Figure 1.

Phylogenetic Tree and Structural Motifs for the NPR1 Protein Family in Arabidopsis.

(A) Phylogenetic tree for the NPR1 protein family. Arabidopsis Genome Initiative numbers are as follows: NPR1, At1g64280; BOP1, At3g57130; and BOP2, At2g41370.

(B) Conserved structural motifs in NPR1-like proteins. BTB/POZ and ankyrin motifs are represented by boxes marked BTB and ANK, respectively. Cys1 and Cys2 indicate conserved Cys residues that mediate redox control of NPR1 oligomerization (Cys-82 and Cys-262, respectively) (Mou et al., 2003).

(C) Alignment of the predicted BTB/POZ domains for NPR1-like proteins. The asterisk indicates Cys-82 in NPR1, which mediates redox control.

(D) Alignment of the predicted ankyrin repeats for NPR1-like proteins.