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International Journal of Molecular... Oct 2022Phosphoglycerate mutase (PGAM) is a glycolytic enzyme converting 3-phosphoglycerate to 2-phosphoglycerate, which in mammalian cells is expressed in two isoforms: brain...
Phosphoglycerate mutase (PGAM) is a glycolytic enzyme converting 3-phosphoglycerate to 2-phosphoglycerate, which in mammalian cells is expressed in two isoforms: brain (PGAM1) and muscle (PGAM2). Recently, it was shown that besides its enzymatic function, PGAM2 can be imported to the cell nucleus where it co-localizes with the nucleoli. It was suggested that it functions there to stabilize the nucleolar structure, maintain mRNA expression, and assist in the assembly of new pre-ribosomal subunits. However, the precise mechanism by which the protein translocates to the nucleus is unknown. In this study, we present the first crystal structure of PGAM2, identify the residues involved in the nuclear localization of the protein and propose that PGAM contains a "quaternary nuclear localization sequence (NLS)", i.e., one that consists of residues from different protein chains. Additionally, we identify potential interaction partners for PGAM2 in the nucleoli and demonstrate that 14-3-3ζ/δ is indeed an interaction partner of PGAM2 in the nucleus. We also present evidence that the insulin/IGF1-PI3K-Akt-mTOR signaling pathway is responsible for the nuclear localization of PGAM2.
Topics: Animals; Phosphoglycerate Mutase; Active Transport, Cell Nucleus; Phosphatidylinositol 3-Kinases; 14-3-3 Proteins; Muscles; Mammals
PubMed: 36361985
DOI: 10.3390/ijms232113198 -
Toxicology Letters Jan 2023The pathophysiology of renal lipid toxicity caused by excess adiposity is not well-understood. Necroptosis, a regulated form of cell death, is involved in injuring renal...
The pathophysiology of renal lipid toxicity caused by excess adiposity is not well-understood. Necroptosis, a regulated form of cell death, is involved in injuring renal tubular epithelial cells (RTECs). Phosphoglycerate mutase 5 (PGAM5) is a key downstream effector of necroptosis. This study investigated the underlying mechanism of PGAM5 in promoting lipid-induced necroptosis in RTECs. HK2 cells (an immortalized proximal tubule epithelial cell line) were exposed to oleic acid (OA) to mimic the lipid overload environment in vitro. We found that OA suppressed HK2 cell proliferation, triggered cytoskeleton rupture and cell death. In OA-treated cells, upregulated expression of necroptosis pathway proteins, phosphorylated receptor-interacting protein-1/3 (pRIPK1/3), phosphorylated mixed lineage kinase domain-like protein (pMLKL), PGAM5, phosphorylated dynamin-related protein 1 (pDRP1), and downregulated pDRP1 expression were observed. This was accompanied by mitochondrial dysfunction (mitochondrial ROS overproduction and decreased mitochondrial membrane potential) and increased cellular necrosis, as reflected by Annexin V/ Propidium Iodide (PI) labeling. OA also induced the accumulation of LC3II and P62, blocking autophagosome fusion with lysosomes. Knockdown of PGAM5 could prevent these OA-induced changes. We propose inhibition of PGAM5 protects lipid-induced RTECs from necroptosis by reducing DRP1-mediated mitochondrial fission and improving mitophagy flux.
Topics: Mitophagy; Mitochondrial Dynamics; Necroptosis; Phosphoglycerate Mutase; Epithelial Cells; Lipids; Mitochondrial Proteins
PubMed: 36273635
DOI: 10.1016/j.toxlet.2022.10.003 -
International Journal of Molecular... Sep 2022Stressors cause activation of the hypothalamic-pituitary-adrenal (HPA) axis and a systemic inflammatory response. As a newly proposed cell death manner in recent years,...
Stressors cause activation of the hypothalamic-pituitary-adrenal (HPA) axis and a systemic inflammatory response. As a newly proposed cell death manner in recent years, necroptosis occurs in a variety of tissue damage and inflammation. However, the role of necroptosis in HPA axis activation remains to be elucidated. The aim of this study was to investigate the occurrence of necroptosis and its role in HPA activation in a porcine stress model induced by lipopolysaccharide (LPS). Several typical stress behaviors like fever, anorexia, shivering and vomiting were observed in piglets after LPS injection. HPA axis was activated as shown by increased plasma cortisol concentration and mRNA expression of pituitary corticotropin-releasing hormone receptor 1 () and adrenal steroidogenic acute regulatory protein (). The mRNA expression of tumor necrosis factor α (), interleukin-1β () and in the hypothalamus, pituitary gland and adrenal gland was elevated by LPS, accompanied by the activation of necroptosis indicated by higher mRNA expression of necroptosis signals including receptor-interacting protein kinase (RIP) 1, RIP3, and phosphorylated mixed-lineage kinase domain-like protein (MLKL). Furthermore, necrostatin-1 (Nec-1), an inhibitor of necroptosis, inhibited necroptosis indicated by decreased mRNA levels of , , , and phosphoglycerate mutase family member 5 () in the hypothalamus, pituitary gland and adrenal gland. Nec-1 also decreased the mRNA expression of and and inhibited the activation of the HPA axis indicated by lower plasma cortisol concentration and mRNA expression of adrenal type 2 melanocortin receptor () and . These findings suggest that necroptosis is present and contributes to HPA axis activation induced by LPS. These findings provide a potential possibility for necroptosis as an intervention target for alleviating HPA axis activation and stress responses.
Topics: Animals; Corticotropin-Releasing Hormone; Hydrocortisone; Hypothalamo-Hypophyseal System; Interleukin-1beta; Interleukin-6; Lipopolysaccharides; Necroptosis; Phosphoglycerate Mutase; Pituitary-Adrenal System; Protein Kinases; RNA, Messenger; Swine; Tumor Necrosis Factor-alpha
PubMed: 36232518
DOI: 10.3390/ijms231911218 -
Frontiers in Bioscience (Landmark... Sep 2022Enhanced glycolysis occurs in most human cancer cells and is related to chemoresistance. However, detailed mechanisms remain vague.
BACKGROUND
Enhanced glycolysis occurs in most human cancer cells and is related to chemoresistance. However, detailed mechanisms remain vague.
METHODS
Using proteinomics analysis, we found that the glycolytic enzyme Phosphoglycerate mutase 1 (PGAM1) was highly expressed in the paclitaxel-resistant ovarian cancer cell line SKOV3-TR30, as compared to its parental cell line SKOV3. Cell Counting Kit-8 proliferation experiment, plasmids and siRNA transfection, pyruvic acid and lactic acid production detection, immunofluorescence staining of functional mitochondria and oxygen consumption rate and extracellular acidification rate measurement were uesd to assess the glycolytic metabolism and paclitaxel resistance in ovarian cancer cells. The expression and prognostic effect of PGAM1 in 180 ovarian cancer patients were analyzed.
RESULTS
SKOV3-TR30 cells display higher glycolytic flux and lower mitochondrial function than SKOV3 cells. Down-regulation of PGAM1 in SKOV3-TR30 cells resulted in decreased paclitaxel resistance. Up-regulation of PGAM1 in SKOV3 cells led to enhanced paclitaxel resistance. Analysis of the glycolytic flux revealed that PGAM1-mediated pyruvic acid or lactic acid production could modulate the capabilities of ovarian cancer cell resistance to paclitaxel. Our data also show high expression of PGAM1 as significantly correlated with reduced overall survival and reduced progression free survival in ovarian cancer patients.
CONCLUSIONS
PGAM1 acts to promote paclitaxel resistance via pyruvic acid and/or lactate production in ovarian cancer cells. Inhibiting PGAM1 may provide a new approach to favorably alter paclitaxel resistance in ovarian cancer.
Topics: Cell Line, Tumor; Drug Resistance, Neoplasm; Female; Glycolysis; Humans; Lactic Acid; Ovarian Neoplasms; Paclitaxel; Phosphoglycerate Mutase; Pyruvic Acid; RNA, Small Interfering
PubMed: 36224008
DOI: 10.31083/j.fbl2709262 -
Journal of Biosciences 2022Gallbladder cancer (GBC) is one of the most fatal malignancies of the biliary tract system and is ranked sixth among the neoplasms of the gastrointestinal tract....
Gallbladder cancer (GBC) is one of the most fatal malignancies of the biliary tract system and is ranked sixth among the neoplasms of the gastrointestinal tract. Gallstone disease (GSD) is considered the major risk factor for GBC. However, the underlying molecular mechanism of GBC pathogenesis from different stages of GSD is not yet clearly understood. We analyzed transcriptomic datasets of GBC with reference to GSD of three different follow-up periods, i.e.,GBC vs. GSD3 (1-3 years), GBCvs. GSD5 (5-10 years), andGBC vs. GSD10 (more than 10 years). We identified overlapping and specific molecular signatures in GBC compared with GSD at three different follow-up periods. Using integrative network biology approaches, such as protein-protein interaction network analysis, transcriptional regulatory network analysis, and miRNA-target gene network analysis, we have identified a few hub genes. The hub genes identified from GBC vs. GSD3, GBC vs. GSD5, and GBC vs. GSD10 were directly or indirectly associated with cancer progression and initiation from GSD. Functional enrichment analysis indicated significant correlation between GSD and GBC pathogenesis. The identified hub genes can be used for future targeted validation to develop potential diagnostic, prognostic, or therapeutic biomarkers in GBC.
Topics: Cholelithiasis; Gallbladder Neoplasms; Humans; Kidney Diseases; MicroRNAs; Muscular Diseases; Phosphoglycerate Mutase
PubMed: 36222131
DOI: No ID Found -
Scientific Data Oct 2022We have previously shown that in Arabidopsis the three enzymes of lower glycolysis namely phosphoglycerate mutase (PGAM), enolase and pyruvate kinase form a complex...
We have previously shown that in Arabidopsis the three enzymes of lower glycolysis namely phosphoglycerate mutase (PGAM), enolase and pyruvate kinase form a complex which plays an important role in tethering the mitochondria to the chloroplast. Given that the metabolism of these mutants, the complemented of pgam mutant and overexpression lines of PGAM were unclear, here, we present gas chromatography mass spectrometry-based metabolomics data of them alongside their plant growth phenotypes. Compared with wild type, both sugar and amino acid concentration are significantly altered in phosphoglycerate mutase, enolase and pyruvate kinase. Conversely, overexpression of PGAM could decrease the content of 3PGA, sugar and several amino acids and increase the content of alanine and pyruvate. In addition, the pgam mutant could not be fully complemented by either a nuclear target pgam, a side-directed-mutate of pgam or a the E.coli PGAM in term of plant phenotype or metabolite profiles, suggesting the low glycolysis complete formation is required to support normal metabolism and growth.
Topics: Alanine; Amino Acids; Arabidopsis; Glycolysis; Phosphoglycerate Mutase; Phosphopyruvate Hydratase; Pyruvate Kinase; Pyruvates; Sugars
PubMed: 36220829
DOI: 10.1038/s41597-022-01673-z -
Frontiers in Veterinary Science 2022Spermatogenesis is a complex process involving a variety of intercellular interactions and precise regulation of gene expression. Spermatogenesis is sustained by a...
Spermatogenesis is a complex process involving a variety of intercellular interactions and precise regulation of gene expression. Spermatogenesis is sustained by a foundational Spermatogonial stem cells (SSCs) and in mammalian testis. Sertoli cells (SCs) are the major component of SSC niche. Sertoli cells provide structural support and supply energy substrate for developing germ cells. Phosphoglycerate mutase 1 (Pgam1) is a key enzyme in the glycolytic metabolism and our previous work showed that Pgam1 is expressed in SCs. In the present study, hypothesized that Pgam1-depedent glycolysis in SCs plays a functional role in regulating SSCs fate decisions. A co-culture system of murine SCs and primary spermatogonia was constructed to investigate the effects of Pgam1 knockdown or overexpression on SSCs proliferation and differentiation. Transcriptome results indicated that overexpression and knockdown of Pgam1 in SCs resulted in up-regulation of 458 genes (117 down-regulated, 341 up-regulated) and down-regulation of 409 genes (110 down-regulated, 299 up-regulated), respectively. Further analysis of these DEGs revealed that GDNF, FGF2 and other genes that serve key roles in SSCs niche maintenance were regulated by Pgam1. The metabolome results showed that a total of 11 and 16 differential metabolites were identified in the Pgam1 gene overexpression and knockdown respectively. Further screening of these metabolites indicated that Sertoli cell derived glutamate, glutamine, threonine, leucine, alanine, lysine, serine, succinate, fumarate, phosphoenolpyruvate, ATP, ADP, and AMP have potential roles in regulating SSCs proliferation and differentiation. In summary, this study established a SCs-SSCs co-culture system and identified a list of genes and small metabolic molecules that affect the proliferation and differentiation of SSCs. This study provides additional insights into the regulatory mechanisms underlying interactions between SCs and SSCs during mammalian spermatogenesis.
PubMed: 36213420
DOI: 10.3389/fvets.2022.992877 -
Journal of Clinical Laboratory Analysis Nov 2022To identify a novel marker for gastric cancer, we examined the usefulness of phosphoglycerate mutase 1 (PGAM1) as a potential diagnostic marker using isobaric tags for...
BACKGROUND
To identify a novel marker for gastric cancer, we examined the usefulness of phosphoglycerate mutase 1 (PGAM1) as a potential diagnostic marker using isobaric tags for relative and absolute quantitation (iTRAQ)-based quantitative proteomics and evaluated its clinical significance.
METHODS
Proteins from a discovery group of four paired gastric cancer tissues and adjacent gastric tissues were labeled with iTRAQ reagents and then identified and quantified using LC-MS/MS. The expression of PGAM1 was further validated in 139 gastric cancer patients using immunohistochemistry. Furthermore, the correlation of PGAM1 expression with clinical parameters was analyzed. Gene set enrichment analysis (GSEA) was performed to identify gene sets that were activated in PGAM1-overexpressing patients with gastric cancer.
RESULTS
PGAM1 was significantly overexpressed in most cancers but particularly so in gastric cancer, with a sensitivity of 82.01% (95% confidence interval [CI]: 75.5%-88.5%) and specificity of 79.13% (95% CI: 72.3%-86%). Its expression was significantly associated with histological grade II and III tumors (p = 0.033), lymph node metastasis (p = 0.031), and TNM III-IV staging (p = 0.025). The area under the receiver operating characteristic (ROC) curve for the detection of PGAM1 overexpression in gastric cancer was 0.718 (p < 0.01). Furthermore, GSEA revealed that several important pathways such as glycolysis pathway and immune pathways were significantly enriched in patients with gastric cancer with PGAM1 overexpression.
CONCLUSIONS
This study provided a sensitive method for detecting PGAM1, which may serve as a novel indicator for poor prognosis of gastric cancer, as well as a potent drug target for gastric cancer.
Topics: Humans; Phosphoglycerate Mutase; Stomach Neoplasms; Chromatography, Liquid; Tandem Mass Spectrometry; Glycolysis; Neoplasm Staging
PubMed: 36181311
DOI: 10.1002/jcla.24718 -
Parasite (Paris, France) 2022Schistosomiasis is a debilitating parasitic disease caused by intravascular flatworms called schistosomes (blood flukes) that affects >200 million people worldwide....
Schistosomiasis is a debilitating parasitic disease caused by intravascular flatworms called schistosomes (blood flukes) that affects >200 million people worldwide. Proteomic analysis has revealed the surprising presence of classical glycolytic enzymes - typically cytosolic proteins - located on the extracellular surface of the parasite tegument (skin). Immunolocalization experiments show that phosphoglycerate mutase (PGM) is widely expressed in parasite tissues and is highly expressed in the tegument. We demonstrate that live Schistosoma mansoni parasites express enzymatically active PGM on their tegumental surface. Suppression of PGM using RNA interference (RNAi) diminishes S. mansoni PGM (SmPGM) gene expression, protein levels, and surface enzyme activity. Sequence comparisons place SmPGM in the cofactor (2,3-bisphosphoglycerate)-dependent PGM (dPGM) family. We have produced recombinant SmPGM (rSmPGM) in an enzymatically active form in Escherichia coli. The Michaelis-Menten constant (K) of rSmPGM for its glycolytic substrate (3-phosphoglycerate) is 0.85 mM ± 0.02. rSmPGM activity is inhibited by the dPGM-specific inhibitor vanadate. Here, we show that rSmPGM not only binds to plasminogen but also promotes its conversion to an active form (plasmin) in vitro. This supports the hypothesis that host-interactive tegumental proteins (such as SmPGM), by enhancing plasmin formation, may help degrade blood clots around the worms in the vascular microenvironment and thus promote parasite survival in vivo.
Topics: Animals; Fibrinolysin; Host-Parasite Interactions; Humans; Phosphoglycerate Mutase; Proteomics; Schistosoma mansoni; Schistosomiasis
PubMed: 36083036
DOI: 10.1051/parasite/2022042 -
Revisited Metabolic Control and Reprogramming Cancers by Means of the Warburg Effect in Tumor Cells.International Journal of Molecular... Sep 2022Aerobic glycolysis is an emerging hallmark of many human cancers, as cancer cells are defined as a "metabolically abnormal system". Carbohydrates are metabolically... (Review)
Review
Aerobic glycolysis is an emerging hallmark of many human cancers, as cancer cells are defined as a "metabolically abnormal system". Carbohydrates are metabolically reprogrammed by its metabolizing and catabolizing enzymes in such abnormal cancer cells. Normal cells acquire their energy from oxidative phosphorylation, while cancer cells acquire their energy from oxidative glycolysis, known as the "Warburg effect". Energy-metabolic differences are easily found in the growth, invasion, immune escape and anti-tumor drug resistance of cancer cells. The glycolysis pathway is carried out in multiple enzymatic steps and yields two pyruvate molecules from one glucose (Glc) molecule by orchestral reaction of enzymes. Uncontrolled glycolysis or abnormally activated glycolysis is easily observed in the metabolism of cancer cells with enhanced levels of glycolytic proteins and enzymatic activities. In the "Warburg effect", tumor cells utilize energy supplied from lactic acid-based fermentative glycolysis operated by glycolysis-specific enzymes of hexokinase (HK), keto-HK-A, Glc-6-phosphate isomerase, 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase, phosphofructokinase (PFK), phosphor-Glc isomerase (PGI), fructose-bisphosphate aldolase, phosphoglycerate (PG) kinase (PGK)1, triose phosphate isomerase, PG mutase (PGAM), glyceraldehyde-3-phosphate dehydrogenase, enolase, pyruvate kinase isozyme type M2 (PKM2), pyruvate dehydrogenase (PDH), PDH kinase and lactate dehydrogenase. They are related to glycolytic flux. The key enzymes involved in glycolysis are directly linked to oncogenesis and drug resistance. Among the metabolic enzymes, PKM2, PGK1, HK, keto-HK-A and nucleoside diphosphate kinase also have protein kinase activities. Because glycolysis-generated energy is not enough, the cancer cell-favored glycolysis to produce low ATP level seems to be non-efficient for cancer growth and self-protection. Thus, the Warburg effect is still an attractive phenomenon to understand the metabolic glycolysis favored in cancer. If the basic properties of the Warburg effect, including genetic mutations and signaling shifts are considered, anti-cancer therapeutic targets can be raised. Specific therapeutics targeting metabolic enzymes in aerobic glycolysis and hypoxic microenvironments have been developed to kill tumor cells. The present review deals with the tumor-specific Warburg effect with the revisited viewpoint of recent progress.
Topics: Glycolysis; Hexokinase; Humans; Neoplasms; Phosphofructokinase-1; Phosphoglycerate Kinase; Phosphoglycerate Mutase; Pyruvates; Tumor Microenvironment
PubMed: 36077431
DOI: 10.3390/ijms231710037