Processing bodies (P-bodies) are cytoplasmatic mRNP granules containing 
non-translating mRNAs and proteins from the mRNA decay and silencing 
machineries. The mechanism of P-body assembly has been typically addressed by 
depleting P-body components. Here we apply a complementary approach and 
establish an automated cell-based assay platform to screen for molecules 
affecting P-body assembly. From a unique library of compounds derived from 
myxobacteria, 30 specifically inhibited P-body assembly. Gephyronic acid A (GA), 
a eukaryotic protein synthesis inhibitor, showed the strongest effect. GA also 
inhibited, under stress conditions, phosphorylation of eIF2α and stress granule 
formation. Other hits uncovered interesting novel links between P-body assembly, 
lipid metabolism, and internal organelle physiology. The obtained results 
provide a chemical toolbox to manipulate P-body assembly and function.