Curvotaxis and pattern formation in the actin cortex of motile cells

Amoeboid cell migration is a crucial part of life. Neutrophil granulocytes, a kind of phagocytes of the mammalian immune system, migrate from blood vessels through tissue towards spots of inflammation. To find this inflammation, they use a chemical “compass” that contains a system to receive and process a chemical signal that guides the neutrophil to the inflammation by leading it towards higher concentration of a chemoattractant molecule. This process is known as chemotaxis, plays also major role is cancer metastasis. The social amoeba Dictyostelium discoideum (D.d.) is a commonly used model organism to study migration as well as chemotaxis. In this study the cell migration of D.d. was investigated within the concept of chemotaxis as well as regarding the geometrical environment of the cells. Here it was found that cells prefere to migrate along paths of high curvature. Hence this finding was called “Curvotaxis”. The open question of a temporal shift between the signalling molecule Ras-G the actin polymerization and the forming of pseudopods was solved by the finding the Ras-G was visible before actin and the propulsion