Phytosteroids

The Phytosteroid group is interested in the biological and immunological activities of brassinosteroids, plant and animal steroids and related compounds. Brassinosteroids are involved in control of many important physiological and developmental processes, but their concentrations in plants are extremely low (pg.g^-1 fresh weight). Progress in plant steroid chemistry and biology would not be possible without sensitive biological tests and specific methods for their detection in plant tissues. We have therefore established sensitive and specific method for brassinosteroid determination based on combined immunoaffinity chromatography (IAC) and HPLC/ELISA or UPLC/MS/MS, respectively. Series of polyclonal and monoclonal antibodies against steroids have been developed and used in ELISA tests for their quantification in body fluids (e.g. cow milk).

The role of vertebrate-type steroid hormones in plant metabolism is still not completely understood and their metabolic pathways and mechanisms of action in plant remain unclear. When applied to plants they affect various physiological processes including, for example, root and shoot growth, flowering, calus proliferation and embryo growth, pollen tube growth and sex expression. Such steroids have been isolated from various plant species, but a reliable and highly sensitive analytical method for their identification and determination is still lacking. Developing of such a method utilizing IAC with UPLC/MS/MS is currently one of the important aims of our group.

A few BRs demonstrate remarkable cytotoxicity in vitro in animal cell lines. Their activity could, at least partially, be related to brassinosteroid-steroid receptor interactions. As BRs are relatively recently discovered group of agents, their mechanism of action at the molecular level is still largely unknown. An important aim of our study is to determine whether natural BRs and their synthetic analogues can affect the viability, proliferation, differentiation and apoptosis in cancer cell lines. Such information could give us a better understanding of the mechanism of brassinosteroid action at the molecular level and provide potentially good candidates for the development of anticancer drugs.

Group Members
Jana Oklešťková
Radim Simerský
Lucie Rárová

Equippment and Materials