An intermediate biomolecule to which donor DNA and target DNA covalently attatch during the migration of some DNA transposons.

The cointegrate forms during the process of transposition, where a small piece of DNA (called a transposon) at one site in a genome or a plasmid makes a copy of itself at a random other site, sometimes removing itself from the first site and sometimes not. The structure is composed of the first site and the new site attached together while the transposon is copying.

From the BioTech Dictionary at http://biotech.icmb.utexas.edu/. For further information see the BioTech homenode.