Complete sequence of the binary vector pBI121 and its application in cloning T-DNA insertion from transgenic plants

The widely used expression vector pBI121 for plant transformation was reconstructed, and the complete sequence of 14758 bp is now available (accession number AF485783). The T-DNA region (6193 bp) contains the right border, expression cassettes for a neomycin phosphotransferase II (NPTII) selection marker and a beta-glucuronidase (GUS) reporter gene, and the left border. The non-T-DNA region (8565 bp) was constructed according to the Bin 19 vector. We applied the vector information to clone the plant/T-DNA junction region from three independent transgenic tobacco plants. Knowledge of the complete sequence of this vector will be useful for an accurate description of vector size, determination of the integrity of T-DNA, identification of independent lines, the locus where it is inserted, the T-DNA copy number in those stable transformants, or construction of a smaller vector. In addition, the complete sequence (5667 bp) of the transient expression vector pBI221 (accession number AF502128) carrying the ampicillin resistance and gus reporter genes is also reported.