instmctions): Diabetes is a major risk factor for cardiovascular disease, culminating in myocardial infarction, and heart failure. Prolonged hyper-0-GlcNAcylation, due to nutrient excess and hyperglycemia, is a major molecular cause of glucose toxicity and insulin resistance. Increased 0-GlcNAcylation directly contributes to diabetic cardiomyopathy and to dysfunctional mitochondria, perhaps contributing to excessive production of reactive oxygen species (ROS). Even though 0-GlcNAcylation clearly plays an important role in diabetic cardiovascular disease, virtually nothing is known about 0-GlcNAcylation in the cardiomyocyte. This project will elucidate the roles of 0-GlcNAc in diabetic cardiomyopathy and will define the """"""""0-GlcNAcome"""""""" of the cardiomyocyte at the site-specific level.
Specific Aims :
Aim 1 : Quantify the Site-Specific Crosstalk Between 0-GlcNAcylation and Phosphorylation in the cardiomyocyte proteome and in purified cardiomyocyte mitochondria from Normal and Diabetic Rats. Using chemico-enzymatic photocleavable tag enrichment combined with electron transfer dissociation (ETD) tandem mass spectrometry, we will quantify site occupancy for both 0-GlcNAc and phosphate in cardiomyocyte contractile and mitochondrial proteins from normal and diabetic rats.
Aim 2 : Determine the Specific Roles of 0-GlcNAcylation in normal cardiomyocyte mitochondria, and the sites of action and mechanisms of diabetes-induced dysfunction, leading to ROS production. We wilt specifically alter 0-GlcNAcylation using methods developed during the past 20-years, and correlate alterations with specific mitochondrial function.
Aim 3 : Elucidate the properties and regulation of cardiomyocyte mitochondrial isoforms of O-GlcNAc Transferase and 0-GlcNAcase. Virtually nothing is known about the mitochondrial isoforms of 0-GlcNAc Transferase (OGT) or 0-GlcNAcase (OGA). We will elucidate their localization, activities, molecular associations and kinetic activities in mitochondria from normal and diabetic rats.
Aim 4 : Evaluate the affects and roles of diabetes-induced mitochondrial dysfunction and increased O- GlcNAcylation of cardiomyocyte contractile machinery on cardiac physiology and function. Working closely with Core D we will systematically evaluate the importance of the crosstalk between 0-GlcNAcylation and phosphorylation of cardiomyocyte contractile and mitochondrial proteins on the physiological functions of cardiomyocytes These studies will open a new paradigm for understanding the regulation of cardiac functions and in diabetic cardiomyopathies. They will lead to totally unexplored avenues of possible therapeutic interventions
Diabetes is a major epidemic and contributes to cardiovascular disease, which ultimately results in heart failure or myocardial infarction. Increased 0-GlcNAcylation, a sugar post-translational modification, underlies molecular events contributing to diabetic cardiomyopathies by affecting the functions of contractile and mitochondrial proteins within the cardiomyocyte. These studies will elucidate the importance of O- GlcNAc in both normal and diabetic cardiomyocyte physiology, and will possibly lead to novel treatments.
|Yang, Shuang; Rubin, Abigail; Eshghi, Shadi Toghi et al. (2016) Chemoenzymatic method for glycomics: Isolation, identification, and quantitation. Proteomics 16:241-56|
|Lam, Maggie P Y; Venkatraman, Vidya; Xing, Yi et al. (2016) Data-Driven Approach To Determine Popular Proteins for Targeted Proteomics Translation of Six Organ Systems. J Proteome Res 15:4126-4134|
|Fahie, Kamau; Zachara, Natasha E (2016) Molecular Functions of Glycoconjugates in Autophagy. J Mol Biol 428:3305-24|
|Yang, Weiming; Jackson, Brooks; Zhang, Hui (2016) Identification of glycoproteins associated with HIV latently infected cells using quantitative glycoproteomics. Proteomics 16:1872-80|
|HardivillÃ©, StÃ©phan; Hart, Gerald W (2016) Nutrient regulation of gene expression by O-GlcNAcylation of chromatin. Curr Opin Chem Biol 33:88-94|
|Miller, William P; Mihailescu, Maria L; Yang, Chen et al. (2016) The Translational Repressor 4E-BP1 Contributes to Diabetes-Induced Visual Dysfunction. Invest Ophthalmol Vis Sci 57:1327-37|
|Zhu, Yanping; Liu, Ta-Wei; Madden, Zarina et al. (2016) Post-translational O-GlcNAcylation is essential for nuclear pore integrity and maintenance of the pore selectivity filter. J Mol Cell Biol 8:2-16|
|Hou, Ching-Wen; Mohanan, Vishnu; Zachara, Natasha E et al. (2016) Identification and biological consequences of the O-GlcNAc modification of the human innate immune receptor, Nod2. Glycobiology 26:13-8|
|Ma, Junfeng; Hart, Gerald W (2016) Mass Spectrometry-Based Quantitative O-GlcNAcomic Analysis. Methods Mol Biol 1410:91-103|
|LagerlÃ¶f, Olof; Slocomb, Julia E; Hong, Ingie et al. (2016) The nutrient sensor OGT in PVN neurons regulates feeding. Science 351:1293-6|
Showing the most recent 10 out of 110 publications