Entry Name Zeatin biosynthesis
Description Zeatin is a member of the cytokinin family, a class of phytohormones involved in various processes of growth and development in plants. Most abundant cytokinins are adenine-type, where the N6 position of adenine is substituted with an isoprenoid, such as in zeatin, or an aromatic side chain, such as in kinetin. Zeatin can be synthesized in two different pathways: the tRNA pathway and the AMP pathway. In the tRNA pathway zeatin is a recycled product of isopentenylated tRNAs. In the AMP pathway zeatin is synthesized from an isopentenyl donor, dimethylallyl diphosphate (DMAPP), and AMP, ADP, or ATP by isopentenyltransferases. After synthesis cytokinins can be glucosylated.
Class Metabolism; Metabolism of terpenoids and polyketides
Pathway map Ortholog table Other DBs Reaction R01122 delta2-isopentenyl-diphosphate:tRNA isopentenyltransferase
R02118 UDPglucose:zeatin O-beta-D-glucosyltransferase
R02119 UDP-D-xylose:zeatin O-beta-D-xylosyltransferase
R03133 O-acetyl-L-serine acetate-lyase (adding N6-substituted adenine)
R03726 S-adenosyl-L-methionine:N6-(delta2-isopentenyl)-adenine 3-(3-amino-3-carboxypropyl)-transferase
R04038 2-isopentenyl-diphosphate:AMP delta2-isopentenyltransferase
R05702 dihydrozeatin:NADP oxidoreductase
R05708 N6-dimethylallyladenine:(acceptor) oxidoreductase
R07260 UDP-glucose:cis-zeatin O-beta-D-glucosyltransferase
R08051 2-isopentenyl-diphosphate:ATP delta2-isopentenyltransferase
R08052 2-isopentenyl-diphosphate:ADP delta2-isopentenyltransferase
R08053 isopentenyladenosine-5'-triphosphate,NADPH---hemoprotein reductase:oxygen oxidoreductase (trans-zeatin-riboside-triphosphate-forming)
R08054 isopentenyladenosine-5'-diphosphate,NADPH---hemoprotein reductase:oxygen oxidoreductase (trans-zeatin-riboside-diphosphate-forming)
R08055 isopentenyladenosine-5'-monophosphate,NADPH---hemoprotein reductase:oxygen oxidoreductase (trans-zeatin-riboside-monophosphate-forming)
R08066 isopentenyladenosine,NADPH---hemoprotein reductase:oxygen oxidoreductase (trans-zeatin-riboside-forming)
R08068 isopentenyladenine,NADPH---hemoprotein reductase:oxygen oxidoreductase (trans-zeatin-forming)
Compound C00019 S-Adenosyl-L-methionine
C00235 Dimethylallyl diphosphate
C03423 O-beta-D-Glucosylzeatin
C04083 N6-(Delta2-Isopentenyl)-adenine
C04432 tRNA containing 6-isopentenyladenosine
C04713 N6-(delta2-Isopentenyl)-adenosine 5'-monophosphate
C15546 O-beta-D-Glucopyranosyl-cis-zeatin
C16424 Isopentenyladenosine-5'-triphosphate
C16426 Isopentenyladenosine-5'-diphosphate
C16428 trans-Zeatin riboside triphosphate
C16429 trans-Zeatin riboside diphosphate
C16430 trans-Zeatin riboside monophosphate
C16441 cis-Zeatin riboside monophosphate
C16443 trans-Zeatin-7-beta-D-glucoside
C16445 Dihydrozeatin riboside monophosphate
C16448 Dihydrozeatin-O-glucoside
Reference Authors Kasahara H, Takei K, Ueda N, Hishiyama S, Yamaya T, Kamiya Y, Yamaguchi S, Sakakibara H.
Title Distinct isoprenoid origins of cis- and trans-zeatin biosyntheses in Arabidopsis.
Journal Reference Authors Takei K, Sakakibara H, Sugiyama T.
Title Identification of genes encoding adenylate isopentenyltransferase, a cytokinin biosynthesis enzyme, in Arabidopsis thaliana.
Journal Reference Authors Kakimoto T.
Title Identification of plant cytokinin biosynthetic enzymes as dimethylallyl diphosphate:ATP/ADP isopentenyltransferases.
Journal Reference Authors Takei K, Yamaya T, Sakakibara H.
Title Arabidopsis CYP735A1 and CYP735A2 encode cytokinin hydroxylases that catalyze the biosynthesis of trans-Zeatin.
Journal Reference Authors Hou B, Lim EK, Higgins GS, Bowles DJ.
Title N-glucosylation of cytokinins by glycosyltransferases of Arabidopsis thaliana.
Journal Reference Authors Martin RC, Mok MC, Mok DW
Title Isolation of a cytokinin gene, ZOG1, encoding zeatin O-glucosyltransferase from Phaseolus lunatus.
Journal Reference Authors Martin RC, Mok MC, Mok DW
Title A gene encoding the cytokinin enzyme zeatin O-xylosyltransferase of Phaseolus vulgaris.
Journal Reference Authors Veach YK, Martin RC, Mok DW, Malbeck J, Vankova R, Mok MC
Title O-glucosylation of cis-zeatin in maize. Characterization of genes, enzymes, and endogenous cytokinins.
Journal Reference Authors Werner T, Motyka V, Laucou V, Smets R, Van Onckelen H, Schmulling T
Title Cytokinin-deficient transgenic Arabidopsis plants show multiple developmental alterations indicating opposite functions of cytokinins in the regulation of shoot and root meristem activity.
Journal Reference Authors Miyawaki K, Tarkowski P, Matsumoto-Kitano M, Kato T, Sato S, Tarkowska D, Tabata S, Sandberg G, Kakimoto T
Title Roles of Arabidopsis ATP/ADP isopentenyltransferases and tRNA isopentenyltransferases in cytokinin biosynthesis.
Journal Related rn00900 Terpenoid backbone biosynthesis
KO pathway LinkDB All DBs
