Gene and protein structures of Theobroma cacao NPR1. A. Diagram of TcNPR1 gene structure. Boxes with diagonal stripes represent exons. Diagonal lines represent introns. The arrow represents the start site of transcription. The sizes of the promoter region, coding and the 3'-untranslated (UTR) regions of TcNPR1 are indicated. B. Alignment of AtNPR1 and TcNPR1 proteins. Protein alignment was carried out by ClustalW. Residues blocked in black are identical in both sequences. Numbers refer to the amino acid position in AtNPR1 protein. BTB/POZ and ankyrin repeats domains are highlighted by dashed line box and solid line box, respectively. Two of the conserved cysteines (C82 and C216 in AtNPR1) are shown with grey triangles. The potential nuclear localization signal identified in Arabidopsis is underlined. Amino acids demonstrated to be critical for AtNPR1 nuclear translocation are indicated with black triangles. C. Schematic representation of predicted cis-acting regulatory DNA element in cacao TcNPR1 promoter region. A 1.1 kb DNA fragment upstream of start codon was analyzed by querying the PLACE and PlantCare databases. The colored blocks represent different cis-elements as indicated.