Replacement of AtSTM exon 1 by in-frame fusion of GAPc2ox1. A: Schematic representation of the strategy used to generate the GAPc2ox1 cassette from pNosTerFRT-neo (plus GAPc2ox1) plasmid and target it into the AtSTM locus (captured in pBlueAtSTM17) by in-frame substitution of exon 1 sequences. B: FIGE gel results of Pme I and EcoR V digested pSTM17::GAPc2ox1 from two independent recombination events (lanes 2 and 3), clearly showing the increased size of the linearised construct (Pme I digest) and the additional fragment (Eco RV digest) due to the recombination of the GAPc2ox1 cassette. Lane 1 shows the control result with the original pBlueAtSTM17. M1 = 1 kb ladder (New Endgland Biolabs); M2 = High Molecular Weight Marker (Invitrogen).