２０１７年１１月２４日 Dr. Azam Gholami & Dr. Isabella Guido

日時：２０１７年１１月２４日（金）　１４：４０〜１６：１０
場所：首都大学東京　１１号館３０２号室

講師：Dr. Azam Gholami (MPI for Dynamics and Self-Organization, Germany)
題目：Control of pattern formation in Dictyostelium discoideum
要旨：A classic example of self-generated patterns in nature is found in the social amobae Dictyostelium discoideum. When starved, millions of individual cells signal each other with the signaling molecule cyclic adenosine monophosphate (cAMP). cAMP waves in the form of spiral or target patterns propagate in cell populations and direct aggregation of individual cells to form centimeter-scale Voronoi domains and eventually multicellular fruiting bodies. In this study, we control the shape of Voronoi domains by introducing periodic geometrical obstacles with different size and periodicity in the system. We observe that the obstacles act as aggregation centers and the periodic arrangement of the obstacles is reflected directly in the corresponding Voronoi domains.

講師：Dr. Isabella Guido (MPI for Dynamics and Self-Organization, Germany)
題目：Mechanisms for electric sensing in eukaryotic cells
要旨：Cells have the ability to detect electric fields and respond to them with directed migratory movement. Investigations identified genes and proteins that play important roles in defining the migration efficacy. Nevertheless the sensing mechanisms underlying directed cell migration are still under discussion. We use Dictyostelium discoideum as a model system for studying eukaryotic cell migration in DC electric fields. By analysing the effect of electric fields on vegetative and briefly starved cells we found evidence that conditioned medium factor (CMF), a protein secreted by the cells, when they begin to starve, is an essential factor for triggering the electric sensing of the cells. We found this phenomenon to be independent from the cAMP signalling machinery. When studying fully migratory and cAMP-signalling competent cells we found that, in addition to imposing a directional bias, the electric field influences the cellular kinematics by accelerating the movement of cells along their paths.