FIG 1 .

Arrangement of GT genes and generation of the Δgt1-3 null mutant that spans this locus. Both alleles of the GT1, GT2, and GT3 genes (GT1, GT2, and GT3) are shown on two homologous chromosomes. The first homologous gene replacement employed the puromycin acetyltransferase (PAC) selectable marker to generate the +/Δgt1-3 heterozygous deletion mutant, and the second homologous gene replacement employed the hygromycin (HYG) selectable marker to generate the null mutant. During the second targeted gene replacement, a 40-kb linear amplicon arose originating from chromosome 29 (arrow marked with a circled numeral 1; 29-40k amplicon, black rectangle) and encompassing 14 open reading frames. Alternatively, the null mutant lacking the 29-40k amplicon could be generated using the modified protocol described in the text (arrow marked with circled numeral 2). (Modified from Fig. 1A of reference 16 with permission of the publisher.)