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Critical Reviews in Biotechnology Dec 2021Chalcones and the subsequently generated flavonoids, as well as flavonoid derivatives, have been proven to have a variety of physiological activities and are widely used... (Review)
Review
Chalcones and the subsequently generated flavonoids, as well as flavonoid derivatives, have been proven to have a variety of physiological activities and are widely used in: the pharmaceutical, food, feed, and cosmetic industries. As the content of chalcones and downstream products in native plants is low, the production of these compounds by microorganisms has gained the attention of many researchers and has a history of more than 20 years. The mining and engineering of chalcone synthase (CHS) could be one of the most important ways to achieve more efficient production of chalcones and downstream products in microorganisms. CHS has a broad spectrum of substrates, and its enzyme activity and expression level can significantly affect the efficiency of the biosynthesis of flavonoids. This review summarizes the recent advances in the: structure, mechanism, evolution, substrate spectrum, transformation, and expression regulation in the flavonoid biosynthesis of this vital enzyme. Future development directions were also suggested. The findings may further promote the research and development of flavonoids and health products, making them vital in the fields of human diet and health.
Topics: Acyltransferases; Flavonoids; Humans; Plants
PubMed: 33980085
DOI: 10.1080/07388551.2021.1922350 -
The Journal of Biological Chemistry 2021Brassinosteroids (BRs) are steroid hormones of plants that coordinate fundamental growth and development processes. Their homeostasis is controlled by diverse means,...
Brassinosteroids (BRs) are steroid hormones of plants that coordinate fundamental growth and development processes. Their homeostasis is controlled by diverse means, including glucosylation of the bioactive BR brassinolide (BL), which is catalyzed by the UDP-glycosyltransferases (UGTs) UGT73C5 and UGT73C6 and occurs mainly at the C-23 position. Additional evidence had suggested that the resultant BL-23-O-glucoside (BL-23-O-Glc) can be malonylated, but the physiological significance of and enzyme required for this reaction had remained unknown. Here, we show that in Arabidopsis thaliana malonylation of BL-23-O-Glc is catalyzed by the acyltransferase phenolic glucoside malonyl-transferase 1 (PMAT1), which is also known to malonylate phenolic glucosides and lipid amides. Loss of PMAT1 abolished BL-23-O-malonylglucoside formation and enriched BL-23-O-Glc, showing that the enzyme acts on the glucoside. An overexpression of PMAT1 in plants where UGT73C6 was also overexpressed, and thus, BL-23-O-Glc formation was promoted, enhanced the symptoms of BR-deficiency of UGT73C6oe plants, providing evidence that PMAT1 contributes to BL inactivation. Based on these results, a model is proposed in which PMAT1 acts in the conversion of both endogenous and xenobiotic glucosides to adjust metabolic homeostasis in spatial and temporal modes.
Topics: Acyltransferases; Arabidopsis; Arabidopsis Proteins; Brassinosteroids; Gene Expression Regulation, Plant; Glucosides; Glycosyltransferases; Plants, Genetically Modified; Steroids; Steroids, Heterocyclic; Transferases
PubMed: 33600798
DOI: 10.1016/j.jbc.2021.100424 -
Journal of Translational Medicine Nov 2023Protein palmitoylation, which is catalyzed by palmitoyl-transferase and de-palmitoyl-transferase, plays a crucial role in various biological processes. However, the...
BACKGROUND
Protein palmitoylation, which is catalyzed by palmitoyl-transferase and de-palmitoyl-transferase, plays a crucial role in various biological processes. However, the landscape and dynamics of protein palmitoylation in human cancers are not well understood.
METHODS
We utilized 23 palmitoyl-acyltransferases and seven de-palmitoyl-acyltransferases as palmitoylation-related genes for protein palmitoylation analysis. Multiple publicly available datasets were employed to conduct pan-cancer analysis, examining the transcriptome, genomic alterations, clinical outcomes, and correlation with c-Myc (Myc) for palmitoylation-related genes. Real-time quantitative PCR and immunoblotting were performed to assess the expression of palmitoylation-related genes and global protein palmitoylation levels in cancer cells treated with Myc depletion or small molecule inhibitors. Protein docking and drug sensitivity analyses were employed to predict small molecules that target palmitoylation-related genes.
RESULTS
We identified associations between palmitoylation and cancer subtype, stage, and patient survival. We discovered that abnormal DNA methylation and oncogenic Myc-driven transcriptional regulation synergistically contribute to the dysregulation of palmitoylation-related genes. This dysregulation of palmitoylation was closely correlated with immune infiltration in the tumor microenvironment and the response to immunotherapy. Importantly, dysregulated palmitoylation was found to modulate canonical cancer-related pathways, thus influencing tumorigenesis. To support our findings, we performed a proof-of-concept experiment showing that depletion of Myc led to reduced expression of most palmitoylation-related genes, resulting in decreased global protein palmitoylation levels. Through mass spectrometry and enrichment analyses, we also identified palmitoyl-acyltransferases ZDHHC7 and ZDHHC23 as significant contributors to mTOR signaling, DNA repair, and immune pathways, highlighting their potential roles in tumorigenesis. Additionally, our study explored the potential of three small molecular (BI-2531, etoposide, and piperlongumine) to modulate palmitoylation by targeting the expression or activity of palmitoylation-related genes or enzymes.
CONCLUSIONS
Overall, our findings underscore the critical role of dysregulated palmitoylation in tumorigenesis and the response to immunotherapy, mediated through classical cancer-related pathways and immune cell infiltration. Additionally, we propose that the aforementioned three small molecule hold promise as potential therapeutics for modulating palmitoylation, thereby offering novel avenues for cancer therapy.
Topics: Humans; Lipoylation; Acyltransferases; Carcinogenesis; Neoplasms; Cell Transformation, Neoplastic; Tumor Microenvironment
PubMed: 37978524
DOI: 10.1186/s12967-023-04611-8 -
Nature Chemical Biology Mar 2023Ferroptosis is an iron-dependent form of cell death driven by oxidation of polyunsaturated fatty acid (PUFA) phospholipids. Large-scale genetic screens have uncovered a...
Ferroptosis is an iron-dependent form of cell death driven by oxidation of polyunsaturated fatty acid (PUFA) phospholipids. Large-scale genetic screens have uncovered a specialized role for PUFA ether phospholipids (ePLs) in promoting ferroptosis. Understanding of the enzymes involved in PUFA-ePL production, however, remains incomplete. Here we show, using a combination of pathway mining of genetic dependency maps, AlphaFold-guided structure predictions and targeted lipidomics, that the uncharacterized transmembrane protein TMEM164-the genetic ablation of which has been shown to protect cells from ferroptosis-is a cysteine active center enzyme that selectively transfers C20:4 acyl chains from phosphatidylcholine to lyso-ePLs to produce PUFA ePLs. Genetic deletion of TMEM164 across a set of ferroptosis-sensitive cancer cell lines caused selective reductions in C20:4 ePLs with minimal effects on C20:4 diacyl PLs, and this lipid profile produced a variable range of protection from ferroptosis, supportive of an important but contextualized role for C20:4 ePLs in this form of cell death.
Topics: Acyltransferases; Phospholipid Ethers; Phospholipids; Phosphatidylcholines; Oxidation-Reduction
PubMed: 36782012
DOI: 10.1038/s41589-022-01253-7 -
Molecular Cell Dec 2021The Sonic Hedgehog (SHH) morphogen pathway is fundamental for embryonic development and stem cell maintenance and is implicated in various cancers. A key step in...
The Sonic Hedgehog (SHH) morphogen pathway is fundamental for embryonic development and stem cell maintenance and is implicated in various cancers. A key step in signaling is transfer of a palmitate group to the SHH N terminus, catalyzed by the multi-pass transmembrane enzyme Hedgehog acyltransferase (HHAT). We present the high-resolution cryo-EM structure of HHAT bound to substrate analog palmityl-coenzyme A and a SHH-mimetic megabody, revealing a heme group bound to HHAT that is essential for HHAT function. A structure of HHAT bound to potent small-molecule inhibitor IMP-1575 revealed conformational changes in the active site that occlude substrate binding. Our multidisciplinary analysis provides a detailed view of the mechanism by which HHAT adapts the membrane environment to transfer an acyl chain across the endoplasmic reticulum membrane. This structure of a membrane-bound O-acyltransferase (MBOAT) superfamily member provides a blueprint for other protein-substrate MBOATs and a template for future drug discovery.
Topics: Acylation; Acyltransferases; Allosteric Regulation; Animals; COS Cells; Catalytic Domain; Chlorocebus aethiops; Cryoelectron Microscopy; Enzyme Inhibitors; HEK293 Cells; Hedgehog Proteins; Heme; Humans; Membrane Proteins; Molecular Dynamics Simulation; Palmitoyl Coenzyme A; Protein Conformation; Signal Transduction; Structure-Activity Relationship
PubMed: 34890564
DOI: 10.1016/j.molcel.2021.11.018 -
Journal of the American Chemical Society Apr 2022Chronically elevated circulating fatty acid levels promote lipid accumulation in nonadipose tissues and cause lipotoxicity. Adipose triglyceride lipase (ATGL) critically...
Chronically elevated circulating fatty acid levels promote lipid accumulation in nonadipose tissues and cause lipotoxicity. Adipose triglyceride lipase (ATGL) critically determines the release of fatty acids from white adipose tissue, and accumulating evidence suggests that inactivation of ATGL has beneficial effects on lipotoxicity-driven disorders including insulin resistance, steatohepatitis, and heart disease, classifying ATGL as a promising drug target. Here, we report on the development and biological characterization of the first small-molecule inhibitor of human ATGL. This inhibitor, designated NG-497, selectively inactivates human and nonhuman primate ATGL but not structurally and functionally related lipid hydrolases. We demonstrate that NG-497 abolishes lipolysis in human adipocytes in a dose-dependent and reversible manner. The combined analysis of mouse- and human-selective inhibitors, chimeric ATGL proteins, and homology models revealed detailed insights into enzyme-inhibitor interactions. NG-497 binds ATGL within a hydrophobic cavity near the active site. Therein, three amino acid residues determine inhibitor efficacy and species selectivity and thus provide the molecular scaffold for selective inhibition.
Topics: Acyltransferases; Adipocytes; Animals; Fatty Acids; Humans; Lipolysis; Mice
PubMed: 35362954
DOI: 10.1021/jacs.1c10836 -
Molecular Metabolism Sep 2022Mutations in the copper-zinc superoxide dismutase (SOD1) gene cause familial amyotrophic lateral sclerosis (ALS), a progressive fatal neuromuscular disease characterized...
OBJECTIVE
Mutations in the copper-zinc superoxide dismutase (SOD1) gene cause familial amyotrophic lateral sclerosis (ALS), a progressive fatal neuromuscular disease characterized by motor neurons death and severe skeletal muscle degeneration. However, there is no effective treatment for this debilitating disease, since the underlying cause for the pathogenesis remains poorly understood. Here, we investigated a role of acyl-CoA:lysocardiolipin acyltransferase 1 (ALCAT1), an acyltransferase that promotes mitochondrial dysfunction in age-related diseases by catalyzing pathological remodeling of cardiolipin, in promoting the development of ALS in the SOD1 transgenic mice.
METHODS
Using SOD1 transgenic mice with targeted deletion of the ALCAT1 gene and treated with Dafaglitapin (Dafa), a very potent and highly selective ALCAT1 inhibitor, we determined whether ablation or pharmaceutical inhibition of ALCAT1 by Dafa would mitigate ALS and the underlying pathogenesis by preventing pathological remodeling of cardiolipin, oxidative stress, and mitochondrial dysfunction by multiple approaches, including lifespan analysis, behavioral tests, morphological and functional analysis of skeletal muscle, electron microscopic and Seahorse analysis of mitochondrial morphology and respiration, western blot analysis of the SOD1 protein aggregation, and lipidomic analysis of cardiolipin content and acyl composition in mice spinal cord.
RESULTS
ALCAT1 protein expression is potently upregulated in the skeletal muscle of the SOD1 mice. Consequently, ablation or pharmacological inhibition of ALCAT1 by Dafa attenuates motor neuron dysfunction, neuronal inflammation, and skeletal muscle atrophy in SOD1 mice by preventing SOD1 protein aggregation, mitochondrial dysfunction, and pathological CL remodeling, leading to moderate extension of lifespan in the SOD1 transgenic mice.
CONCLUSIONS
ALCAT1 promotes the development of ALS by linking SOD1 protein aggregation to mitochondrial dysfunction, implicating Dafa as a potential treatment for this debilitating disorder.
Topics: Acyltransferases; Amyotrophic Lateral Sclerosis; Animals; Cardiolipins; Disease Models, Animal; Mice; Mice, Transgenic; Protein Aggregates; Superoxide Dismutase; Superoxide Dismutase-1
PubMed: 35772643
DOI: 10.1016/j.molmet.2022.101536 -
PLoS Pathogens May 2023The severity of disease following infection with SARS-CoV-2 is determined by viral replication kinetics and host immunity, with early T cell responses and/or suppression...
The severity of disease following infection with SARS-CoV-2 is determined by viral replication kinetics and host immunity, with early T cell responses and/or suppression of viraemia driving a favourable outcome. Recent studies uncovered a role for cholesterol metabolism in the SARS-CoV-2 life cycle and in T cell function. Here we show that blockade of the enzyme Acyl-CoA:cholesterol acyltransferase (ACAT) with Avasimibe inhibits SARS-CoV-2 pseudoparticle infection and disrupts the association of ACE2 and GM1 lipid rafts on the cell membrane, perturbing viral attachment. Imaging SARS-CoV-2 RNAs at the single cell level using a viral replicon model identifies the capacity of Avasimibe to limit the establishment of replication complexes required for RNA replication. Genetic studies to transiently silence or overexpress ACAT isoforms confirmed a role for ACAT in SARS-CoV-2 infection. Furthermore, Avasimibe boosts the expansion of functional SARS-CoV-2-specific T cells from the blood of patients sampled during the acute phase of infection. Thus, re-purposing of ACAT inhibitors provides a compelling therapeutic strategy for the treatment of COVID-19 to achieve both antiviral and immunomodulatory effects. Trial registration: NCT04318314.
Topics: Humans; Acyltransferases; Antiviral Agents; COVID-19; SARS-CoV-2; T-Lymphocytes
PubMed: 37134108
DOI: 10.1371/journal.ppat.1011323 -
Trends in Endocrinology and Metabolism:... Feb 2020Ghrelin and the growth hormone secretagogue receptor 1a (GHS-R1a) are important targets for disorders related to energy balance and metabolic regulation. Pharmacological... (Review)
Review
Ghrelin and the growth hormone secretagogue receptor 1a (GHS-R1a) are important targets for disorders related to energy balance and metabolic regulation. Pharmacological control of ghrelin signaling is a promising avenue to address health issues involving appetite, weight gain, obesity, and related metabolic disorders, and may be an option for patients suffering from wasting conditions like cachexia. In this review, we summarize recent developments in the biochemistry of ghrelin and GHS-R1a signaling. These include unravelling the enzymatic transformations that generate active ghrelin and the discovery of multiple proteins that interact with ghrelin and GHS-R1a to regulate signaling. Furthermore, we propose that harnessing these processes will lead to highly selective treatments to address obesity, diabetes, and other metabolism-linked disorders.
Topics: Acyltransferases; Animals; Antimicrobial Cationic Peptides; Blood Proteins; Diabetes Mellitus; Ghrelin; Humans; Obesity; Receptors, Ghrelin; Signal Transduction
PubMed: 31636018
DOI: 10.1016/j.tem.2019.09.006 -
The Journal of Biological Chemistry Jan 2022The diversity of glycerophospholipid species in cellular membranes is immense and affects various biological functions. Glycerol-3-phosphate acyltransferases (GPATs) and... (Review)
Review
The diversity of glycerophospholipid species in cellular membranes is immense and affects various biological functions. Glycerol-3-phosphate acyltransferases (GPATs) and lysophospholipid acyltransferases (LPLATs), in concert with phospholipase As enzymes, contribute to this diversity via selective esterification of fatty acyl chains at the sn-1 or sn-2 positions of membrane phospholipids. These enzymes are conserved across all kingdoms, and in mammals four GPATs of the 1-acylglycerol-3-phosphate O-acyltransferase (AGPAT) family and at least 14 LPLATs, either of the AGPAT or the membrane-bound O-acyltransferase (MBOAT) families, have been identified. Here we provide an overview of the biochemical and biological activities of these mammalian enzymes, including their predicted structures, involvements in human diseases, and essential physiological roles as revealed by gene-deficient mice. Recently, the nomenclature used to refer to these enzymes has generated some confusion due to the use of multiple names to refer to the same enzyme and instances of the same name being used to refer to completely different enzymes. Thus, this review proposes a more uniform LPLAT enzyme nomenclature, as well as providing an update of recent advances made in the study of LPLATs, continuing from our JBC mini review in 2009.
Topics: 1-Acylglycerophosphocholine O-Acyltransferase; Animals; Glycerophospholipids; Humans; Lysophospholipids; Terminology as Topic
PubMed: 34890643
DOI: 10.1016/j.jbc.2021.101470