Research Interests

Rhizobium-legume symbiosis was always in the focus of my research interest. First by its importance in the combined nitrogen-pool of the Earth through nitrogen fixation but mostly because of the exciting molecular communication and elaborated developmental programs of the bacterium and the plant partner. My research started with the identification of the Rhizobium nodulation genes whose products; the Nod factors induce root nodule formation in the host plant. Then I studied how Nod factors activate cell cycle in the differentiated plant cells and the mechanism of meristem formation and cell differentiation. We have identified the cell cycle switch CCS52 proteins that play roles in meristem maintenance, cell cycle exit and genome doublings and showed that growth and polyploidy of symbiotic cells by CCS52A is essential for nodule differentiation. Our recent studies discovered a remarkable, plant controlled differentiation process of the bacterium partner resulting in living, non-dividing, polyploid, elongated and branched nitrogen fixing bacteria. We have shown that the bacterium differentiation plant factors are nodule-specific peptides resembling antimicrobial peptides of the innate immunity that interact with the bacterial cell envelope and enter the cytosol. Our current studies aim at the identification of the bacterial targets and the mode of action of the plant peptides both in and beyond symbiosis.

Membership Type

International Member

Election Year


Primary Section

Section 25: Plant Biology