Robert Rebres Email and Phone Number

Completed two manuscripts on AfCS projects

Investigations for the Alliance for Cellular Signaling (www.afcs.org) addressed macrophage signal-transduction pathway cross-talk. Our lab examined GPCR signal-interactions and dependencies for Ca2+ responses using genetic (RNAi (LV, RV, si), KO), pharmacologic, and other experimental perturbations to identify specific biochemical mechanisms for synergistic or inhibitory effects.* Examined molecular mechanisms of synergistic GPCR calcium responses in primary and transformed macrophages* Probed C. difficile toxin effects on macrophage signal-transduction pathways* Screened phenotypes in GPCR signaling pathway by lentiviral RNAi of protein targets * Performed assay development for ligand screens* Established single-cell calcium assay platform and analytical methods * Developed custom software for data processing and analysis, database storage and mining of large volume data sets, and automated statistical analyses.

This was the host institute for the Alliance for Cellular Signaling'sMacrophage Biology Lab in San Francisco

Projects on CD47 structure/function in Eric J. Brown's lab* Generated and evaluated CD47 mutants/chimeras in signaling, localization, and functional assays. Assays of calcium flux, signaling protein phosphorylation and/or translocation, G-protein activation, cellular F-actin content cytokine secretion, cell adhesion, and cell migration* Identified CD47 signaling effects in synergy with T cell activation: changes in F-actin cytoskeleton and PKC-theta translocation were linked to membrane raft association, while effects on calcium signaling were independent* Detected a novel intramolecular long-range disulfide bond and investigated its effect on CD47 ligand binding, protein-protein interactions, calcium signaling, cell adhesion and APC-stimulated T cell activation* Identified and characterized a CD47-mediated homophilic adhesion mechanism, characterized the signaling pathways regulating its activity, and examined its influence on lymphocyte migration.

Projects on CD47 structure/function in Eric J. Brown's lab* Developed single-cell calcium assays of CD47 synergy with the TCR and used chimeric forms of CD47 to identify the structural requirements for this phenotype.* Generated several CD47 transmembrane domain mutants and performed functional screens in calcium signaling assays in Jurkat cells.* Reconstituted CD47-deficient fibroblast and epithelial cell lines with CD47 mutants and screened for phenotypes in cell signaling and adhesion assays. Identified CD47-conferred enhancement in cell proliferation in association with differential activation of MAPKs.