Neutrophils are innate immune cells that use directed migration to hunt and kill bacteria. This directed migration depends on several fundamental signaling capabilities. Neutrophils can migrate up chemotactic gradients spanning several orders of magnitude, requiring signaling adaptation so that cells respond to relative changes rather than steady-state concentrations of ligand. Neutrophils generate a consistent internal polarity that does not depend on the steepness of the external gradient, requiring positive feedback to amplify subtle signaling asymmetries and long-range inhibition so that protrusions can compete with one another to generate a dominant leading edge. Through genetic and pharmacological loss-of-function experiments, we know many of the core components required for chemotaxis. However, there are still fundamental gaps in our understanding of the how these signaling components interact to generate cell polarity and movement. Because the overall process of polarity is highly complex, we have developed tools to isolate and dissect individual steps in the signaling cascade to better understand the overall signaling circuit. In the last gran period, we developed a general approach for quantitative optogenetic control of intracellular signaling in mammalian cells. This system gives us unprecedented spatial and temporal control of a wide range of intracellular signals and will enable us to dissect the logic of signal processing in a manner that has not been possible with conventional tools. Quantitative control of intracellular signals has played a fundamental role in uncovering the logic of action potentials and bacterial chemotaxis, and we envision that our optogenetic tools will be similarly transformative for understanding cell polarity in neutrophils.
Our specific aims are to understand the sensory adaptation that accounts for the remarkable dynamic range of chemotaxis (Aim 1) and to dissect the positive feedback loops (Aim 2) and long-range inhibition (Aim 3) that make neutrophil polarity possible.
Directed cell migration is essential for a number of biological processes: it allows innate immune cells to seek and destroy pathogens, it is essential for the morphogenesis of animals, and misregulation of cell migration is intimately involved in many diseases. The ability to control cell migration would be a valuable tool for combating atherosclerosis, inflammation, metastasis, and other pathological processes that occur upon the disruption of cellular guidance mechanisms.
|Hoeller, Oliver; Toettcher, Jared E; Cai, Huaqing et al. (2016) GÎ² Regulates Coupling between Actin Oscillators for Cell Polarity and Directional Migration. PLoS Biol 14:e1002381|
|Buckley, Clare E; Moore, Rachel E; Reade, Anna et al. (2016) Reversible Optogenetic Control of Subcellular Protein Localization in a Live Vertebrate Embryo. Dev Cell 36:117-26|
|Diz-MuÃ±oz, Alba; Thurley, Kevin; Chintamen, Sana et al. (2016) Membrane Tension Acts Through PLD2 and mTORC2 to Limit Actin Network Assembly During Neutrophil Migration. PLoS Biol 14:e1002474|
|Genuth, Miriam A; Weiner, Orion D (2015) Cell Migration: Recoiling from an Embrace. Curr Biol 25:R566-8|
|Yu, Dan; Baird, Michelle A; Allen, John R et al. (2015) A naturally monomeric infrared fluorescent protein for protein labeling in vivo. Nat Methods 12:763-5|
|Jost, Anna Payne-Tobin; Weiner, Orion D (2015) Probing Yeast Polarity with Acute, Reversible, Optogenetic Inhibition of Protein Function. ACS Synth Biol 4:1077-85|
|Wu, Julie; Pipathsouk, Anne; Keizer-Gunnink, A et al. (2015) Homer3 regulates the establishment of neutrophil polarity. Mol Biol Cell 26:1629-39|
|Lou, Sunny S; Diz-MuÃ±oz, Alba; Weiner, Orion D et al. (2015) Myosin light chain kinase regulates cell polarization independently of membrane tension or Rho kinase. J Cell Biol 209:275-88|
|Park, Jason S; Rhau, Benjamin; Hermann, Aynur et al. (2014) Synthetic control of mammalian-cell motility by engineering chemotaxis to an orthogonal bioinert chemical signal. Proc Natl Acad Sci U S A 111:5896-901|
|Motta-Mena, Laura B; Reade, Anna; Mallory, Michael J et al. (2014) An optogenetic gene expression system with rapid activation and deactivation kinetics. Nat Chem Biol 10:196-202|
Showing the most recent 10 out of 36 publications