“…In addition to having differentiation-inducing activities, DIFs 1 and 2 at nanomolar levels function as modulators for Dictyostelium chemotactic cell movement toward cyclic adenosine monophosphate (cAMP) [48,49]. Importantly, the mechanisms for the modulation of chemotaxis by DIFs differ, at least in part, from those for the induction of stalk-cell differentiation [48,49,50]. Since the discovery of DIFs 1 and 2, the mechanisms underlying their functions have been examined [11,41,44,45,46,47,48,49,50,51,52,53,54,55,56,57] but remain to be fully elucidated; most importantly, their receptors have not been determined.…”