R. Mark Payne, MD
Primary Appointment: Professor of Pediatrics (Division of Cardiology)
Professor of Medical and Molecular Genetics
Professor of Cellular & Integrative Physiology
Director MS Program in Translational Research, CTSI
- BS:Washington & Lee University
- MD:University of Texas (Houston)
- Pediatric Residency and Chief Resident: St. Louis Children’s Hospital, Washington University, St. Louis
- Fellowship (Pediatric Cardiology): St. Louis Children’s Hospital, Washington University, St. Louis
- Postdoctorate: Washington University, St. Louis
The goal of my research is to understand the mechanism(s) underlying metabolic cardiomyopathies of childhood and young adults, and to develop therapies for them. The focus of our lab has been on Friedreich’s Ataxia (FRDA), which is a progressive mitochondrial disorder that causes a severe hypertrophic cardiomyopathy, heart failure, and neuropathy in children and young adults. In this regard, our work has recently been directed at: 1) understanding the basic mechanism(s) whereby loss of frataxin in cardiac mitochondria causes heart failure, 2) developing therapeutic approaches to treating both the heart failure and the neurologic dysfunction of FRDA, and 3) understanding the clinical cardiomyopathy of FRDA, which is unlike the hypertrophic cardiomyopathies typically seen in adult heart disease. We are currently trying to understand the role of mitochondrial protein acetylation in regulation of metabolism in the normal and cardiomyopathic heart. To achieve our goals, we use a combination of biochemistry, molecular and protein biology, and genetically altered mice in the laboratory. These studies are combined with clinical trials and patient data to generate a ‘bench to bedside’ understanding of disease progression in children. Current projects in the lab include:
- Role of mitochondrial protein acetylation on cardiac metabolism and function. The loss of frataxin in the FRDA heart causes extensive mitochondrial protein acetylation resulting in loss of energy generation and cardiomyopathy. This project makes heavy use of genetically altered mice, cardiac physiology, and mouse echocardiography.
- Development of cell penetrant peptides for enzyme replacement therapy of mitochondrial proteins. We have developed a cell penetrant mitochondrial-targeting peptide that will deliver a protein cargo to mitochondria in vivo. This project makes heavy use of molecular biology, protein expression and purification, and genetically altered mice.
- Identification and development of cardiac specific biomarkers for children with cardiomyopathy. This project makes extensive use of clinically derived patient reagents (blood) and data, investigative imaging technologies (PET scanning), and basic laboratory technologies.
- Understanding cell signaling events in FRDA. This project makes extensive use of cell culture to determine relevant gene expression profiles in fibroblasts and IPS cells from patients with FRDA.
- Intermediate filament phosphorylation in Giant Axonal Neuropathy. This project studies the RAS signaling pathway in a rare neurologic disease of childhood, Giant Axonal Neuropathy. Extensive cell culture of human fibroblasts, and molecular biology techniques are used in this project.
A key objective in the lab is to develop collaborations that will more rapidly advance our understanding of the basic events underlying the cardiomyopathy of FRDA, and lead to new treatment and diagnostic paradigms for rare diseases of childhood.