Biomaterial Database

O-GlcNAc modification of leucyl-tRNA synthetase 1 integrates leucine and glucose availability to regulate mTORC1 and the metabolic fate of leucine. 2022

Kibum Kim, and Hee Chan Yoo, and Byung Gyu Kim, and Sulhee Kim, and Yulseung Sung, and Ina Yoon, and Ya Chun Yu, and Seung Joon Park, and Jong Hyun Kim, and Kyungjae Myung, and Kwang Yeon Hwang, and Sunghoon Kim, and Jung Min Han

Interdisciplinary Program of Integrated OMICS for Biomedical Science, Graduate School, Yonsei University, Seoul, 03722, South Korea.

All living organisms have the ability to sense nutrient levels to coordinate cellular metabolism. Despite the importance of nutrient-sensing pathways that detect the levels of amino acids and glucose, how the availability of these two types of nutrients is integrated is unclear. Here, we show that glucose availability regulates the central nutrient effector mTORC1 through intracellular leucine sensor leucyl-tRNA synthetase 1 (LARS1). Glucose starvation results in O-GlcNAcylation of LARS1 on residue S1042. This modification inhibits the interaction of LARS1 with RagD GTPase and reduces the affinity of LARS1 for leucine by promoting phosphorylation of its leucine-binding site by the autophagy-activating kinase ULK1, decreasing mTORC1 activity. The lack of LARS1 O-GlcNAcylation constitutively activates mTORC1, supporting its ability to sense leucine, and deregulates protein synthesis and leucine catabolism under glucose starvation. This work demonstrates that LARS1 integrates leucine and glucose availability to regulate mTORC1 and the metabolic fate of leucine.

UI	MeSH Term	Description	Entries
D007930	Leucine	An essential branched-chain amino acid important for hemoglobin formation.	L-Leucine,Leucine, L-Isomer,L-Isomer Leucine,Leucine, L Isomer
D007935	Leucine-tRNA Ligase	An enzyme that activates leucine with its specific transfer RNA. EC 6.1.1.4.	Leucyl T RNA Synthetase,Leu-tRNA Ligase,Leucine-tRNA Synthetase,Leu tRNA Ligase,Leucine tRNA Ligase,Leucine tRNA Synthetase,Ligase, Leu-tRNA,Ligase, Leucine-tRNA,Synthetase, Leucine-tRNA
D005947	Glucose	A primary source of energy for living organisms. It is naturally occurring and is found in fruits and other parts of plants in its free state. It is used therapeutically in fluid and nutrient replacement.	Dextrose,Anhydrous Dextrose,D-Glucose,Glucose Monohydrate,Glucose, (DL)-Isomer,Glucose, (alpha-D)-Isomer,Glucose, (beta-D)-Isomer,D Glucose,Dextrose, Anhydrous,Monohydrate, Glucose
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000076222	Mechanistic Target of Rapamycin Complex 1	An evolutionarily conserved multiprotein complex that functions as a cellular energy sensor and regulator of protein synthesis for cell growth and proliferation. It consists of TOR SERINE-THREONINE KINASES; REGULATORY-ASSOCIATED PROTEIN OF MTOR (RAPTOR); MLST8 PROTEIN; and AKT1 substrate 1 protein. The activity of the complex is regulated by SIROLIMUS; INSULIN; GROWTH FACTORS; PHOSPHATIDIC ACIDS; some amino acids or amino acid derivatives, and OXIDATIVE STRESS.	TOR Complex 1,TORC1,Target of Rapamycin Complex 1,mTORC1,mTORC1 Complex,Complex, mTORC1
D000117	Acetylglucosamine	The N-acetyl derivative of glucosamine.	Acetyl Glucosamine,N-Acetyl Glucosamine,N-Acetyl-beta-D-Glucosamine,N-Acetylglucosamine,beta-N-Acetylglucosamine,2-Acetamido-2-Deoxy-D-Glucose,2-Acetamido-2-Deoxyglucose,N-Acetyl-D-Glucosamine,2 Acetamido 2 Deoxy D Glucose,2 Acetamido 2 Deoxyglucose,Glucosamine, Acetyl,Glucosamine, N-Acetyl,N Acetyl D Glucosamine,N Acetyl Glucosamine,N Acetyl beta D Glucosamine,N Acetylglucosamine,beta N Acetylglucosamine
D001343	Autophagy	The segregation and degradation of various cytoplasmic constituents via engulfment by MULTIVESICULAR BODIES; VACUOLES; or AUTOPHAGOSOMES and their digestion by LYSOSOMES. It plays an important role in BIOLOGICAL METAMORPHOSIS and in the removal of bone by OSTEOCLASTS. Defective autophagy is associated with various diseases, including NEURODEGENERATIVE DISEASES and cancer.	Autophagocytosis,ER-Phagy,Lipophagy,Nucleophagy,Reticulophagy,Ribophagy,Autophagy, Cellular,Cellular Autophagy,ER Phagy