c-di-GMP induction of Dictyostelium cell death requires the polyketide DIF-1.
Bottom Line: In these cases, c-di-GMP-induced cell death was rescued by complementation with exogenous DIF-1.Taken together, these results demonstrated that c-di-GMP could trigger cell death in Dictyostelium only in the presence of the DIF-1 polyketide or its metabolites.This identified another element of control to this cell death and perhaps also to c-di-GMP effects in other situations and organisms.
Affiliation: Centre d'Immunologie de Marseille-Luminy, UM2 Aix-Marseille Université; Institut National de la Santé et de la Recherche Médicale, U1104; and Centre National de la Recherche Scientifique, UMR7280, 13288 Marseille, France.Show MeSH
Mentions: In contrast to DH1 cells, Dictyostelium HMX44A cells could be induced to die by DIF-1 but not by c-di-GMP. In separate experiments, DH1- or HMX44A-starved cells were subjected to either 100 nM DIF-1 or 10 μM c-di-GMP (A) for 40 h and then photographed (see Figure 1A legend for details) or (B) for 24 h and then subjected to HL5 medium to allow regrowth of surviving cells; regrown cells were counted after 3 more days (see Figure 1B legend for details). (C) HMX44A cells were subjected in LabTek chambers to graded concentrations of DIF-1 and c-di-GMP in a checkerboard manner. The numbers are the percentages of clumps each comprising at least three vacuolized cells after 17 h in the presence or absence of inducers, established as in the legend to Figure 1A. HMX44A cells showed vacuolization when subjected to DIF-1 alone but not to c-di-GMP alone, and there was synergy between the two inducers. These cells made no endogenous DIF-1, leading to no vacuolization by exogenous c-di-GMP. However, addition of exogenous DIF-1 led to vacuolization through the autonomous DIF-1 pathway and through cooperation with exogenous c-di-GMP (see Figure 5 for schematization).
Affiliation: Centre d'Immunologie de Marseille-Luminy, UM2 Aix-Marseille Université; Institut National de la Santé et de la Recherche Médicale, U1104; and Centre National de la Recherche Scientifique, UMR7280, 13288 Marseille, France.