Tn7 transposition: target DNA recognition is mediated by multiple Tn7-encoded proteins in a purified in vitro system

Cell. 1993 Mar 26;72(6):931-43. doi: 10.1016/0092-8674(93)90581-a.


We have reconstituted the transposition of the bacterial transposon Tn7 into its specific insertion site attTn7 with four purified Tn7-encoded proteins, TnsA+TnsB+TnsC+TnsD, and ATP. TnsA+TnsB+TnsC form a "core" recombination machine that recognizes the transposon ends and executes DNA breakage and joining; TnsD specifically recognizes attTn7. TnsA+TnsB+TnsC are specifically targeted to attTn7 through the TnsD-dependent interaction of TnsC, a nonspecific DNA-binding protein, with attTn7. Recombination appears to be activated by the assembly of a nucleoprotein complex containing the DNA substrates and Tns proteins. We suggest that TnsC plays a central role in communication between the transposon and the target DNA, particularly in directing insertion away from DNAs already containing a copy of Tn7.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adenosine Triphosphate / metabolism
  • Bacterial Proteins / genetics*
  • Base Sequence
  • DNA Transposable Elements*
  • DNA, Bacterial / genetics*
  • DNA-Binding Proteins / genetics*
  • In Vitro Techniques
  • Macromolecular Substances
  • Magnesium / metabolism
  • Molecular Sequence Data
  • Recombinant Proteins / metabolism
  • Recombination, Genetic*


  • Bacterial Proteins
  • DNA Transposable Elements
  • DNA, Bacterial
  • DNA-Binding Proteins
  • Macromolecular Substances
  • Recombinant Proteins
  • Adenosine Triphosphate
  • Magnesium