Julien Sebag, PhD

Contact Information

Office: 3330 PBDB
Phone: 319-335-3270
Faculty Profile

Brief description of current research:

Our laboratory focuses on identifying new pathways involved in the control of energy homeostasis and discovering novel targets for the treatment of obesity and diabetes. We recently identified the Melanocortin Receptor Accessory Protein 2 (MRAP2) as critical for the maintenance of proper energy balance. Indeed, the loss of MRAP2 in mice and humans results in severe obesity. Therefore, identifying the mechanisms by which MRAP2 regulates energy expenditure and the signaling pathways involved is a major goal of our laboratory. Using proteomic methods we have identified promising new targets for the treatment of obesity. In addition to studying the basic mechanisms through which those proteins contribute to the control of energy homeostasis, we are attempting to identify small molecule modulators using high throughput screening. Our goal is to select lead compounds that could become useful in the development of novel treatments for obesity and diabetes.

3 most influential diabetes/obesity/metabolism publications:

  • Developmental control of the melanocortin-4 receptor by MRAP2 proteins in zebrafish. 
    Sebag JA, Zhang C, Hinkle PM, Bradshaw AM, Cone RD. 
    Science. 2013 Jul 19;341(6143):278-81. doi: 10.1126/science.1232995. 
    PMID: 23869017
  • Regulation of G protein-coupled receptor signaling: specific dominant-negative effects of melanocortin 2 receptor accessory protein 2. 
    Sebag JA, Hinkle PM. 
    Sci Signal. 2010 Apr 6;3(116):ra28. doi: 10.1126/scisignal.2000593. 
    PMID: 20371771 [PubMed - indexed for MEDLINE] Free PMC Article
  • Melanocortin-2 receptor accessory protein MRAP forms antiparallel homodimers. 
    Sebag JA, Hinkle PM. 
    Proc Natl Acad Sci U S A. 2007 Dec 18;104(51):20244-9. Epub 2007 Dec 12. 
    PMID: 18077336 [PubMed - indexed for MEDLINE] Free PMC Article 


So far the development of drugs to treat obesity has been largely unsuccessful and several of the targets first identified as promising have been abandoned. However, obesity is a devastating disease and we are in desperate need for an efficacious treatment. Our goal is to identify new targets with the hope that they will allow for the development of a safe and effective treatment for obesity.