The Weijers group focuses on studying the mechanisms underlying multicellular development in plants. Multicellularity evolved more than once, and independently in the plant and animal kingdoms. How did each kingdom meet the challenges associated with multicellular development? How are different cell types specified? How are decisions of individual cells guided by supracellular information, such as polarity axes? How to key regulatory proteins control these processes? And how has the evolution of fundamental mechanisms controlling cellular shape, fate and behavior, contributed to the evolution of diverse plant morphologies?
We study these questions in relatively simple models, such as the embryos of the flowering plant Arabidopsis thaliana, in the liverwort Marchantia polymorpha, the fern Ceratopteris richardii, and in close algal relatives to land plants (Streptophyte algae). Our studies focus on the control of multicellular development at transcriptional level, as well as its implementation through cellular reorganization, and an area of focus is the control of transcription triggered by the plant hormone auxin. As a consequence, projects in the team span a relatively broad range of methodological approaches, but converge on the question of how multicellular development is controlled in plants.