DEVELOPMENTAL STAGE-DEPENDENT VARIATION OF THE LEVELS OF GLOBULAR STORAGE PROTEIN AND ASPARTIC ENDOPROTEASE DURING RIPENING AND GERMINATION OF THEOBROMA CACAO L SEEDS

摘要

Polyclonal antibodies were raised against the purified large subunits of the aspartic endoprotease and the 7S globulin of cocoa seeds. The antibody against the large subunit of the 7S globulin was found to cross-react with all of the 7S globulin subunits, whereas the antiserum raised against the large subunit of the aspartic endoprotease did not recognize the small polypeptide of the enzyme. Both antibodies were used to comparatively investigate the developmental stage-dependent variations of the levels of both proteins during seed ripening and germination. The aspartic endoprotease and the globular storage protein were found to be coordinatively accumulated during seed development of two clones of Theobroma cacao L. (ICS 95 and KKM 4) differing in the time course of fruit ripening. Maximal levels of the aspartic endoprotease and the 7S globulin were reached between 110 and 130 days after tagging in the case of clone ICS 95, whereas the same amounts of both proteins were accumulated in the seeds of done KKM 4 already 90 days after tagging. During seed germination, the amounts of 7S globulin decreased after a lag phase of 7 days after imbibition, whereas the amount and the activity of the aspartic endoprotease remained constant.