|Title||The onset of collective behavior in social amoebae.|
|Publication Type||Journal Article|
|Year of Publication||2010|
|Authors||Gregor, T, Fujimoto, K, Masaki, N, Sawai, S|
|Date Published||2010 May 21|
|Keywords||3',5'-Cyclic-AMP Phosphodiesterases, Adenylate Cyclase, Cell Aggregation, Cell Count, Cyclic AMP, Cyclic AMP-Dependent Protein Kinases, Cytosol, Dictyostelium, Fluorescence Resonance Energy Transfer, Models, Biological, Periodicity, Protozoan Proteins, Quorum Sensing, Signal Transduction, Stochastic Processes|
In the social amoebae Dictyostelium discoideum, periodic synthesis and release of extracellular cyclic adenosine 3',5'-monophosphate (cAMP) guide cell aggregation and commitment to form fruiting bodies. It is unclear whether these oscillations are an intrinsic property of individual cells or if they exist only as a population-level phenomenon. Here, we showed by live-cell imaging of intact cell populations that pulses originate from a discrete location despite constant exchange of cells to and from the region. In a perfusion chamber, both isolated single cells and cell populations switched from quiescence to rhythmic activity depending on the concentration of extracellular cAMP. A quantitative analysis showed that stochastic pulsing of individual cells below the threshold concentration of extracellular cAMP plays a critical role in the onset of collective behavior.