The activity of adenylate cyclase (AC, EC 18.104.22.168) was studied in oat (Avena sativa L.) seedlings. The following conditions were optimal for AC activity: a substrate (Mg2+-ATP) concentration of 0.75 mM; a temperature of 20-25°C, and pH 7.5. AC activity was detected in all subcellular fractions. The highest activity was observed in the microsomal fraction. GTP, its nonhydrolyzable analogs, and forskolin substantially enhanced the AC activity, whereas extracellular Ca2+ had no effect. The AC is suggested to exist in plant tissues in a membrane-bound form. The endogenous cAMP level was shown to depend on seedling illumination: it was far lower in etiolated seedlings and those adapted to darkness. Red and far-red light affected the endogenous cAMP content, indicating the possible involvement of cAMP in the phytochrome signaling pathway.
|Number of pages||5|
|Journal||Russian Journal of Plant Physiology|
|Publication status||Published - Jul 2000|
Copyright 2004 Elsevier Science B.V., Amsterdam. All rights reserved.
- Adenylate cyclase activity
- Avena sativa