Comparative Analysis of the Biosynthesis of Isoprenoid and Aromatic Cytokinins

• Published in: Doklady. Biochemistry and biophysics Vol. 488; no. 1; pp. 346 - 349
• Main Authors: Oslovsky, V. E., Savelieva, E. M., Drenichev, M. S., Romanov, G. A., Mikhailov, S. N.
• Format: Journal Article
• Language: English
• Published: Moscow Pleiades Publishing 01.09.2019; Springer Nature B.V
• Subjects: Arabidopsis - metabolism; Biochemistry; Biological and Medical Physics; Biomedical and Life Sciences; Biophysics; Biosynthesis; Comparative analysis; Cytokinins; Isopentenyladenosine - biosynthesis; Life Sciences; Molecular Biology; Nucleosides; Nucleotides; Ribose; Terpenes - metabolism
• ISSN: 1607-6729; 1608-3091
• DOI: 10.1134/S1607672919050156

To compare the biosynthesis pathways of aromatic and isoprenoid cytokinins, a series of nucleoside derivatives of natural cytokinins was synthesized and their cytokinin activity was determined in a test system based on the model plant Arabidopsis thaliana . Cytokinin nucleosides are known to lack the hormonal activity until cleaving the ribose moiety at the position 9. Our experiments have shown that both ribo- and 5'-deoxyribo derivatives of N 6 -isopentenyladenine were able to turn into active cytokinins in planta exhibiting cytokinin activity. By contrast, 5'-deoxy nucleosides of aromatic cytokinins did not show similar activity. Since 5'-deoxy nucleosides cannot phosphorylate in vivo, the direct pathway of active cytokinin formation by cleavage of nucleotides is blocked here. The detected activity in 5'-deoxy nucleosides of isoprenoid cytokinins and the lack of the activity in 5'-deoxy nucleosides of aromatic cytokinins indicates the difference in the biosynthesis of these compounds.