Two-step regulation of algal adenylyl cyclase activity by phytochrome in the lichen Evernia prunastri

Adenylyl cyclase activity of Evernia prunastri thalli is enhancedby red light pulses in a two-step way: a very rapid increaseof activity after the first 5 min of red light, which is notinhibited by cycloheximide, and a slow enhancement followingsuccessive red light pulses at the beginning of each 30 minincubation. The last response is completely reversed by far-redfollowing red light and inhibited by cycloheximide. Key words: Evernia prunastri, adenylyl cyclase, cyclic AMP, phytochrome