Model of cytokinin metabolism in wheat (Triticum aestivum L.) and identification of targets for pharmacological modulation of CKX to enhance grain productivity and stress tolerance

DOI: https://doi.org/10.7124/FEEO.v38.1818
Keywords: cytokinin oxidase, TaCKX, wheat, CKX

Abstract

Aim. To develop a model of cytokinin metabolism in Triticum aestivum L. with identification of key pharmacological intervention points and substantiation of strategies to enhance productivity and stress tolerance through inhibition of cytokinin oxidase/dehydrogenase (CKX) enzymes. Methods. Systematic literature analysis, meta-analysis of inhibitor efficiency, conceptual modeling of the metabolic network, molecular docking (AutoDock Vina 1.2) of F-INCYDE and INCYDE to the structure of AtCKX2 (PDB: 1W5O), and analysis of application timing according to the BBCH scale. Results. A model of cytokinin metabolism was developed, including biosynthesis, transport/reception, and degradation. Four key intervention points were identified. The TaCKX gene family was shown to comprise multiple functional members with tissue-specific expression. F-INCYDE demonstrated higher binding affinity to AtCKX2 (ΔG = –8.4 kcal/mol) compared to INCYDE (ΔG = –7.9 kcal/mol). ZOGT was identified as a parallel target explaining the limited efficacy of INCYDE. Optimal application stages were determined (BBCH 31–39, 55–65, 71–77). Conclusions. Dual inhibition of CKX and ZOGT represents a promising strategy for regulating cytokinin homeostasis in wheat and requires further experimental validation.

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