Spatiotemporal control of ERK pulse frequency coordinates fate decisions during mammary acinar morphogenesis.
                            
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                                CRY2/CIB1
                            
                                CRY2/CRY2
                            
                            
                                
                                    MCF10A
                                
                            
                            
                                Signaling cascade control
                            
                                Control of cytoskeleton / cell motility / cell shape
                            
                                Cell death
                            
                                Developmental processes
                            
                            
                            
                            
                            
                        
                        
                        
                        
                            Abstract:
                            The signaling events controlling proliferation, survival, and apoptosis during mammary epithelial acinar morphogenesis remain poorly characterized. By imaging single-cell ERK activity dynamics in MCF10A acini, we find that these fates depend on the average frequency of non-periodic ERK pulses. High pulse frequency is observed during initial acinus growth, correlating with rapid cell motility and proliferation. Subsequent decrease in motility correlates with lower ERK pulse frequency and quiescence. Later, during lumen formation, coordinated multicellular ERK waves emerge, correlating with high and low ERK pulse frequencies in outer surviving and inner dying cells, respectively. Optogenetic entrainment of ERK pulses causally connects high ERK pulse frequency with inner cell survival. Acini harboring the PIK3CA H1047R mutation display increased ERK pulse frequency and inner cell survival. Thus, fate decisions during acinar morphogenesis are coordinated by different spatiotemporal modalities of ERK pulse frequency.