CHANGES IN DISTRIBUTION OF CHLOROPLAST ADENYLATE KINASE ISOFORMS DURING FLORAL INDUCTION

In the short day plant Chenopodium rubrum and the long day plant Nicot iana tabacum cv. Havana 425, adenylate kinase (EC 2.7.4.3) occurs as a family of isoforms, with at least two members localized in the chloro plast representing the main isoforms. In this work, isoforms were sepa rated by anion exchange chromatography and relative isoform activities were compared between vegetative plants and plants induced to floweri ng. In both species examined, a light regime leading to floral inducti on resulted in a significant decrease in the activity of one chloropla st isoform. This decrease modified considerably the relative distribut ion of isoform activities, especially that between the two chloroplast activities.