This reaction is the rate-limiting step in cytokinin biosynthesis. DMADP and HMBDP used in cytokinin biosynthesis are produced by the methylerythritol phosphate. Cytokinins 1. LECTURE OUTLINE CYTOKININS Cytokinins Discovery Chemical Structure Biosynthesis Transport Signaling Functions Auxin controls local cytokinin biosynthesis in the nodal stem in apical dominance. Tanaka M(1), Takei K, Kojima M, Sakakibara H, Mori H. Auxin regulation of cytokinin biosynthesis in Arabidopsis thaliana: A factor of potential importance for auxin–cytokinin-regulated development CYTOKININS: BIOSYNTHESIS, METABOLISM AND PERCEPTION. D. K. Cytokinin biosynthesis in a cell-free system from cytokinin-autotrophic tobacco tissue cultures. cytokinin biosynthesis in Agrobacterium tumefaciens by plant phenolics. Mol. Plant Microbe Interact. 1:235–42. Cytokinins: Activity, Biosynthesis, and Translocation Download PPT; Figure 2. Cytokinin. Cytokinin biosynthesis also was examined in wild-type Arabidopsis plants after incubation on 2 H 2 O/[2 H 6]iPA-double tracer. Direct cytokinin biosynthesis measurements in Arabidopsis thaliana have shown that auxin can rapidly downregulate cytokinin biosynthesis. PPT Slides of All Figures; Hormonal Signaling II: Cytokinin and Ethylene Cytokinin 1) overview: Zeatin (a purine derivative) is most abundant natural cytokinin, discovered as a DNA breakdown. INTRODUCTION. Auxin and cytokinin play fairly important roles in many aspects of plant growth and development. The interaction between auxin and cytokinin.