid ConformationPlasmidsProtein BindingProtein ConformationProtein FoldingProtein Structure, SecondaryProtein Structure, TertiaryTransposasesCommentJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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D R Davies, I Y Goryshin, W S Reznikoff, I Rayment. 2000-07-07. Three-dimensional structure of the Tn5 synaptic complex transposition intermediate.. https://doi.org/10.1126/science.289.5476.77

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