Isolation of genomic DNA containing a cytosolic ascorbate peroxidase gene (ApxSC) from the strawberry (Fragaria x ananassa)

We isolated a genomic DNA harboring a cytosolic ascorbate peroxidase gene (ApxSC) from a genomic library of the strawberry (Fragaria x ananassa). Restriction mapping and sequence analyses showed that the DNA is composed of 2.5 kb of the full-length ApxSC gene, 3.7 kb of the 5'-upstream region, and 0.5 kb of the 3'-downstream region. The ApxSC genomic DNA contains 10 exons and 9 introns, which is similar to the structure of pea ApxI. A primer extension analysis suggested that the transcription of ApxSC gene was started at three s tart sites with different degrees. The promoter region of ApxSC gene contains a sequence or structure distinct from other reported plant ascorbate peroxidase genes, though with several known functional elements such as a TATA box