The onset of collective behavior in social amoebae.
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.
Gregor
Thomas
T
Graduate School of Arts and Sciences, University of Tokyo, Tokyo 153-8902, Japan.
Fujimoto
Koichi
K
Masaki
Noritaka
N
Sawai
Satoshi
S
D015105:3',5'-Cyclic-AMP Phosphodiesterases / Q000378:metabolism; D000262:Adenylyl Cyclases / Q000378:metabolism; D002449:Cell Aggregation; D002452:Cell Count; D000242:Cyclic AMP / Q000378:metabolism* / Q000494:pharmacology; D017868:Cyclic AMP-Dependent Protein Kinases / Q000235:genetics / Q000378:metabolism; D003600:Cytosol / Q000378:metabolism; D004023:Dictyostelium / Q000166:cytology / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D031541:Fluorescence Resonance Energy Transfer; D008954:Models, Biological; D010507:Periodicity; D015800:Protozoan Proteins / Q000235:genetics / Q000378:metabolism; D053038:Quorum Sensing; D015398:Signal Transduction; D013269:Stochastic Processes
D015800:Protozoan Proteins; D000242:Cyclic AMP; D017868:Cyclic AMP-Dependent Protein Kinases; D015105:3',5'-Cyclic-AMP Phosphodiesterases; C112742:regA protein, Dictyostelium; D000262:Adenylyl Cyclases