Sequence and tissue-specific expression of a putative peroxidase gene from wheat (Triticum aestivum L.).

We have used a cDNA clone encoding a pathogen-induced putative wheat peroxidase to screen a genomic library of wheat (Triticum aestivum L. cv. Cheyenne) and isolated one positive clone, lambda POX1. Sequence analysis revealed that this clone contains a gene encoding a putative peroxidase with a calculated pI of 8.1 which exhibits 58% and 83% sequence identity to the amino acid sequence of the turnip (Brassica rapa) peroxidase and a pathogen-induced putative wheat peroxidase, respectively. The two introns in the wheat gene are at the same positions as introns in the peroxidase genes of tomato and horseradish. Results of S1-mapping experiments suggest that this gene is neither pathogen- nor wound-induced in leaves but is constitutively expressed in roots.