Research

Group of auxin transport (Head: Jan Petrášek)

Effect of NPA on auxin transportWe focus on the molecular mechanism of polar auxin transport and on the ways of its regulation.

Plant hormone auxin is a key regulator of many developmental processes in plants. It plays a major role in control of temporal and spatial aspects of plant growth and, as such, it co-ordinates plant development. In contrast to other plant growth regulators (plant hormones), in some tissues auxin molecules are transported to long distances through plant body and their transport is directional (polar).

Mechanism of the polar auxin transport is based on physical-chemical properties of auxin molecules and on their molecular forms inside and outside cells. It is a very complex and dynamic process with many levels of regulation. More…

Group of metabolism and physiological function of cytokinins (Head: Václav Motyka)

Working hypothesisWe are engaged in the research of cytokinins, i.e. plant hormones that regulate cell division and differentiation and thus efficiently control plant growth and development.

Cytokinins are naturally occurring phytohormones that act in concert with auxins to regulate cell division and differentiation and thus efficiently control plant growth and development. Transient enhancement of auxin in relation to cytokinin levels induces root formation while the opposite shift results in shoot formation. Re-establishment of the two hormone quantitative ratios (hormonal homeostasis) is essential for further development of induced events.

Endogenous levels of bioactive cytokinins and their mode of action in plants are regulated at different levels and by various mechanisms concerning biosynthesis, metabolic conversions, inactivation and degradation as well as signalling pathways and transport. More…

Group of the role of phytohormones in the interaction with environment (Head: Radka Vaňková)

Gradient of cytokinins under drought stressWe focus on the elucidation of plant defence mechanisms, with the aim to contribute to the development of effective strategies to enhance stress tolerance of plants.

Plants have evolved complex systems of defence against, and adaption to, the variable and often potentially damaging environmental conditions to which they are exposed during their growth and development. Due to their sessile character, plants need to respond very dynamically to various abiotic (drought, extreme temperatures, high light intensity) as well as biotic stresses (pest and pathogen attacks).

Drought belongs to the most frequent abiotic stresses. Plants cope with water stress by preferential protection of upper leaves and apex. Gradual degradation of macromolecules takes place in lower leaves, nutrients being transported to upper leaves. Plant hormones cytokinins increase the sink strength.

We found that stress induced polarization of tobacco plants has been mediated by the establishment of cytokinin gradient in favour of upper leaves. This gradient is during severe water deficit strengthened by the stimulation of cytokinin degradation by cytokinin oxidase/dehydrogenase (CKX) in lower leaves. More…

Analytical unit (Head: Petr Dobrev)

Metabolic profileThe analytical unit of our laboratory works on improving of existing and developing of new analytical procedures for purification, quantitation and metabolic profiling of plant hormones and some other bioactive substances of plant origin. More…

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