Description
trans-Zeatin is a cytokinin plant growth regulator with antioxidant and neuroprotective activities. It binds to the cytokinin receptor
Arabidopsis histidine kinase 3 (AHK3) with a K
D value of 1.3 nM.
trans-Zeatin increases chlorophyll levels in etiolated
Cucumus sativus cotyledons in a concentration-dependent manner. It increases callus growth and shoot formation in
N. tabacum calluses when used at concentrations of 5 and 50 μM.
trans-Zeatin (25-100 μM) reduces production of reactive oxygen species (ROS) induced by amyloid β (25-35) (Aβ25-35) in PC12 cells. It reduces scopolamine-induced spontaneous alternations in the Y-maze, indicating enhanced spatial memory, in mice when administered at doses of 1.5, 3, and 4.5 mg/kg per day.
Chemical Properties
white to light yellow crystal powder
Physical properties
Trans-zeatin is freely soluble in acetic acid and water.
Uses
Zeatin, purified from Zea mays, is a member of the cytokinin group of plant growth factors, the activity of which is attributed to its more stable trans form. Trans-Zeatin inhibits UVB-induced matrix metalloproteinase-1 expression via MAP kinase signaling in human skin fibroblasts. Trans-Zeatin is a potential agent for the management of skin photoaging.
Definition
Increased levels of cytokinins such as trans-zeatin, which are considered highly active, induced resistance against mainly (hemi)biotrophic pathogens in different plant species. In contrast, cis-zeatin is commonly regarded as a cytokinin exhibiting low or no activity [1].
Definition
ChEBI: The trans-isomer of zeatin.
General Description
trans-Zeatin contains a hydroxylated isoprenoid side chain.
Biochem/physiol Actions
Zeatin upon reduction forms zeatin O-glucoside, which is widely present in plants. It possesses transportation and storage functions, along with defence against zeatin oxidases.
Purification Methods
Purify zeatin by recrystallisation from EtOH or H2O. The UV has max at 207 and 275nm ( 1,400 and 14,650) in 0.1N aqueous HCl; 212 and 270nm ( 17,050 and 16,150) in aqueous buffer pH 7.2; 220 and 276nm ( 15,900 and 14,650) in 0.1N aqueous NaOH. The picrate has m 192-194o (from H2O) from which zeatin can be recovered by treatment with Dowex-1 x 8 (200-400 mesh, OH-form). [Letham et al. Aust J Chem 22 205 1969, Proc Chem Soc (London) 230 1964, Shaw & Wilson Proc Chem Soc (London) 231 1964.] It is a cell division factor (plant growth regulator) [Letham & Palni Ann Rev Plant Physiol 34 163 1983] and inhibits mitochondrial function [Miller Plant Physiol 69 1274 1982]. The commercially available trans -9-riboside derivative, [6025-53-2], M 351.4,is a cytokine which separates from aqueous AcOH with m 177-179o. It solubility in AcOH is ~5%. [McDonald & Morris Methods Enzymol 100 347 1985].
References
[1] Dominik K Gro?kinsky. “Cis- and trans-zeatin differentially modulate plant immunity.” Plant Signaling Behavior 8 7 (2013): e24798.
