Insulin and mTOR Pathway Regulate HDAC3-Mediated Deacetylation and Activation of PGK1

Phosphoglycerate kinase 1 (PGK1) catalyzes the reversible transfer of a phosphoryl group from 1, 3-bisphosphoglycerate (1, 3-BPG) to ADP, producing 3-phosphoglycerate (3-PG) and ATP. PGK1 plays a key role in coordinating glycolytic energy production with one-carbon metabolism, serine biosynthesis, and cellular redox regulation. Here, we report that PGK1 is acetylated at lysine 220 (K220), which inhibits PGK1 activity by disrupting the binding with its substrate, ADP. We have identified KAT9 and HDAC3 as the potential acetyltransferase and deacetylase, respectively, for PGK1. Insulin promotes K220 deacetylation to stimulate PGK1 activity. We show that the PI3K/AKT/mTOR pathway regulates HDAC3 S424 phosphorylation, which promotes HDAC3-PGK1 interaction and PGK1 K220 deacetylation. Our study uncovers a previously unknown mechanism for the insulin and mTOR pathway in regulation of glycolytic ATP production and cellular redox potential via HDAC3-mediated PGK1 deacetylation.Insulin and mTOR use acetylation state to regulate phosphoglycerate kinase, a key enzyme that coordinates the balance between energy production, biosynthesis, and redox potential.Author Summary: Phosphoglycerate kinase (PGK1) catalyzes the reversible phosphotransfer reaction from 1, 3-bisphosphoglycerate (1, 3-BPG) to ADP to form 3-phosphoglycerate (3-PG) and ATP. By controlling ATP and 3-PG levels, PGK1 plays an important role in coordinating energy production with biosynthesis and redox balance. In contrast to the extensive investigation of the transcriptional regulation of PGK1, little is known about its post-translational regulation. Here, we report that PGK1 is acetylated at lysine 220 (K220) and this acetylation inhibits PGK1 activity by disrupting the binding with its substrate, ADP. We have identified KAT9 and HDAC3 as the acetyltransferase and deacetylase, respectively, for PGK1. Moreover, we show there is molecular crosstalk between mTOR-mediated HDAC3 S424 phosphorylation and PGK1 K220 acetylation. Our study uncovers a previously unknown mechanism for the insulin and mTOR pathway in regulating glycolytic ATP production and cellular redox potential via HDAC3-mediated PGK1 deacetylation.