Fig. 4.

Detection of proteases in petal abscission zones (after ethylene treatment and in field-abscising samples) by in-gel protease assay on a 12% SDS-polyacrylamide gel. Samples were loaded without any protease inhibitor or with a cystein protease inhibitor (+E-64) or with a serine protease inhibitor (+PMSF). The ∼37 kDa cysteine protease induced after ethylene treatment and in naturally abscising samples can be seen as clearing in the gelatin containing gel. 0 h, 0 h control; 8hE, 8 h ethylene-treated abscission zone samples; 24hNAZ, 24 h natural abscission zone (field-abscising) samples.