Multicellular organisms develop by integrating and coordinating multiple growth programs. In plants, a paradigm for such systems is the secondary growth (thickening) of stems and roots. Secondary growth provides the mechanical support and stability that plants need to expand their longitudinal growth, to generate new growth axes in the form of branches and to sustain new structures such as fruits, leaves or flowers. In addition to playing a crucial role in plant development, secondary growth is of relevant social and economic importance. First, in trees, secondary growth brings about wood: one of the largest sources of terrestrial biomass, the largest sink of atmospheric CO2 after oceans and a main source of raw material for the renewable energy, construction, timber, paper or pulp industries. Second, in terms of agriculture, secondary growth is key for determining crop architecture and properties.
Secondary growth is the result of the formation of secondary vascular tissues (secondary xylem and secondary phloem). The secondary vascular tissues develop through the activity of a highly specialized pool of stem cells (meristem) termed cambium. In our lab we focus mainly in (i) the genetic regulation of cellular proliferation within the cambium and (ii) the impact of cambium-mediated cell fate determination on organ architecture. We use specific plant species depending on the actual question to be addressed. In my talk I will summarize our work in Arabidopsis thaliana (which we use as an example to study cellular proliferation in the cambium) and in Manihot esculenta (Cassava), which we use as an example to understand the impact of cell fate determination on organ architecture. Due to the social relevance of Cassava, potential applications of our work will be discussed.
[mehr]