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Published on: December 23, 2022
Lipin-1 is a novel substrate of protein phosphatase PGAM5
Hiroko Okuno1, Haruna Okuzono1, Ayaka Hayase1
1Laboratory of Molecular Medicine, Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka, 565-0871, Japan.
Abstract:
Lipin-1 has multiple functions that regulate lipid and energy metabolism according to its subcellular localization. The subcellular localization of Lipin-1 is determined by kinase-dependent phosphorylation; however, the phosphatase that dephosphorylates and inactivates Lipin-1 has remained elusive. Using an immunoprecipitation and LC-MS/MS approach we have identified phosphoglycerate mutase family member 5 (PGAM5), a serine/threonine specific protein phosphatase, as a regulator of Lipin-1 activity. Treatment of human hepatocellular carcinoma cells with carbonyl cyanide m-chlorophenyl hydrazone (CCCP), which activates endogenous PGAM5, promoted dephosphorylation and nuclear accumulation of Lipin-1. Our findings further elucidate the molecular mechanisms that regulate Lipin-1.
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