A GENE ENCODING A MAJOR KUNITZ PROTEINASE-INHIBITOR OF STORAGE ORGANSOF WINGED BEAN IS ALSO EXPRESSED IN THE PHLOEM OF STEMS

Winged bean Kunitz chymotrypsin inhibitor (WCI) accumulates abundantly in seeds and tuberous roots, and small amounts of the WCI protein and mRNA can also be detected in stems. In this study, we analyzed the lo calization of the WCI protein in stems of winged bean. The results dem onstrated that the WCI protein was localized in sieve tubes. Furthermo re, we showed that the 5' region of the WCI-3b gene, which exhibited s trong transcriptional activity in developing seeds, also promoted tran scription of a reporter gene in the phloem of stems of transgenic toba cco.