Creation of modular destination vectors via reverse BP clonase reaction. A, Combined genetic elements p35S (pEN-L4-2-R1), NLS-GFP (pEN-L1-NF-L2), and GFP (pEN-R2-F-L3), or p35S (pEN-L4-2-R1), NLS-DsRed (pEN-L1-NR-L2), and DsRed (pEN-R2-R-L3), or p35S (pEN-L4-2-R1), NLS-GFP (pEN-L1-NF-L2), and GUS (pEN-R2-S*-L3) were merged and introduced via a MultiSite LR clonase reaction into a destination vector (pK7m34GW) carrying the attR4-ccdB-attR3 Gateway cassette, yielding the expression clones pK7FNF2, pK7RNR2, and pK7S*NF2, respectively. B, Recombination of these clones with pDONR P4-P1R in a BP recombination reaction to restore the attR4-ccdB-attL1 Gateway cassette and to create modular destination vector series for promoter analysis. C, Recombination of the same expression clones with pDONR P4-P2 to restore the attR4-ccdB-attR2 Gateway cassette and to create another series of modular destination vectors for translational fusion with a genomic fragment including promoter and coding sequence. Box shape annotation is as indicated at the bottom of C. Abbreviations specify the following sequences: 1, pNOS; 2, pCaMV 35S; 6, tNOS; 7, tCaMV 35S; F, GFP; NF, NLS-GFP; NR, NLS-DsRed; R, DsRed; S*, GUS with stop codon; K, NPTII kanamycin resistance selectable marker.