<p style="text-align: justify;">The MS1 and RF2 canola lines were created by <i>Agrobacterium</i>-mediated transformation in which the transfer-DNA (T-DNA) contained either the <i>barnase</i> or <i>barstar</i> genes from the common soil bacterium, <i>Bacillus amyloliquefaciens</i>, under the control of the PTA29 anther-specific promoter from <i>Nicotiana tabacum</i>. In addition, each T-DNA contained a copy of the <i>bar</i> gene from <i>S. hygroscopicus</i>, which encodes the PAT enzyme, and sequences encoding the enzyme neomycin phosphotransferase II (NPTII) from the Tn5 transposon of <i>Escherichia coli</i>, strain K12. Expression of the <i>bar</i> gene was regulated by the PSsuAra promoter from <i>Arabidopsis thaliana</i> and post-translational targeting of the gene product to the chloroplast organelles was accomplished by fusion of the 5&rsquo;-terminal coding sequence with the chloroplast transit peptide DNA sequence from <i>A. thaliana</i>. The expression of NPTII activity, under control of the nopaline synthase promoter from <i>A. tumefaciens</i>, was used as a selectable trait for screening transformed plants for the presence of the <i>barnase</i> and <i>barstar</i> genes, respectively.</p>
