Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: July 15, 2000
Publication Date: N/A
Technical Abstract: Polyclonal antibodies were used in Western blot analysis to determine the relative amounts of Kunitz trypsin inhibitor in several soybean cultivars. Two accessions (P.I. 157440 and P.I. 196168) contained extremely low amounts of Kunitz trypsin inhibitor. Non-denaturing polyacrylamide enzyme activity gels indicated that soybean seeds contained at least five distinct tzones of trypsin inhibitor activity. However, P.I. 157440 and P.I. 196168 contained only four zones. Northern blot analysis revealed that P.I. 198168 expressed very low amounts of the mRNA encoding the major trypsin inhibitor protein. The gene encoding the major Kunitz trypsin inhibitor from P.I. 198168 was isolated by PCR. DNA sequence analysis indicated that the Kunitz trypsin inhibitor gene from P.I. 198168 had mutations in the coding region resulting in premature termination of the translation product. Immunocytochemical localization studies indicated that Kunitz trypsin inhibitor was predominantly localized in protein bodies and cell walls in soybean cultivar 'Amsoy 71'. Cell walls of the seed coat were also intensely labeled. Similar localization of Kunitz trypsin inhibitor was found in P.I. 198168, but the overall intensity of labeling was considerably lower.