Richard W. Gross
Campus Box 8020
St. Louis, MO 63110
Our research is focused on the chemical biology of membranes in health and disease. Biologic membranes are comprised of a structurally diverse array of thousands of distinct chemical entities in a bilayer configuration that are in constant motion providing a rich repertoire of chemical forces that can be used to modulate the conformation and function of transmembrane proteins such as ion channels and ion pumps. Through adaptation of a bilayer structure membranes serve as a hydrophobic scaffold for the organization of complex supramolecular chemical assemblies that are used in biologic systems as signaling platforms.
These highly specialized signaling assemblies facilitate the transmission of chemical information between intracellular membrane compartments as well as the intercellular flow of information between cells. Biologic membranes also serve as the intracellular storage depot of latent lipid second messengers of signal transduction (e.g., esterified arachidonic acid) that are hydrolyzed by phospholipases in response to changes in a cell’s external environment or after receipt of a chemical or electrical signal from distant cells. Finally, biologic membrane bilayers are the fundamental structural elements responsible for the trafficking of proteins, lipids and nucleic acids to different compartments within cells or, through membrane fusion, for the release of information from a genetically programmed specialized cell into the blood stream (e.g., insulin release into the blood stream from b cells in the pancreas). Our laboratory uses and develops many different chemical methods to study the structure and function of membrane systems to both advance our understanding of the fundamental processes underlying the chemistry of biologic membranes and to use this information to develop new strategies to have a favorable impact on the major disease processes of the 21st century.
Recently, industrialized nations have been afflicted with an epidemic of obesity precipitating the metabolic syndrome (hypertension, diabetes and atherosclerosis). To identify the chemical mechanisms through which obesity predisposes to these disease processes, we have developed a novel technology, termed shotgun lipidomics, which allows the direct identification and quantitation of hundreds of lipid molecular species directly from organic extracts of tissue or biologic fluids.
Shotgun lipidomics is comprised of intrasource separation, multidimensional mass spectrometry, and array analysis. Through the judicious use of stable isotopes, alterations in the kinetics of specific membrane chemical processes, and the dynamics of lipid-protein and lipid-lipid interactions can be readily examined with unprecedented speed and accuracy. Currently we are using this technology to explore altered heart metabolism (metabolomics) through a systematic chemical biology approach. Through the identification of critical metabolic nodes specific to disease states and the effects of pharmaceuticals on the influx and efflux of metabolites into common intermediates, new insights into dysfunctional lipid metabolism in disease and the effects of therapeutic agents can be gathered.
During the last decade, we have made substantial progress in understanding the chemical mechanisms regulating the intracellular phospholipases that release lipid second messengers. Through recombinant DNA techniques, we now express large quantities of these proteins to study their structure and regulatory mechanisms through a variety of chemical and molecular biologic methods. Of particular current interest are the mechanisms that regulate the recognition of membrane surfaces by signaling phospholipases and the resultant alterations in protein structure and function they engender.The recent identification of new signaling mechanisms mediated through phospholipase-calmodulin membrane-associated signaling platforms is rapidly expanding our understanding of the partnership of membranes and proteins in signaling functions. Through exploiting new advances in proteomics using both electrospray ionization (ESI) and matrix assisted laser desorption/ionization (MALDI) quadrupole time of flight spectrometer, high throughput analyses of the specific chemical mechanisms, and protein-target interactions regulating signaling phospholipases in multiple biologically relevant context can be made. Through this work, we seek to understand the mechanisms activating signaling proteins and identify new targets for pharmaceutical intervention.
1992-present, Division Chief, Department of Bioorganic Chemistry and Molecular Pharmacology, Washington University
1991-present, Professor of Medicine, Department of Internal Medicine, Washington University
1991-present, Professor, Department of Chemistry, Washington University
1991-present, Professor, Department of Developmental Biology, Washington University
Yan, W., Jenkins, C.M., Han, X., Mancuso, D.J., Sims, H.F., Yang, K., and Gross, R.W. The highly selective production of 2-arachidonoyl lysophosphatidylcholine catalyzed by purified calcium-independent phospholipase A2g (iPLA2g): Identification of a novel enzymatic mediator for the generation of a key branch point intermediate in eicosanoid signaling. J. Biol. Chem. 2005, 280:26669-26679. PMID:15908428.
Han, X., Yang, J., Cheng, H., Yang, K., Abendschein, D.R., and Gross, R.W. Shotgun lipidomics identifies cardiolipin depletion in diabetic myocardium linking altered substrate utilization with mitochondrial dysfunction. Biochemistry 2005, 44:16684-16694. PMID:16342958.
Jenkins, C.M., Yan, W., Mancuso, D.J. and Gross, R.W. Highly selective hydrolysis of fatty acyl-CoAs by calcium-independent phospholipase A2b: Enzyme autoacylation and acyl-CoA-mediated reversal of calmodulin inhibition of phospholipase A2 activity. J. Biol. Chem. 2006, 281:15615-15624. PMID:16595686.
Mancuso, D.J., Han, X., Jenkins, C.M., Lehman, John J., Sambandam, N., Sims, H.F., Yang, J., Yan, W., Yang, K., Green, K., Abendschein, D.R., Saffitz, J.E., and Gross, R.W. Dramatic Accumulation of triglycerides and precipitation of cardiac hemodynamic dysfunction during brief caloric restriction in transgenic myocardium expressing human calcium-independent phospholipase A2g J. Biol. Chem. 2007, 282:9216-9227. PMID:17213206.
Han, X, Yang, J, Yang, K, Zhao, Z, Abendschein, DR, and Gross, RW. Alterations in myocardial cardiolipin content and composition occur at the very earliest stages of diabetes: A shotgun lipidomics study. Biochemistry 2007, 46:6417-6428. PMID:2139909.
Sun, G, Yang, K, Zhao, Z, Guan, S, Han, X, and Gross, RW. Shotgun metabolomics approach for the analysis of negatively charged water-soluble cellular metabolites from mouse heart tissue. Anal. Chem. 2007, 79:6629-6640. PMID:17665876
Mancuso, DJ, Sims, HF, Han, X, Jenkins, CM, Guan, SP, Yang, K, Moon, SH, Pietka, T, Abumrad, N, Schlesigner, PH, and Gross, RW. Genetic Ablation of Calcium-independent Phospholipase A2g Leads to Alterations in Mitochondrial Lipid Metabolism and Function Resulting in a Deficient Mitochondrial Bioenergetic Phenotype. J. Biol. Chem. 2007, 282:34611-34622. PMID:17923475.
Moon, SH, Jenkins, CM, Mancuso, DJ, Turk, J, and Gross, RW. Smooth muscle cell arachidonic acid release, migration, and proliferation are markedly attenuated in mice null for calcium-independent phospholipase A2b. J. Biol. Chem. 2008, 283:33975-33987. PMID:18927078.
Sun, G, Yang, K, Zhao, Z, Guan, S, Han, X, and Gross, RW. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometric analysis of cellular glycerophospholipids enabled by multiplexed solvent dependent analyte-matrix interactions. Anal. Chem. 2008, 80:7576-7585. PMID:18767869.
Chen, M., Su, X., Yang, J., Jenkins, C.M., Cedars, A.M., and Gross, R.W. Facile identification and quantitation of protein phosphorylation via b-elimination and Michael Addition with natural abundance and stable isotope labeled thiocholine. Anal. Chem. 2010, 82:163-171. PMCID: PMC2813211.
Mancuso, D.J., Sims, H.F., Yang, K., Kiebish, M.A., Su, X., Jenkins, C.M., Guan, S., Moon, S.H., Pietka, T., Nassir, F., Schappe, T., Moore, K., Han, X., Abumrad, N.A., and Gross, R.W. Genetic ablation of calcium-independent phospholipase A2g prevents obesity and insulin resistance during high fat feeding by mitochondrial uncoupling and increased adipocyte fatty acid oxidation. J. Biol. Chem. 2010, 285:36495-36510. PMCID: PMC2978578.
Jenkins, C.M., Yang, J., Sims, H.F., and Gross, R.W. Reversible high affinity inhibition of phosphofructokinase-1 by acyl-CoA: A mechanism integrating glycolytic flux with lipid metabolism. J. Biol. Chem. 2011, 286:11937-11950. PMCID: PMC3069396.
Gross, R.W., and Han, X. Lipidomics at the interface of structure and function in systems biology. Chem. Biol. 2011, 18:284-291. PMCID: PMC3132894.
Moon, S.H., Jenkins, C.M., Liu, X., Guan, S., Mancuso, D.J., and Gross, R.W. Activation of mitochondrial calcium-independent phospholipase A2g (iPLA2g) by divalent cations mediating arachidonate release and the production of downstream eicosanoids. J. Biol. Chem. 2012, 287:14880-14895. PMCID: PMC3340231.
Kiebish, M.A., Yang, K., Sims, H.F., Jenkins, C.M., Liu, X., Mancuso, D.J., Zhao, Z., Guan, S., Abendschein, D.R., Han, X., and Gross, R.W. Mycardial regulation of lipidomic flux by cardiolipin synthase: Setting the beat for bioenergetic efficiency. J. Biol. Chem. [Epub. ahead of print May 14, 2012]. PMCID: “PMC Journal-In Process”.
Moon, S.H., Jenkins, C.M., Kiebish, M.A., Sims, H.F., Mancuso, D.J., and Gross, R.W. Genetic ablation of calcium-independent phospholipases A2g (iPLA2g) attenuates calcium-induced opening of the mitochondrial permeability transition pore and resultant cytochrome C release. J. Biol. Chem. 2012 Jul 9. [Epub ahead of print]. PMCID: “PMC Journal-In Process”.
Attending Physician--Barnes Hospital
Chemistry 476, The Chemistry of Biological Membranes
Lipid Mediators of Signal Transduction