Decoding the Lateral Expansion of Plant Stems

• Applicant: Professor Dr. Thomas Greb
• Subject Area: Plant Cell and Developmental Biology ; Developmental Biology ; Plant Genetics and Genomics
• Term: from 2014 to 2018
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 255845630

In contrast to animals in which tissue proliferation in adult individuals is often pathological and deleterious, plants have evolved an indefinite growth habit. Especially remarkable in this respect is the thickening of plant stems and roots, as this is a pure postembryonic growth process and the responsible group of stem cells, the cambium, is embedded in highly differentiated tissues. Consequently, lateral plant growth has to integrate and overcome physical constraints implied by surrounding tissues and induce a fundamental change in their properties. How participating tissues communicate to establish such a complex growth process is completely unknown. Here we will explore the process of lateral stem growth in the reference plant Arabidopsis thaliana as a paradigm for postembryonic growth processes. We will study cell behavior by profiling the transcriptomes of each single stem tissue before and after lateral growth initiation. Cell walls fix the position of plant cells relative to each other and their rigidity is essential for mechanical support of the plant body. Therefore, we will additionally investigate the role of cell wall modifications in the regulation of lateral plant growth and identify by use of forward genetics novel signaling cascades that translate cell wall states into changes in cellular dynamics. Together, these approaches will provide unprecedented insight into lateral stem growth, a process responsible for wood production and the accumulation of a large proportion of terrestrial biomass. Thereby, this project will systemically characterize the development of an underexplored but central plant organ and reveal fundamental concepts of growth processes in multicellular organisms.

• DFG Programme: Research Grants
• Major Instrumentation: Wachstumskammern
• Instrumentation Group: 4400 Pflanzenwuchskammern und -schränke, Klimaversuchsanlagen für Biologie und Medizin