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.
|Ma, Junfeng; Hart, Gerald W (2017) Analysis of Protein O-GlcNAcylation by Mass Spectrometry. Curr Protoc Protein Sci 87:24.10.1-24.10.16|
|Zhou, Jianliang; Yang, Weiming; Hu, Yingwei et al. (2017) Site-Specific Fucosylation Analysis Identifying Glycoproteins Associated with Aggressive Prostate Cancer Cell Lines Using Tandem Affinity Enrichments of Intact Glycopeptides Followed by Mass Spectrometry. Anal Chem 89:7623-7630|
|Yang, Shuang; Zhang, Lei; Thomas, Stefani et al. (2017) Modification of Sialic Acids on Solid Phase: Accurate Characterization of Protein Sialylation. Anal Chem 89:6330-6335|
|Lagerlöf, Olof; Hart, Gerald W; Huganir, Richard L (2017) O-GlcNAc transferase regulates excitatory synapse maturity. Proc Natl Acad Sci U S A 114:1684-1689|
|Grima, Jonathan C; Daigle, J Gavin; Arbez, Nicolas et al. (2017) Mutant Huntingtin Disrupts the Nuclear Pore Complex. Neuron 94:93-107.e6|
|Martinez, Marissa R; Dias, Thiago Braido; Natov, Peter S et al. (2017) Stress-induced O-GlcNAcylation: an adaptive process of injured cells. Biochem Soc Trans 45:237-249|
|Cho, Gun-Sik; Lee, Dong I; Tampakakis, Emmanouil et al. (2017) Neonatal Transplantation Confers Maturation of PSC-Derived Cardiomyocytes Conducive to Modeling Cardiomyopathy. Cell Rep 18:571-582|
|Groves, Jennifer A; Maduka, Austin O; O'Meally, Robert N et al. (2017) Fatty acid synthase inhibits the O-GlcNAcase during oxidative stress. J Biol Chem 292:6493-6511|
|Yang, Shuang; Clark, David; Liu, Yang et al. (2017) High-throughput analysis of N-glycans using AutoTip via glycoprotein immobilization. Sci Rep 7:10216|
|Geno, K Aaron; Bush, C Allen; Wang, Mengnan et al. (2017) WciG O-Acetyltransferase Functionality Differentiates Pneumococcal Serotypes 35C and 42. J Clin Microbiol 55:2775-2784|
Showing the most recent 10 out of 128 publications