title: Both cyclic-AMP and cyclic-GMP can act as regulators of the phenylpropanoid pathway in Arabidopsis thaliana seedlings.
abstract: Cyclic nucleotides (cAMP and cGMP) are important signaling molecules that control a range of cellular functions and modulate different reactions. It is known that under abiotic or biotic stress plant cells synthesize these nucleotides and that they also enhance the activity of the phenylpropanoid pathway. Wondering what is the relation between these two facts, we investigated how the exogenously applied membrane-permeable derivatives, 8-Br-cAMP or 8-Br-cGMP, which are believed to act as the original cyclic nucleotides, affect the expression of the genes for and the specific activity of three enzymes of the phenylpropanoid pathway in Arabidopsis thaliana seedlings. We found that the expression of the genes of phenylalanine ammonia-lyase (PAL2), 4-coumarate:coenzyme A ligase (4CL1) and chalcone synthase (CHS), and the specific activities of PAL (EC 4.3.1.5), 4CL (EC 6.2.1.12) and CHS (EC 2.3.1.74) were induced in the same way by either of these cyclic nucleotides used at 5 μM concentration. None of the possible cAMP and cGMP degradation products (AMP, GMP, adenosine or guanosine) evoked such effects. Expression of PAL1, 4CL2 and 4CL3 were practically not affected. Although the investigated nucleotides induced rapid expression of the aforementioned enzymes, they did not affect the level of anthocyanins within the same period. We discuss the effects exerted by the exogenously administered cyclic nucleotides, their relation with stress and the role which the phenylpropanoid pathways the cyclic nucleotides may play in plants.
authors.affiliation: Department of Plant Physiology, Poznań University of Life Sciences, Wołyńska 35, 60-637 Poznań, Poland. gospi@up.poznan.pl
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Pietrowska-Borek
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Nuc
mesh_terms: D000217:Acyltransferases / Q000235:genetics / Q000378:metabolism; D000222:Adaptation, Physiological / Q000235:genetics; D000872:Anthocyanins / Q000378:metabolism; D017360:Arabidopsis / Q000187:drug effects / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D003066:Coenzyme A Ligases / Q000235:genetics / Q000378:metabolism; D000242:Cyclic AMP / Q000378:metabolism* / Q000494:pharmacology; D006152:Cyclic GMP / Q000031:analogs & derivatives / Q000378:metabolism* / Q000494:pharmacology; D015870:Gene Expression; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D053858:Metabolic Networks and Pathways / Q000187:drug effects / Q000235:genetics; D010636:Phenols / Q000378:metabolism*; D010650:Phenylalanine Ammonia-Lyase / Q000235:genetics / Q000378:metabolism; D036226:Seedlings / Q000187:drug effects / Q000378:metabolism; D013312:Stress, Physiological / Q000235:genetics*
chemical_list: D000872:Anthocyanins; D029681:Arabidopsis Proteins; D010636:Phenols; C016276:8-bromocyclic GMP; D000242:Cyclic AMP; D000217:Acyltransferases; C020141:flavanone synthetase; D010650:Phenylalanine Ammonia-Lyase; D003066:Coenzyme A Ligases; D006152:Cyclic GMP
keywords: 4-Coumarate:coenzyme A ligase; 4-coumarate:coenzyme A ligase; 4CL; Adenosine 3′,5′-cyclic monophosphate; Arabidopsis thaliana; CH; Chalcone synthase; Guanosine 3′,5′-cyclic monophosphate; PAL; Phenylalanine ammonia-lyase; adenosine 3′,5′-cyclic monophosphate; cAMP; cGMP; cNMP; chalcone synthase; guanosine 3′,5′-cyclic monophosphate; nucleoside 3′,5′-cyclic monophosphate; phenylalanine ammonia-lyase