Joyce Repa, Ph.D.

Dr. Repa’s research at UT Southwestern focuses on the effects of diet and drugs on nuclear receptor regulation of gene expression, and how these signaling pathways contribute to such diseases as atherosclerosis and Type II diabetes. Her research is aimed at understanding the molecular mechanisms by which nuclear orphan receptors regulate lipid and carbohydrate metabolism in the liver, intestine and pancreatic beta cell. The results of this research may provide clues to novel therapies for the treatment of these two very serious diseases.

Undergraduate	University of Wisconsin-madison (1979), Biochemistry
Graduate School	University of Wisconsin-madison (1990), Science
Graduate School	University of Wisconsin-madison (1996), Science

• Bile acids, Cholesterol
• Diabetes
• LXR, FXR, PXR, beta-cell, islet
• Nuclear hormone receptor
• Transcription

Featured Publications

Research resource: nuclear hormone receptor expression in the endocrine pancreas.

Chuang JC, Cha JY, Garmey JC, Mirmira RG, Repa JJ Mol Endocrinol October 2008 22(10) 2353-63

Liver X receptor activation enhances cholesterol loss from the brain, decreases neuroinflammation, and increases survival of the NPC1 mouse.

Repa, J. J., H. Li, T. C. Frank-Cannon, M. A. Valasek, S. D. Turldy, M. G. Tansey, and J. M. Dietschy J. Neurosci. December 2007 27 14470-14480

LXRs control lipid-inducible expression of the apolipoprotein E gene in macrophages and adipocytes.

Laffitte BA, Repa JJ, Joseph SB, Wilpitz DC, Kast HR, Mangelsdorf DJ, Tontonoz P Proc Natl Acad Sci U S A January 2001 98(2) 507-12

Disruption of the sterol 27-hydroxylase gene in mice results in hepatomegaly and hypertriglyceridemia. Reversal by cholic acid feeding.

Repa JJ, Lund EG, Horton JD, Leitersdorf E, Russell DW, Dietschy JM, Turley SD J Biol Chem December 2000 275(50) 39685-92.

Regulation of mouse sterol regulatory element-binding protein-1c gene (SREBP-1c) by oxysterol receptors, LXRalpha and LXRbeta.

Repa JJ, Liang G, Ou J, Bashmakov Y, Lobaccaro JM, Shimomura I, Shan B, Brown MS, Goldstein JL, Mangelsdorf DJ Genes Dev November 2000 14(22) 2819-30

Regulation of absorption and ABC1-mediated efflux of cholesterol by RXR heterodimers.

Repa JJ, Turley SD, Lobaccaro JA, Medina J, Li L, Lustig K, Shan B, Heyman RA, Dietschy JM, Mangelsdorf DJ Science September 2000 289(5484) 1524-9

Inhibiting intestinal NPC1L1 activity prevents diet-induced increase in biliary cholesterol in Golden Syrian hamsters.

Valasek MA, Repa JJ, Quan G, Dietschy JM, Turley SD Am J Physiol Gastrointest Liver Physiol October 2008 295(4) G813-22

Regulation of nuclear import/export of carbohydrate response element-binding protein (ChREBP): interaction of an alpha-helix of ChREBP with the 14-3-3 proteins and regulation by phosphorylation.

Sakiyama H, Wynn RM, Lee WR, Fukasawa M, Mizuguchi H, Gardner KH, Repa JJ, Uyeda K J Biol Chem September 2008 283(36) 24899-908

GM2/GD2 and GM3 gangliosides have no effect on cellular cholesterol pools or turnover in normal or NPC1 mice.

Li H, Turley SD, Liu B, Repa JJ, Dietschy JM J Lipid Res August 2008 49(8) 1816-28

Regulation of lipoprotein lipase by the oxysterol receptors, LXRalpha and LXRbeta.

Zhang Y, Repa JJ, Gauthier K, Mangelsdorf DJ J Biol Chem November 2001 276(46) 43018-24

• Everson Award for distinguished alumni
  presented by the Department of Biochemistry, University of Wisconsin-Madison (2002)