EFFECT OF ANOXIA ON GIBBERELLIC ACID-INDUCED PROTEASE AND BETA-AMYLASE PROCESSING IN BARLEY-SEEDS

In barley seeds beta-amylase is synthesized during the development of the grain, where it accumulates bound to starch granules. As germinati on proceeds, beta-amylase is released through proteolytic processing l eading to a free form of the enzyme having a 5 kD lower molecular weig ht. Under anoxia, barley seeds are unable to germinate and both alpha- amylase synthesis and beta-amylase processing are inhibited. We report here data on the effects of anoxia on the induction of the protease r esponsible for the release of beta-amylase in barley seeds. The result s show that barley seeds kept under anoxia fail to produce the endopro tease involved in the processing of beta-amylase. This is likely the c onsequence of the lack of response of-barley seeds to GA(3) under anox ic conditions.