title: Optically triggering spatiotemporally confined GPCR activity in a cell and programming neurite initiation and extension.
abstract: G-protein-coupled receptor (GPCR) activity gradients evoke important cell behavior but there is a dearth of methods to induce such asymmetric signaling in a cell. Here we achieved reversible, rapidly switchable patterns of spatiotemporally restricted GPCR activity in a single cell. We recruited properties of nonrhodopsin opsins--rapid deactivation, distinct spectral tuning, and resistance to bleaching--to activate native Gi, Gq, or Gs signaling in selected regions of a cell. Optical inputs were designed to spatiotemporally control levels of second messengers, IP3, phosphatidylinositol (3,4,5)-triphosphate, and cAMP in a cell. Spectrally selective imaging was accomplished to simultaneously monitor optically evoked molecular and cellular response dynamics. We show that localized optical activation of an opsin-based trigger can induce neurite initiation, phosphatidylinositol (3,4,5)-triphosphate increase, and actin remodeling. Serial optical inputs to neurite tips can refashion early neuron differentiation. Methods here can be widely applied to program GPCR-mediated cell behaviors.
authors.affiliation: Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO 63110, USA.
authors.forename: W K Ajith
authors.initials: WK
authors.lastname: Karunarathne
authors.forename: Lopamudra
authors.initials: L
authors.lastname: Giri
authors.forename: Vani
authors.initials: V
authors.lastname: Kalyanaraman
authors.forename: N
authors.initials: N
authors.lastname: Gautam
mesh_terms: D000242:Cyclic AMP / Q000378:metabolism; D031541:Fluorescence Resonance Energy Transfer; D006801:Humans; D008027:Light; D016501:Neurites / Q000378:metabolism*; D055355:Opsins / Q000378:metabolism / Q000528:radiation effects*; D018129:Phosphatidylinositol Phosphates / Q000378:metabolism; D043562:Receptors, G-Protein-Coupled / Q000378:metabolism*; D015398:Signal Transduction / Q000528:radiation effects*; D059008:Time-Lapse Imaging
chemical_list: D055355:Opsins; D018129:Phosphatidylinositol Phosphates; D043562:Receptors, G-Protein-Coupled; C060974:phosphatidylinositol 3,4,5-triphosphate; D000242:Cyclic AMP