Linked Life Data

17669422

Source:http://linkedlifedata.com/resource/pubmed/id/17669422

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2007-8-24
pubmed:abstractText
The higher-order DNA-protein complex that carries out the chemical steps of phage Mu transposition is organized by bridging interactions among three DNA sites, the left (L) and right (R) ends of Mu, and an enhancer element (E), mediated by the transposase protein MuA. A subset of the six subunits of MuA associated with their cognate sub-sites at L and R communicate with the enhancer to trigger the stepwise assembly of the functional transpososome. The DNA follows a well-defined path within the transpososome, trapping five supercoil nodes comprising two E-R crossings, one E-L crossing and two L-R crossings. The enhancer is a critical DNA element in specifying the unique interwrapped topology of the three-site LER synapse. In this study, we used multiple strategies to characterize Mu end-enhancer interactions to extend, modify and refine those inferred from earlier analyses. Directed placement of transposase subunits at their cognate sub-sites at L and R, analysis of the protein composition of transpososomes thus obtained, and their characterization using topological methods define the following interactions. R1-E interaction is essential to promote transpososome assembly, R3-E interaction contributes to the native topology of the transpososome, and L1-E and R2-E interactions are not required for assembly. The data on L2-E and L3-E interactions are not unequivocal. If they do occur, either one is sufficient to support the assembly process. Our results are consistent with two R-E and perhaps one L-E, being responsible for the three DNA crossings between the enhancer and the left and right ends of Mu. A 3D representation of the interwrapped complex (IW) obtained by modeling is consistent with these results. The model reveals straightforward geometric and topological relationships between the IW complex and a more relaxed enhancer-independent V-form of the transpososome assembled under altered reaction conditions.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0022-2836
pubmed:author
pubmed:issnType
Print
pubmed:day
14
pubmed:volume
372
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
382-96
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
Interactions of phage Mu enhancer and termini that specify the assembly of a topologically unique interwrapped transpososome.
pubmed:affiliation
Section of Molecular Genetics and Microbiology and Institute of Cellular and Molecular Biology, University of Texas at Austin, Austin, TX 78712, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural