Rehab Sciences 01/17/19
Congratulations on new publication, Skeletal Muscle Specific Knockout of DEP Domain-Containing 5 Increases mTORC1 Signaling, Muscle Cell Hypertrophy, and Mitochondrial Respiration by Ted G. Graber, Christopher S. Fry, Camille R. Brightwell, Tatiana Moro, Rosario Maroto, Nisha Bhattari, Craig Porter, Maki Wakamiya and Blake B. Rasmussen.
In this study, we knocked out the gene for DEPDC5, which is a subunit of the GATOR1 protein complex (a negative regulator of mTORC1—the master regulator of protein synthesis), in adult skeletal muscle in mice. GATOR1 shuts off protein synthesis in the cell when there are insufficient amino acids present. When we depleted DEPDC5, we determined a constitutive activation of mTORC1 leading to muscle hypertrophy increased mitochondrial respiration without functional improvements. Thus, we uncovered a role for DEPDC5/GATOR1 in the regulation of mitochondrial respiration, hinting that amino acid sensing apparatus in the cell may be more involved in metabolic programming than previously thought
Dr. Graber is a member of the Muscle Biology Laboratory team in the Center for Recovery, Physical Activity, and Nutrition and a postdoctoral trainee in the Division of Rehabilitation Sciences at UTMB.