title: Calcium oscillations-coupled conversion of actin travelling waves to standing oscillations.
abstract: Dynamic spatial patterns of signaling factors or macromolecular assemblies in the form of oscillations or traveling waves have emerged as important themes in cell physiology. Feedback mechanisms underlying these processes and their modulation by signaling events and reciprocal cross-talks remain poorly understood. Here we show that antigen stimulation of mast cells triggers cyclic changes in the concentration of actin regulatory proteins and actin in the cell cortex that can be manifested in either spatial pattern. Recruitment of FBP17 and active Cdc42 at the plasma membrane, leading to actin polymerization, are involved in both events, whereas calcium oscillations, which correlate with global fluctuations of plasma membrane PI(4,5)P(2), are tightly linked to standing oscillations and counteract wave propagation. These findings demonstrate the occurrence of a calcium-independent oscillator that controls the collective dynamics of factors linking the actin cytoskeleton to the plasma membrane. Coupling between this oscillator and the one underlying global plasma membrane PI(4,5)P2 and calcium oscillations spatially regulates actin dynamics, revealing an unexpected pattern-rendering mechanism underlying plastic changes occurring in the cortical region of the cell.
authors.affiliation: Howard Hughes Medical Institute, Department of Cell Biology and Program in Cellular Neuroscience, Neurodegeneration and Repair, Yale University School of Medicine, New Haven, CT 06520, USA.
authors.forename: Min
authors.initials: M
authors.lastname: Wu
authors.forename: Xudong
authors.initials: X
authors.lastname: Wu
authors.forename: Pietro
authors.initials: P
authors.lastname: De Camilli
mesh_terms: D008841:Actin Cytoskeleton / Q000378:metabolism; D000199:Actins / Q000378:metabolism*; D000818:Animals; D000941:Antigens / Q000008:administration & dosage; D020013:Calcium Signaling / Q000502:physiology*; D002352:Carrier Proteins / Q000378:metabolism; D045744:Cell Line, Tumor; D025461:Feedback, Physiological; D008407:Mast Cells / Q000276:immunology / Q000378:metabolism; D008856:Microscopy, Fluorescence; D018715:Microscopy, Video; D018129:Phosphatidylinositol Phosphates / Q000378:metabolism; D051381:Rats; D020764:cdc42 GTP-Binding Protein / Q000378:metabolism
chemical_list: D000199:Actins; D000941:Antigens; D002352:Carrier Proteins; D018129:Phosphatidylinositol Phosphates; D020764:cdc42 GTP-Binding Protein