Figure 2.

Genomic Structure of T-DNA Insertion Alleles.

(A) atmdr1-1 and atmdr1-2.

(B) atpgp1.

Rectangles represent the exons and lines represent the untranslated regions, including introns of the two MDR-like genes. T-DNAs, represented by triangles, are not drawn to scale. Arrowheads indicate primers used to screen for the mutants. RNA gel blots provide evidence that the mutations severely or completely block expression. Fifty micrograms (A) or 30 μg (B) of total RNA from either Wassilewskija or mutant seedlings was subjected to electrophoresis, blotted, and probed as indicated. WT, wild type.