Group of auxin transport (Head: Eva Zažímalová)

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).

Plant development as well as their interactions with the environment are regulated by plant hormones. Hormones mediate both fast responses (e.g. stomata closure during water deficit) and long-term adaptations, associated with modulation of growth and development. The actual plant response depends on the stress severity and duration. Apart of the stress hormones, e.g. abscisic acid, an important role is played also by cytokinins and auxins. The aim of our work has been characterization of the role of individual plant hormones as well as their cross-talk in the response to abiotic and biotic stresses.

Group of mathematical modelling (Head: Klára Hoyerová)

Scheme of auxin transport processesOur laboratory uses mathematical modelling approach to unravel regulatory mechanisms of polar auxin flow in plants.

Nowadays, mathematical modelling is used as a tool for studying auxin transport more and more often. Present models are sometimes excessively simplified and/or do not reflect the structure of the real system properly. We have focused on construction of a detailed model of auxin transport mechanisms in plant cells using experimental data to analyse particular transport mechanism separately (an analytical-synthetic approach). These data include measurements of accumulation kinetics of radiolabeled auxins in cell suspensions and HPLC analysis of radiolabeled auxin metabolism, which has both provided valuable information about auxin transport properties at cellular level. 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…