Document Type
Article
Publication Date
7-21-1998
Source Publication
Proceedings of the National Academy of Sciences of the United States of America
Abstract
Transposition of the maize Suppressor-mutator (Spm) transposon requires two element-encoded proteins, TnpA and TnpD. Although there are multiple TnpA binding sites near each element end, binding of TnpA to DNA is not cooperative, and the binding affinity is not markedly affected by the number of binding sites per DNA fragment. However, intermolecular complexes form cooperatively between DNA fragments with three or more TnpA binding sites. TnpD, itself not a sequence-specific DNA-binding protein, binds to TnpA and stabilizes the TnpA-DNA complex. The high redundancy of TnpA binding sites at both element ends and the protein-protein interactions between DNA-bound TnpA complexes and between these and TnpD imply a concerted transition of the element from a linear to a protein crosslinked transposition complex within a very narrow protein concentration range.
Comments
Originally published in Proceedings of the National Academy of Sciences of the United States of America, Volume 95, No. 15 (July 1998).
The journal of the article is available at www.pnas.org.
Ramesh Raina, Michael Schläppi, and Nina Fedoroff are also affiliated with the Carnegie Institution of Washington.