SIRT5 Regulates both Cytosolic and Mitochondrial Protein Malonylation with Glycolysis as a Major Target

Abstract

SUMMARY Protein acylation links energetic substrate flux with cellular adaptive responses. SIRT5 is a NAD+-dependent lysine deacylase and removes both succinyl and malonyl groups. Using affinity enrichment and label free quantitative proteomics, we characterized the SIRT5-regulated lysine malonylome in wild-type (WT) and Sirt5−/− mice. 1,137 malonyllysine sites were identified across 430 proteins, with 183 sites (from 120 proteins) significantly increased in Sirt5−/− animals. Pathway analysis identified glycolysis as the top SIRT5-regulated pathway. Importantly, glycolytic flux was diminished in primary hepatocytes from Sirt5−/− compared to WT mice. Substitution of malonylated lysine residue 184 in glyceraldehyde 3-phosphate dehydrogenase with glutamic acid, a malonyllysine mimic, suppressed its enzymatic activity. Comparison with our previous reports on acylation reveals that malonylation targets a different set of proteins than acetylation and succinylation. These data demonstrate that SIRT5 is a global regulator of lysine malonylation and provide a mechanism for regulation of energetic flux through glycolysis.

SHMT2 Desuccinylation by SIRT5 Drives Cancer Cell Proliferation

“…It controls fatty acid oxidation through desuccinylating 3-hydroxy-3-methylglutaryl-CoA synthase 2 (HMGCS2), enoyl-CoA hydratase a-subunit (ECHA), and demalonylating malonyl-CoA decarboxylase (26)(27)(28). It also functions in glycolysis and TCA cycle by controlling the PTM level of succinate dehydrogenase complex (GDH), pyruvate dehydrogenase complex (PDH), and GAPDH (29,30). In response to oxidative stress, SIRT5 desuccinylates superoxide dismutase [Cu-Zn] (SOD1), isocitrate dehydrogenase 2 (IDH2), and deglutarylates glucose-6-phosphate 1-dehydrogenase (G6PD) to maintain cellular redox homeostasis (31,32).…”

Sirtuin 5: a review of structure, known inhibitors and clues for developing new inhibitors

“…SIRT1-3 have been well studied for decades (Bell and Guarente, 2011;Donmez and Outeiro, 2013;Mellini et al, 2015), whereas SIRT4-7 have received relatively little attention until recently. SIRT5 has become an active topic of research towards its biological and physiological functions (Du et al, 2011;Nishida et al, 2015;Polletta et al, 2015;Tan et al, 2014). Several studies have demonstrated that SIRT5 actually has relatively weak deacetylase activity comparing with other sirtuins.…”

Structure‐based discovery of new selective small‐molecule sirtuin 5 inhibitors

“…Finally, 20 hit compounds ( Figure 1) were selected for subsequent biochemical test; to the best of our knowledge, all of these compounds have not been reported as sirtuin inhibitors so far. The predicted binding modes of the selected compounds (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20) are shown in Figure 1. We observed that although these compounds may have different binding modes with SIRT5, all of them are likely to form hydrogen-bonding/electrostatic interactions with Tyr102 and Arg105 (Figure 1).…”

“…[1,2,[11][12][13] SIRT5, which mainly localizes in the mitochondrial matrix and preferentially hydrolyzes acidic acyl modifications, was found to play a pivotal role in mitochondrial metabolism, for example, amino acid degradation, the tricarboxylic acid cycle, and fatty acid metabolism. [14,15] Park et al recently revealed that SIRT5 represses biochemical activity of, and cellular respiration through, pyruvate dehydrogenase complex (PDC) and succinate dehydrogenase (SDH) [14] ; dysregulated PDC or SDH activity is linked to type 2 diabetes and cancer. [13,[16][17][18] Another study showed that SIRT5 could positively regulate glycolysis via demalonylation of glycolytic enzymes, providing a possible link to cancer metabolism.…”

“…[13,[16][17][18] Another study showed that SIRT5 could positively regulate glycolysis via demalonylation of glycolytic enzymes, providing a possible link to cancer metabolism. [15,19] Lu et al found that SIRT5 is overexpressed in human non-small-cell lung cancer and associated with poor outcomes. [20] All of these studies indicate that SIRT5 is likely a potential molecular target for the treatment of metabolism-related disorders through interference with enzymes involved in metabolism pathways.…”