Cyclic AMP, pattern formation and movement in the slime mould, Dictyostelium discoideum

Abstract

It is important to determine whether a gradient of cyclic AMP exists along the migrating slime mould grex because such a gradient might be involved in pattern formation and the polarity of grex movement. Biochemical measurements provided results which could be consistent with Bonner's suggestion that 50% of the cyclic-AMP produced by the grex is produced by the anterior one-tenth. However, chemotactically sensitive cells cannot detect a gradient of cyclic-AMP emission along the grex. Migrating grex cells themselves are not chemotactically sensitive to cyclic-AMP. It seems unlikely that chemotaxis is involved in controlling the polarity of grex movement.