Tn7 transposition: target DNA recognition is mediated by multiple Tn7-encoded proteins in a purified in vitro system.
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.
Department of Biochemistry and Biophysics, George W. Hooper Foundation, University of California, San Francisco 94143.
R J
RJ
Bainton
K M
KM
Kubo
J N
JN
Feng
N L
NL
Craig
D000255:Adenosine Triphosphate / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics*; D001483:Base Sequence; D004251:DNA Transposable Elements; D004269:DNA, Bacterial / Q000235:genetics*; D004268:DNA-Binding Proteins / Q000235:genetics*; D066298:In Vitro Techniques; D046911:Macromolecular Substances; D008274:Magnesium / Q000378:metabolism; D008969:Molecular Sequence Data; D011994:Recombinant Proteins / Q000378:metabolism; D011995:Recombination, Genetic
D001426:Bacterial Proteins; D004251:DNA Transposable Elements; D004269:DNA, Bacterial; D004268:DNA-Binding Proteins; D046911:Macromolecular Substances; D011994:Recombinant Proteins; D000255:Adenosine Triphosphate; D008274:Magnesium