Dr. Song’s research is focused on the study of G-protein coupled receptor (GPCR) signaling. G protein coupled receptors, a family of membrane signaling proteins, are the targets of half of the drugs on the market today. Her past research shows that some GPCRs function as dimer or oligomers, and that specific binding molecules regulate receptor signaling and trafficking. Dr. Song is currently focusing primarily on two projects: the study of parathyroid hormone (PTH) receptor signaling in vascular cells and the study of the glucagon-like peptide 1 receptor signaling in the pancreatic islets.

Development of therapeutic drug for vascular diseases

During the past few years, Dr. Song has concentrated on determining the molecular mechanism underlying vascular disease, with particular emphasis on the role of PTHrP and the PTH receptor signaling in the development of arterial restenosis. Her research has revealed some of the mechanisms regulating expression and signal transduction of the PTH1R in vascular smooth muscle cells. Indeed, these molecules are endogenously expressed in vascular smooth muscle cells and play a key role in mediating proliferation and migration of vascular smooth muscle cells, events that are critical for the development of restenosis (the process of occlusion of an artery) following angioplasty. Dr. Song is also interested in the function of EBP50 (Ezin binding protein, NHERF1) a scaffolding protein in the vasculature. She showed that EBP50 contributes to cell-specific signaling by the PTH receptor and contributes to vascular smooth muscle cell proliferation and migration. These observations suggest that targeting EBP50 represents a completely novel potential approach for treating this important complication of a commonly used surgical procedure.

GLP1 receptor regulating insulin secretion and ß cell proliferation

Dr. Song is also involved in the study on glucagon-like peptide 1 receptor (one of the GPCRs) function in pancreatic islets. In particular, the role of the adaptor protein Caveolin-1 in the regulation of receptor expression and function is under investigation. Furthermore, her research aims to determine the role of Caveolin-1 in determining the efficacy of GLP-1R agonists in stimulating insulin secretion and ß cell proliferation in vivo.

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Important Publications

Song GJ, S Barrick, KL Leslie, B Sicari, NM Fiaschi-Taesch and A Bisello.  EBP50 inhibits the anti-mitogenic action of the parathyroid hormone type 1 receptor in vascular smooth muscle cells.  J Mol Cell Cardio 49:1012-1021, 2010.

Song GJ, S Barrick, KL Leslie, B Sicari, NM Fiaschi-Taesch and A Bisello.  EBP50 inhibits the anti-mitogenic action of the parathyroid hormone type 1 receptor in vascular smooth muscle cells.  J Mol Cell Cardio 49:1012-1021, 2010.

Song GJ, N Fiaschi-Taesch and A Bisello.  Endogenous parathyroid hormone-related protein regulates the expression of PTH type 1 receptor and proliferation of vascular smooth muscle cells.  Mol Endocrinol 23:1681-1690, 2009.

Song GJ and V Lewis.  Mitochondrial DNA integrity and copy number in sperm from infertile men.  Fertil Steril 90:2238-2244, 2008.

Song GJ, BW Jones and PM Hinkle.  Dimerization of the thyrotropin-releasing hormone receptor potentiates hormone-dependent receptor phosphorylation.  Proc Natl Acad Sci USA 104:18303-18308, 2007.

Jones BW, GJ Song, EK Greuber and PM Hinkle.  Phosphorylation of the endogenous thyrotropin-releasing hormone receptor in pituitary GH3 cells and pituitary tissue revealed by phosphosite-specific antibodies.  J Biol Chem 282:12893-12906, 2007.

Song GJ, EP Norkus and V Lewis.  Relationship between seminal ascorbic acid and sperm DNA integrity in infertile men.  Int J Androl 29:569-575, 2006.

Song GJ and PM Hinkle.  Regulated dimerization of the thyrotropin-releasing hormone receptor affects receptor trafficking but not signaling.  Mol Endocrinol 19:2859-2870, 2005.

Lee KH, GJ Song, IS Kang, SW Kim, JS Paick, CH Chung and K Rhee.  Ubiquitin-specific protease activity of USP9Y, a male infertility gene on the Y chromosome.  Reprod Fertil Dev 15:129-133, 2003.