Plant meristems are major determinants of plant architecture, plant diversification and acclimation to environmental stresses. Moreover, meristems are fundamentally important for the productivity of crop plants as they directly determine yield.
Work in the model plant Arabidopsis revealed that meristems are organized by stem cell niches consisting of rarely dividing organizing cells, which are surrounded by stem cells. Stem cell niches in this species are regulated by feedback loops of stem cell controlling transcription factors and secreted ligands that are perceived by receptor kinases.
Compared to Arabidopsis, the shoot and root architectures of grasses (cereals) including the economically important crops maize, wheat, rice and barley are more complex. Grasses generate large vegetative meristems, produce additional organs like seminal and crown roots as well as highly complex inflorescence meristems with meristem types absent in eudicots. Mutations in genes controlling grass meristem functions have played key roles during crop domestication. Despite their economic importance, our understanding of meristem development and the organization of cereal stem cell systems is very limited. Studies reported so far indicated that paradigms based on studies using Arabidopsis are not universally applicable.
The goal of the research unit FOR5235 is to explore whether the complex meristems of cereals are sculpted by conserved but strongly modified, or also by novel signaling pathways and associated gene regulatory networks. The focus lies on maize as an example for a tropical cereal crop (Panicoideae), barley as an example for a temperate cereal crop (Pooideae) and its close relative, the model grass Brachypodium,
Meristems generate vegetative and reproductive plant organs and their activity is regulated and organized by stem cell niches.