We are interested in understanding how cells are spatially organized. Our efforts concentrate on probing the mechanisms by which cells pattern their periphery to achieve local function. Our work touches on the organization of the cytoskeleton, on the spatial organization of signaling pathways and on principles of cell polarization. We concentrate our efforts on three major aspects
The core cell polarization machinery: We aim to define the composition and mechanisms of the core polarization machinery, addressing how spatial landmarks and feedbacks combine to achieve robust cell polarization. One important factor is the small Rho-family GTPase Cdc42, which drives the organization of the actin cytoskeleton and of secretion at cell poles.
Chemotropism: Most cells are able to respond and orient in response to external chemo-attractants. We use the mating response of yeast cells, during which they polarize growth in response to pheromones, to probe the mechanisms of gradient sensing and cell pairing.
Mechanisms of cell-cell fusion: How do eukaryotic cells fuse together? This is a fundamental process essential for the formation of the zygote during sexual reproduction. We aim to understand how fungal cells locally digest their cell wall and merge their plasma membranes.
Coordination of cell growth with division: Cells reproducibly divide at constant cell size. The mechanisms of cell size homeostasis remain very elusive. We focus on how geometric cues, provided through concentration gradients of a kinase from the cell extremities, contribute to defining an appropriate division size.