In vitro transposition of minute Mos1 transposons. (a) Diagrammatic representation of the transposition assay. The minute Mos1 (mini-Mos1) is represented by a double arrow in black. ITR3pA3 and pDONR221-CmR- were incubated for 1 hour with 80 nM of purified MOS1. The resulting plasmids were then transferred into DH5α E.coli and plated on kanamycin. Twenty clones were then sequenced, five of which corresponded to true transpositions. (b) Nucleic acid sequences of the five mini-Mos1 integration sites in the ccd B- gene. Sequences were obtained from plasmids conferring a ccd B toxin survival. The TA dinucleotides duplicated at the target site are shown in bold, the outer ends of the ITR are in italics and the transposon sequence is indicated by"/cloneX/".