<p style="text-align: justify;">Maize line MON802 was produced by biolistic transformation with a mixture of DNAs from two plasmids, PV-ZMBK15 and PV-ZMGT03. Plasmid PV-ZMBK15 contained the synthetic <i>cry1Ab</i> gene regulated by the 35S promoter from cauliflower mosaic virus (CaMV) and the 3&#39;-polyadenylation signal from the <i>Agrobacterium tumefaciens</i> nopaline synthase (<i>nos</i>) gene.</p>

<p style="text-align: justify;">Plasmid PV-ZMGT03 contained both the CP4 EPSPS encoding gene from <i>A. tumefaciens</i> strain CP4 and the <i>goxv247</i> gene from <i>Ochrobactrum anthropi</i>, which encodes the enzyme glyphosate oxidoreductase. The expression of CP4 EPSPS was regulated via the CaMV 35S promoter and the HSP70 intron, while <i>gox</i> gene expression was under the control of the CaMV 35S promoter only. Both genes were terminated with sequences from the 3&#39;-polyadenylation signal from the <i>nos</i> gene from <i>A. tumefaciens</i>. Post-translational targeting of the CP4 EPSPS and glyphosate oxidoreductase enzymes to the chloroplast was accomplished by fusion of the 5&#39;-terminal coding sequences with chloroplast transit peptide DNA sequences from <i>Arabidopsis thaliana</i> EPSPS gene (CTP2) and from <i>A. thaliana</i> SSU1A gene (CTP1), respectively.</p>

<p style="text-align: justify;">Both plasmids also contained sequences encoding the enzyme neomycin phosphotransferase II (NPTII) from the Tn5 transposon of <i>Escherichia coli</i>, strain K12. Expression of the <i>neo</i> gene was regulated by a bacterial promoter and used as a selectable marker to identify bacteria transformed with recombinant plasmid DNAs, but is not functional in plants. The expression of CP4 EPSPS and glyphosate oxidoreductase activity were used as selectable traits to screen transformed plants for the presence of the <i>cry1Ab</i> gene and to confer resistance to glyphosate herbicides.</p>
