Our work is done by an interdisciplinary and collaborative team of curious biologists, mathematicians, engineers and biophysicists. We use multinucleate cells to understand how dynamic compartments can form in the cytoplasm and how cells know their own geometry. Although we are driven to discover the fundamental properties of cells, the work is relevant to the health of humans and the planet.
1.How is cytoplasm spatially organized?
What is the function of biological phase transitions?
How cytosol is spatially organized is not well understood. Using the ability of nuclei to act independently despite sharing a common cytoplasm, we found that mRNAs and disordered proteins come together and condense to form liquid droplets. These droplets position mRNAs near nuclei and sites of growth and we hypothesize regulate translation to create functionally distinct territories of cytosol. Current work in this area is focused on understanding how mRNA sequences encode the material properties of droplets, how cells control where droplets form, how the size of droplets is regulated and what advantage it is to be a liquid for the function of the compartment.
2. How do cells sense their shape?
How do cells control the location, scale and shape of cytoskeletal assemblies on membranes?
Although it is well understood how cells change shape, little is known about how cells may sense their shape and use information about their geometry to localize signaling or make decisions. We have found that the septin cytoskeleton can assemble in a curvature dependent manner. Septins are highly conserved cytoskeletal elements that organize membranes, act as scaffolds and connect to other cytoskeletal networks. By polymerizing into filaments on the scale of microns, septins allow cells to perceive shape changes that are much larger than the size of individual proteins. We are trying to understand how septins sense different curvatures, how different cells may tune the curvature preference for septins and how downstream signaling proteins are recruited to different types of septin assemblies. We are also focused on studying how cells determine the location, the shape and size of septin higher-order structures.
3. What are fungi doing in the marine environment?