α- amylase activity by GA3 - Dormancy
Of the enzymes required for the digestion of starch α-amylase appears immediately after the start of germination. It was found that if the embryo was removed no a-amylase appeared, however, if very low concentations of GA3 were added to the seed the production of digestive enzyme proceeds. The work over the last 30 years proved the fact that GA3 initiates action at transcriptional and translational levels. Not only activation of pre-existing m-RNAs coding for a-amylase but synthesis of m-RNA also takes place after the exposure of seeds to GA3.
Cytokinins and Cell Division
Cell division involves synthesis of new DNA, RNA and a host of cell proteins in interphase (cell cycle S1 and S2). All these events are promoted by cytokinins. Cell division also means synthesis of a number of enzymes that are needed for the synthesis of cell wall and middle lamella.