Rapid Whole Cell Imaging Reveals A Calcium-APPL1-Dynein Nexus That Regulates Cohort Trafficking of Stimulated EGF Receptor

摘要: Multi-cellular life processes such as proliferation and differentiation depend on cell surface signalling receptors that bind ligands generally referred to growth factors. Recently, it has emerged the endosomal system provides rich signal processing capabilities for responses elicited by these At single level, trafficking becomes a critical component of processing, exemplified epidermal factor (EGF) receptor tyrosine kinase family. EGFRs, once activated EGF, are robustly trafficked phosphatase-enriched peri-nuclear region (PNR), where they dephosphorylated. However, details mechanisms regulating movements stimulated EGFR in time space, i.e., towards PNR, not known. How is accumulation at PNR governed? Do modifications upon stimulation regulate its trafficking? To understand events leading translocation, especially early dynamics immediately follow internalization, requires real-time, long-term, whole-cell imaging multiple elements. Here, exploiting advantages lattice light-sheet microscopy, we show binding EGF receptor, EGFR, triggers transient calcium increase peaks 30 s, causing desorption APPL1 from pre-existing endosomes within one minute, rebinding liberated three minutes, dynein-dependent translocation APPL1-EGF-bearing five minutes. The novel, spanning, fast acting network reveal integrates cascade dedicated cohort movement receptors. Our findings support intriguing proposal certain pathways have shed some stochastic strategies traditional trafficking, evolved behaviors whose predictability better suited signaling. Work presented here demonstrates our whole approach can be powerful tool revealing interactions key cellular trafficking.