-
Proceedings of the National Academy of... Jan 2022Cells are continuously exposed to potentially dangerous compounds. Progressive accumulation of damage is suspected to contribute to neurodegenerative diseases and aging,...
Cells are continuously exposed to potentially dangerous compounds. Progressive accumulation of damage is suspected to contribute to neurodegenerative diseases and aging, but the molecular identity of the damage remains largely unknown. Here we report that PARK7, an enzyme mutated in hereditary Parkinson's disease, prevents damage of proteins and metabolites caused by a metabolite of glycolysis. We found that the glycolytic metabolite 1,3-bisphosphoglycerate (1,3-BPG) spontaneously forms a novel reactive intermediate that avidly reacts with amino groups. PARK7 acts by destroying this intermediate, thereby preventing the formation of proteins and metabolites with glycerate and phosphoglycerate modifications on amino groups. As a consequence, inactivation of PARK7 (or its orthologs) in human cell lines, mouse brain, and leads to the accumulation of these damaged compounds, most of which have not been described before. Our work demonstrates that PARK7 function represents a highly conserved strategy to prevent damage in cells that metabolize carbohydrates. This represents a fundamental link between metabolism and a type of cellular damage that might contribute to the development of Parkinson's disease.
Topics: Animals; Biomarkers; Carbohydrate Metabolism; Chromatography, Liquid; Drosophila melanogaster; Gene Knockdown Techniques; Glucose; Glyceric Acids; Glycolysis; Humans; Mass Spectrometry; Metabolic Networks and Pathways; Metabolome; Metabolomics; Mice; Parkinson Disease; Protein Deglycase DJ-1
PubMed: 35046029
DOI: 10.1073/pnas.2111338119 -
Molecular Cell Aug 2023Ubiquitin-dependent control of mitochondrial dynamics is important for protein quality and neuronal integrity. Mitofusins, mitochondrial fusion factors, can integrate...
Ubiquitin-dependent control of mitochondrial dynamics is important for protein quality and neuronal integrity. Mitofusins, mitochondrial fusion factors, can integrate cellular stress through their ubiquitylation, which is carried out by multiple E3 enzymes in response to many different stimuli. However, the molecular mechanisms that enable coordinated responses are largely unknown. Here we show that yeast Ufd2, a conserved ubiquitin chain-elongating E4 enzyme, is required for mitochondrial shape adjustments. Under various stresses, Ufd2 translocates to mitochondria and triggers mitofusin ubiquitylation. This elongates ubiquitin chains on mitofusin and promotes its proteasomal degradation, leading to mitochondrial fragmentation. Ufd2 and its human homologue UBE4B also target mitofusin mutants associated with Charcot-Marie-Tooth disease, a hereditary sensory and motor neuropathy characterized by progressive loss of the peripheral nerves. This underscores the pathophysiological importance of E4-mediated ubiquitylation in neurodegeneration. In summary, we identify E4-dependent mitochondrial stress adaptation by linking various metabolic processes to mitochondrial fusion and fission dynamics.
Topics: Humans; Acclimatization; Mitochondria; Saccharomyces cerevisiae; Ubiquitin; Ubiquitin-Protein Ligases; Ubiquitination; Mitochondrial Proteins
PubMed: 37595558
DOI: 10.1016/j.molcel.2023.07.021 -
Structural basis of ER-associated protein degradation mediated by the Hrd1 ubiquitin ligase complex.Science (New York, N.Y.) Apr 2020Misfolded luminal endoplasmic reticulum (ER) proteins undergo ER-associated degradation (ERAD-L): They are retrotranslocated into the cytosol, polyubiquitinated, and...
Misfolded luminal endoplasmic reticulum (ER) proteins undergo ER-associated degradation (ERAD-L): They are retrotranslocated into the cytosol, polyubiquitinated, and degraded by the proteasome. ERAD-L is mediated by the Hrd1 complex (composed of Hrd1, Hrd3, Der1, Usa1, and Yos9), but the mechanism of retrotranslocation remains mysterious. Here, we report a structure of the active Hrd1 complex, as determined by cryo-electron microscopy analysis of two subcomplexes. Hrd3 and Yos9 jointly create a luminal binding site that recognizes glycosylated substrates. Hrd1 and the rhomboid-like Der1 protein form two "half-channels" with cytosolic and luminal cavities, respectively, and lateral gates facing one another in a thinned membrane region. These structures, along with crosslinking and molecular dynamics simulation results, suggest how a polypeptide loop of an ERAD-L substrate moves through the ER membrane.
Topics: Carrier Proteins; Cryoelectron Microscopy; Endoplasmic Reticulum; Endoplasmic Reticulum-Associated Degradation; Membrane Glycoproteins; Membrane Proteins; Molecular Dynamics Simulation; Multiprotein Complexes; Protein Domains; Protein Folding; Proteolysis; Saccharomyces cerevisiae Proteins; Ubiquitin-Protein Ligases
PubMed: 32327568
DOI: 10.1126/science.aaz2449 -
Open Biology Mar 2021-palmitoylation is a reversible posttranslational lipid modification of proteins. It controls protein activity, stability, trafficking and protein-protein interactions.... (Review)
Review
-palmitoylation is a reversible posttranslational lipid modification of proteins. It controls protein activity, stability, trafficking and protein-protein interactions. Recent global profiling of immune cells and targeted analysis have identified many -palmitoylated immunity-associated proteins. Here, we review -palmitoylated immune receptors and effectors, and their dynamic regulation at cellular membranes to generate specific and balanced immune responses. We also highlight how this understanding can drive therapeutic advances to pharmacologically modulate immune responses.
Topics: Adaptive Immunity; Animals; Humans; Immunity, Innate; Lipoylation; Protein Processing, Post-Translational; Receptors, Immunologic
PubMed: 33653086
DOI: 10.1098/rsob.200411 -
Nature Reviews. Molecular Cell Biology Jun 2024Over the past two decades, protein S-acylation (often referred to as S-palmitoylation) has emerged as an important regulator of vital signalling pathways. S-Acylation is... (Review)
Review
Over the past two decades, protein S-acylation (often referred to as S-palmitoylation) has emerged as an important regulator of vital signalling pathways. S-Acylation is a reversible post-translational modification that involves the attachment of a fatty acid to a protein. Maintenance of the equilibrium between protein S-acylation and deacylation has demonstrated profound effects on various cellular processes, including innate immunity, inflammation, glucose metabolism and fat metabolism, as well as on brain and heart function. This Review provides an overview of current understanding of S-acylation and deacylation enzymes, their spatiotemporal regulation by sophisticated multilayered mechanisms, and their influence on protein function, cellular processes and physiological pathways. Furthermore, we examine how disruptions in protein S-acylation are associated with a broad spectrum of diseases from cancer to autoinflammatory disorders and neurological conditions.
Topics: Humans; Animals; Acylation; Protein Processing, Post-Translational; Signal Transduction; Lipoylation; Proteins
PubMed: 38355760
DOI: 10.1038/s41580-024-00700-8 -
Molecular Cell Jan 2022Acetyl-CoA is a key intermediate situated at the intersection of many metabolic pathways. The reliance of histone acetylation on acetyl-CoA enables the coordination of...
Acetyl-CoA is a key intermediate situated at the intersection of many metabolic pathways. The reliance of histone acetylation on acetyl-CoA enables the coordination of gene expression with metabolic state. Abundant acetyl-CoA has been linked to the activation of genes involved in cell growth or tumorigenesis through histone acetylation. However, the role of histone acetylation in transcription under low levels of acetyl-CoA remains poorly understood. Here, we use a yeast starvation model to observe the dramatic alteration in the global occupancy of histone acetylation following carbon starvation; the location of histone acetylation marks shifts from growth-promoting genes to gluconeogenic and fat metabolism genes. This reallocation is mediated by both the histone deacetylase Rpd3p and the acetyltransferase Gcn5p, a component of the SAGA transcriptional coactivator. Our findings reveal an unexpected switch in the specificity of histone acetylation to promote pathways that generate acetyl-CoA for oxidation when acetyl-CoA is limiting.
Topics: Acetyl Coenzyme A; Acetylation; Gene Expression Regulation, Fungal; Gluconeogenesis; Glucose; Histone Acetyltransferases; Histone Deacetylases; Histones; Lipid Metabolism; Protein Processing, Post-Translational; Saccharomyces cerevisiae; Saccharomyces cerevisiae Proteins; Trans-Activators
PubMed: 34995509
DOI: 10.1016/j.molcel.2021.12.015 -
Molecular Medicine (Cambridge, Mass.) Jul 2023The metabolism of glucose and lipids is essential for energy production in the body, and dysregulation of the metabolic pathways of these molecules is implicated in... (Review)
Review
The metabolism of glucose and lipids is essential for energy production in the body, and dysregulation of the metabolic pathways of these molecules is implicated in various acute and chronic diseases, such as type 2 diabetes, Alzheimer's disease, atherosclerosis (AS), obesity, tumor, and sepsis. Post-translational modifications (PTMs) of proteins, which involve the addition or removal of covalent functional groups, play a crucial role in regulating protein structure, localization function, and activity. Common PTMs include phosphorylation, acetylation, ubiquitination, methylation, and glycosylation. Emerging evidence indicates that PTMs are significant in modulating glucose and lipid metabolism by modifying key enzymes or proteins. In this review, we summarize the current understanding of the role and regulatory mechanisms of PTMs in glucose and lipid metabolism, with a focus on their involvement in disease progression associated with aberrant metabolism. Furthermore, we discuss the future prospects of PTMs, highlighting their potential for gaining deeper insights into glucose and lipid metabolism and related diseases.
Topics: Humans; Glucose; Lipid Metabolism; Diabetes Mellitus, Type 2; Protein Processing, Post-Translational; Phosphorylation; Proteins
PubMed: 37415097
DOI: 10.1186/s10020-023-00684-9 -
Current Opinion in Chemical Biology Dec 2022Protein S-glutathionylation serves a regulatory role in proteins and modulates distinct biological processes implicated in health and diseases. Despite challenges in... (Review)
Review
Protein S-glutathionylation serves a regulatory role in proteins and modulates distinct biological processes implicated in health and diseases. Despite challenges in analyzing the dynamic and reversible nature of S-glutathionylation, recent chemical and biological methods have significantly advanced the field of S-glutathionylation, culminating in selective identification and detection, structural motif analysis, and functional studies of S-glutathionylation. This review will highlight emerging studies of protein glutathionylation, beginning by introducing biochemical tools that enable mass spectrometric identification and live-cell imaging of S-glutathionylation. Next, it will spotlight recent examples of S-glutathionylation regulating physiology and inflammation. Lastly, we will feature two emerging lines of glutathionylation research in cryptic cysteine glutathionylation and protein C-glutathionylation.
Topics: Glutathione; Oxidation-Reduction; Cysteine; Proteins; Protein Processing, Post-Translational; Biology
PubMed: 36223700
DOI: 10.1016/j.cbpa.2022.102221 -
Plant Signaling & Behavior Mar 2021Gamma-aminobutyric acid (GABA) is a ubiquitous four-carbon, non-protein amino acid. GABA has been widely studied in animal central nervous systems, where it acts as an... (Review)
Review
Gamma-aminobutyric acid (GABA) is a ubiquitous four-carbon, non-protein amino acid. GABA has been widely studied in animal central nervous systems, where it acts as an inhibitory neurotransmitter. In plants, it is metabolized through the GABA shunt pathway, a bypass of the tricarboxylic acid (TCA) cycle. Additionally, it can be synthesized through the polyamine metabolic pathway. GABA acts as a signal in -mediated plant gene transformation and in plant development, especially in pollen tube elongation (to enter the ovule), root growth, fruit ripening, and seed germination. It is accumulated during plant responses to environmental stresses and pathogen and insect attacks. A high concentration of GABA elevates plant stress tolerance by improving photosynthesis, inhibiting reactive oxygen species (ROS) generation, activating antioxidant enzymes, and regulating stomatal opening in drought stress. The transporters of GABA in plants are reviewed in this work. We summarize the recent research on GABA function and transporters with the goal of providing a review of GABA in plants.
Topics: GABA Plasma Membrane Transport Proteins; Metabolic Networks and Pathways; Plants; Signal Transduction; Stress, Physiological; gamma-Aminobutyric Acid
PubMed: 33404284
DOI: 10.1080/15592324.2020.1862565 -
Biochimica Et Biophysica Acta. Gene... Feb 2021Histone post-translational modifications are essential for the regulation of gene expression in eukaryotes. Gcn5 (KAT2A) is a histone acetyltransferase that catalyzes... (Review)
Review
Histone post-translational modifications are essential for the regulation of gene expression in eukaryotes. Gcn5 (KAT2A) is a histone acetyltransferase that catalyzes the post-translational modification at multiple positions of histone H3 through the transfer of acetyl groups to the free amino group of lysine residues. Gcn5 catalyzes histone acetylation in the context of a HAT module containing the Ada2, Ada3 and Sgf29 subunits of the parent megadalton SAGA transcriptional coactivator complex. Biochemical and structural studies have elucidated mechanisms for Gcn5's acetyl- and other acyltransferase activities on histone substrates, for histone H3 phosphorylation and histone H3 methylation crosstalks with histone H3 acetylation, and for how Ada2 increases Gcn5's histone acetyltransferase activity. Other studies have identified Ada2 isoforms in SAGA-related complexes and characterized variant Gcn5 HAT modules containing these Ada2 isoforms. In this review, we highlight biochemical and structural studies of Gcn5 and its functional interactions with Ada2, Ada3 and Sgf29.
Topics: Acetylation; Cryoelectron Microscopy; Histone Acetyltransferases; Histones; Isoenzymes; Methylation; Multienzyme Complexes; Phosphorylation; Protein Processing, Post-Translational; Saccharomyces cerevisiae Proteins; Transcription Factors; p300-CBP Transcription Factors
PubMed: 32890768
DOI: 10.1016/j.bbagrm.2020.194629