Protoplasts isolated from aleurone layers of wild oat (Avena fatua L.) exhibit the classic response to gibberellic acid.

Viable, long-lived, gibberellic acid (GA3)-responsive protoplasts have, for the first time, been isolated from aleurone layers of mature wild oat (Avena fatua L.) grain. More than 90% of the cells of aleurone layers are recovered as protoplasts, and these respond to treatment with GA3 in essentially the same manner as the tissue from which they were derived. Protoplasts become vacuolate during incubation in vitro and, although not dependent upon GA3, vacuolation is markedly stimulated by the hormone. Amylase and ribonuclease (RNase) are produced and secreted only in the presence of GA3 and only after lag periods of 3 d and 4 d respectively. The amounts of amylase produced and secreted are proportional to GA3 concentrations as low as 1.61·10(-13) M. With increasing concentrations of mannitol in the culture medium both vacuolation and the GA3-induced production and secretion of enzymes are inhibited progressively, the latter being precluded by 0.6 M to 0.7 M mannitol.