Robert C. Dickson
Professor
B.S. University of Redlands
Ph.D. University of California, Los Angeles
bobd@pop.uky.edu
859-323-6052

Research Interests  |  Publications  |  PubMed

Research Interests:

    Sphingolipids are ubiquitous components of eucaryotic cells. Their specific functions are only beginning to be discovered. Emerging results from mammals suggest that sphingolipids and their breakdown products are components of signal transduction pathways necessary for promoting and halting cell division, for inducing programmed cell death (apoptosis) in response to stress, for regulating angiogenesis and endothelial cell growth and for regulating heart development. Since this is a young field of research there are likely to be many more functions to be uncovered.
    Our current focus is on sphingolipids that act as second messengers to control signal transduction pathways.  We are particularly interested in sphingolipid long chain bases.  These are linear molecules of 18 or 20 carbons with hydroxyls at the 1, 3 or 4 positions and an amino group at the 2 position.  They play roles in regulating signal transduction pathways that control stress resistance, movement of the actin cytoskeleton, endocytosis, remodeling of the extracellular matrix, protein synthesis and responses to nutrient depletion.  Most of these signaling pathways are poorly defined and our goal is to elucidate them at the molecular level beginning with which protein kinases are regulated by long chain bases and terminating with the cellular process that is regulated. 
    Another area of interest in the laboratory is to understand the role of sphingolipids in regulating aging.  We are examining signaling pathways that appear to be regulated by sphingolipid long chain bases and that control the protein kinases Pkh1 and Sch9, both of which play roles in regulating chronological life span, which is a model for the life span of non-dividing cells such as found in the mammalian nervous system.  Our studies focus on identifying substrates of Sch9 and determining their role in life span.

Representative Publications:

Brace, J., L., Lester, R. L., Dickson, R. C. and Rudin, C. M. (2007) SVF1 Regulates Cell Survival by Affecting Sphingolipids Metabolism in Saccharomyces cerevisiae.  Genetics, 175:65-76.

Hearn, J. D., Lester, R. L. and Dickson, R. C. (2003) The uracil transporter Fur4p associates with lipid rafts. J. Biol. Chem. 278:3679-3686.
 
Chung, J-H., Lester, R. L. and Dickson, R. C. (2003) Sphingolipid requirement for functional association of the Vacuolar ATPase domains V₁ and V₀.  J. Biol. Chem. 278:28872-28881.
 
Zhang, X., Lester, R. L. and Dickson, R. C. (2004) Pil1p and Lsp1p negatively regulate the PKD1-like kinase Pkh1p and downstream signaling pathways Pkc1p and Ypk1p. J. Biol. Chem. 279:22030-22038.
 
Liu, K., Zhang, X., Lester, R. L. and Dickson R. C. (2005) The sphingolipid long chain bases phytosphingosine activates AGC kinases in Saccharomyces cerevisiae including Ypk1, Ypk2 and Sch9. J. Biol. Chem. 280:22679-22687.
 
Dickson, R. C., Sumanasekera, C. and Lester, R. L. (2006) Function and Metabolism of Sphingolipids in Saccharomyces cerevisiae.  Progress in Lipid Research, 45:447-465.