Michael J. Garant, Ph.D.
Assistant Professor of Medicine

Ph.D.: University of Massachusetts Lowell Department of Chemistry

Research Interests: My research interests lie in the molecular and cellular mechanisms of insulin signaling. While looking for potential redox sites in the insulin receptor that affect insulin signaling, I was the first to definitively identify a critical thiol in the insulin receptor and a thiol reactive protein that reacts with the insulin receptor and is believed to be involved with insulin signaling. Most recently, these studies have been extended to include epigenetic and molecular genetic studies of obesity and type 2 diabetes in humans and rhesus monkeys. Understanding the underlying genetic and molecular mechanisms that contribute to these complex disorders will potentially lead to new treatments and strategies for preventing these debilitating diseases.

Aberrant DNA methylation increases with age and alters the expression of specific gene products potentially contributing to increased susceptibility to a wide range of age-related diseases. I am interested in the potential role of DNA methylation in glucose homeostasis and type 2 diabetes. By using tissue samples obtained from rhesus monkeys and applying microarray techniques, methylation specific PCR (MSP), as well as enzymatic regional methylation assays (ERMA), I am examining DNA methylation patterns in muscle, fat and liver of multiple genes involved in glucose metabolism. Future studies will focus on human tissues.

I am also interested in the genetics of type 2 diabetes and obesity. These studies have led to the findings that a missense mutation in the beta-1-adrenergic receptor gene is associated with higher body-mass- index in Caucasian women, and that a SNP in the calpain 10 gene is associated with an increased risk for type 2 diabetes in African-Americans. I am currently using denaturing HPLC and DNA sequencing to search for polymorphisms in several other candidate genes for type 2 diabetes and obesity.

Academic Office:410-706-1634
Fax:  410-706-1622
E-mail:  garant@medicine.umaryland.edu

Address:
University of Maryland, School of Medicine
Department of Medicine
Division of Endocrinology, Diabetes and Nutrition
660 W. Redwood Street
Laboratory: Howard Hall, Room 480
Office: Howard Hall, Room 592
Baltimore, Maryland  21201

Key Papers

  1. Kole H, Garant MJ, Kole S & Bernier M, (1996). A peptide based protein tyrosine phosphatase inhibitor specifically enhances insulin receptor function in intact cells. J. Biol. Chem., 271(24): 14302-14307.

  2. Montrose-Rafizadeh C, Avdonin P, Garant MJ, Rodgers BD, Kole S, Yang H, Levine M, Schwindinger W & Bernier M, (1999). Pancreatic GLP-1 couples to multiple G-proteins and activates MAP kinase pathways in Chinese hamster ovary cells. Endocrinology, 140(3): 1132-1140.

  3. Garant MJ, Kole S & Bernier M, (1999). Reversible changes in thiol redox status of the insulin receptor a-subunit in intact cells. Biochemistry, 38(18): 5896-5904.

  4. Garant MJ, Maksimova E, Montrose-Rafizadeh C, Lee-Kwon W, Kole S & Bernier M, (2000). Cysteine-981 of the human insulin receptor is required for covalent cross-linking between b-subunit and thiol-reactive membrane-associated protein. Biochemistry, 39(24): 7178-7187.

  5. Garant MJ, Kao WH, Brancati F, Coresh J, Hanis C, Boerwinkle E & Shuldiner AR, (2002). SNP43 of the Calcium-Activated Neutral Protease (CAPN10) is associated with Type 2 Diabetes in African Americans: The Atherosclerosis Risk in Communities Study. Diabetes, 51(1): 231-237.

  6. Dionne IJ, Garant MJ, Turner AN, Pollin T I, Lewis DG, Shuldiner AR, & Poehlman ET, (2002). Association between obesity and a polymorphism in the beta(1)-adrenoreceptor gene (Gly389Arg) in Caucasian women. Int. J. Obes. Relat. Metab. Disord., 26(5): 633-639.
  • Return to Division Faculty