Developmental Cell Biology
Our group combines cell and developmental biology to investigate the molecular and cellular mechanisms of morphogenesis. The main question we want to answer is: How do complex shapes and patterns emerge from the interactions of individual cells? To answer this, we follow two approaches:
- We want to decompose complex morphogenetic processes into their cellular and molecular mechanisms.
- We want to understand the differential regulation of conserved cellular mechanisms in the context of a developing organism.
Our model for a complex morphogenetic process is head formation in the roundworm Caenorhabditis elegans. This process relies on a cooperation between sensory organ, nervous system, foregut, mouth, and muscle morphogenesis to assemble a coherent organs system. We have successfully developed an integrated platform that allows us to analyse head formation quantitatively at single-cell resolution. This platform consists of high-resolution time-lapse microscopy, automated cell tracking, and lineage tracing. We combine this with genetics, optogenetics and micromanipulations to decompose newly identified morphogenetic processes into their underlying molecular and cellular mechanisms. Our long-term goal is to describe intertwined organogenesis quantitatively as a dynamically evolving network that unites genetic regulation and cellular interactions.
The Role of Cytokinesis for Development and Differentiation
We study the differential regulation of cytokinesis as a model for a conserved cellular process under developmental control using the C. elegans embryo and mammalian cell culture models: Morphogenesis and differentiation are accompanied by dramatic shape changes of cells. However, one of the most extreme cell shape changes occurs during each cell division. In the context of a tissue, each cell division causes a distortion of the local cellular pattern, which can either be resolved by dynamic restoration or can result in morphogenesis and differentiation. While it has become clear that the differential regulation of mitotic processes plays a crucial role here, evidence is accumulating that the differential regulation of cytokinesis is equally important: We could recently demonstrate that left-right symmetry breaking in C. elegans is timed by cytokinesis, which acts as a developmental clock and as an unexpected signaling mechanism. Our goal is to identify the developmental roles of cytokinesis and the underlying tissue-specific regulation. This will allow us to define different modes of cytokinesis and how they feedback onto morphogenesis and differentiation.
Fig.1| Nervous system morphogenesis in C. elegans