Nucleotide and deduced amino acid sequence of the 22-kilodalton cathepsin D inhibitor protein of potato (Solanum tuberosum L.).

Severa1 storage proteins of potato (Solanum tuberosum L.) tubers have been identified, including severa1 proteinase inhibitors such as proteinase inhibitor I and I1 and the 22-kD protein group (Melville and Ryan, 1972; Bryant et al., 1976; Suh et al., 1990). The 22-kD cathepsin D inhibitor protein of potatoes (PDI) has been purified and characterized (Mares et al., 1989). This glycosylated protein inhibits cathepsin D and trypsin activity and is homologous with the soybean trypsin inhibitor family (Mares et al., 1989). Recent studies showed that PDI transcripts accumulate in potato tubers, stems, roots,