The macrophage is the primary differentiated cell of the mononuclear phagocyte system and plays a major role in host defense against microbial infections. Phagocytes possess a diversity of plasma membrane receptors which recognize and bind both particulate and soluble stimuli found in body fluids. The activated macrophage secretes a large array of small and macromolecular products including, cytokines, chemokines, growth factors, and oxidative metabolites. While it is well known that receptor-ligand binding is the initial step in the intracellular signal transduction cascades that eventuate secretion and/or phagocytosis, the calcium and G protein dependence of the pathway(s) which links receptor binding and cross-linking to vesicle fusion is still unclear. Studies in this application are directed at the development of a model for secretion in phagocytic cells following stimulation with both soluble and particulate stimuli. The regulation of the secretory process, the proteins involved, and the identity of the vesicles themselves remain poorly understood. We will examine the regulation of the secretory process by independent manipulation of internal calcium concentration and GTP-gamma-S. Preliminary studies strongly support a model in which Ca and G proteins act independently of one another in the regulation of granulocyte secretion. It is our goal in this application to determine the complementary roles of G proteins and cytosolic calcium in the modulation of secretion induced by Fe-receptor cross linking. We will use a combination of single cell capacitance measurements coupled with amperometry and fluorimetry to determine the contribution of the two pathways and determine a possible mechanism of action. It is our hypothesis that cytosolic Ca helps mobilize vesicles from a reserve pool and promotes docking at the plasma membrane while G proteins trigger the actual fusion step. In the development of a comprehensive model, we will (1) examine the complementary roles of cytosolic Ca and G proteins in the mobilization and docking steps of the secretory process, (2) investigate the identity of the Ca receptor in the secretory response, and (3) identify the G proteins involved in the vesicle fusion process.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM036823-17
Application #
7087015
Study Section
Cell Development and Function Integrated Review Group (CDF)
Program Officer
Shapiro, Bert I
Project Start
1986-07-01
Project End
2007-06-30
Budget Start
2006-07-01
Budget End
2007-06-30
Support Year
17
Fiscal Year
2006
Total Cost
$268,049
Indirect Cost
Name
University of Chicago
Department
Biology
Type
Schools of Medicine
DUNS #
005421136
City
Chicago
State
IL
Country
United States
Zip Code
60637
Meijer, Laurent; Nelson, Deborah J; Riazanski, Vladimir et al. (2016) Modulating Innate and Adaptive Immunity by (R)-Roscovitine: Potential Therapeutic Opportunity in Cystic Fibrosis. J Innate Immun 8:330-49
Riazanski, Vladimir; Gabdoulkhakova, Aida G; Boynton, Lin S et al. (2015) TRPC6 channel translocation into phagosomal membrane augments phagosomal function. Proc Natl Acad Sci U S A 112:E6486-95
Domingue, Jada C; Ao, Mei; Sarathy, Jayashree et al. (2014) HEK-293 cells expressing the cystic fibrosis transmembrane conductance regulator (CFTR): a model for studying regulation of Cl- transport. Physiol Rep 2:
Farmer, Laurel M; Le, Brandy N; Nelson, Deborah J (2013) CLC-3 chloride channels moderate long-term potentiation at Schaffer collateral-CA1 synapses. J Physiol 591:1001-15
Riazanski, Vladimir; Deriy, Ludmila V; Shevchenko, Pavel D et al. (2011) Presynaptic CLC-3 determines quantal size of inhibitory transmission in the hippocampus. Nat Neurosci 14:487-94
Deriy, Ludmila V; Gomez, Erwin A; Jacobson, David A et al. (2009) The granular chloride channel ClC-3 is permissive for insulin secretion. Cell Metab 10:316-23
Deriy, Ludmila V; Gomez, Erwin A; Zhang, Guangping et al. (2009) Disease-causing mutations in the cystic fibrosis transmembrane conductance regulator determine the functional responses of alveolar macrophages. J Biol Chem 284:35926-38
Mitchell, Jennifer; Wang, Xueqing; Zhang, Guangping et al. (2008) An expanded biological repertoire for Ins(3,4,5,6)P4 through its modulation of ClC-3 function. Curr Biol 18:1600-5
Di, Anke; Brown, Mary E; Deriy, Ludmila V et al. (2006) CFTR regulates phagosome acidification in macrophages and alters bactericidal activity. Nat Cell Biol 8:933-44
Wang, Xue Qing; Deriy, Ludmila V; Foss, Sarah et al. (2006) CLC-3 channels modulate excitatory synaptic transmission in hippocampal neurons. Neuron 52:321-33

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