Strategic lead compound design and development utilizing computer-aided drug discovery (CADD) to address herbicide-resistant Phalaris minor in wheat fields.

Wheat (Triticum aestivum) is a vital cereal crop and a staple food source worldwide. However, wheat grain productivity has significantly declined as a consequence of infestations by Phalaris minor. Traditional weed control methods have proven inadequate owing to the physiological similarities between P. minor and wheat during early growth stages. Consequently, farmers have turned to herbicides, targeting acetyl-CoA carboxylase (ACCase), acetolactate synthase (ALS) and photosystem II (PSII). Isoproturon targeting PSII was introduced in mid-1970s, to manage P. minor infestations. Despite their effectiveness, the repetitive use of these herbicides has led to the development of herbicide-resistant P. minor biotypes, posing a significant challenge to wheat productivity. To address this issue, there is a pressing need for innovative weed management strategies and the discovery of novel herbicide molecules. The integration of computer-aided drug discovery (CADD) techniques has emerged as a promising approach in herbicide research, that facilitates the identification of herbicide targets and enables the screening of large chemical libraries for potential herbicide-like molecules. By employing techniques such as homology modelling, molecular docking, molecular dynamics simulation and pharmacophore modelling, CADD has become a rapid and cost-effective medium to accelerate the herbicide discovery process significantly. This approach not only reduces the dependency on traditional experimental methods, but also enhances the precision and efficacy of herbicide development. This article underscores the critical role of bioinformatics and CADD in developing next-generation herbicides, offering new hope for sustainable weed management and improved wheat cultivation practices. © 2024 Society of Chemical Industry.

Genomic and biochemical analysis of lipid biosynthesis in Cyanophora paradoxa: Limited role of chloroplast in fatty acid synthesis.

Archaeplastida, a group of photosynthetic organisms with primary plastids, consists of green algae (plus plants), red algae, and glaucophytes. In contrast to green and red algae, information on lipids and lipid biosynthesis still needs to be included in the glaucophytes. The chloroplast is the site of photosynthesis and fatty acid synthesis in all photosynthetic organisms known to date. However, the genomic data of the glaucophyte Cyanophora paradoxa suggested the lack of acetyl CoA carboxylase and most components of fatty acid synthase in the chloroplast. Instead, multifunctional fatty acid synthase and acetyl CoA carboxylase are likely to reside in the cytosol. To examine this hypothesis, we measured fatty acid synthesis in isolated chloroplasts and whole cells using stable isotope labeling. The chloroplasts had very low activity of fatty acid synthesis, if any. Most processes of fatty acid synthesis, including elongation and desaturation, must be performed within the cytosol, and the fatty acids imported into the chloroplasts are assembled into the chloroplast lipids by the enzymes common to other algae and plants. Cyanophora paradoxa is a rare organism in which fatty acid synthesis and photosynthesis are not tightly linked. This could question the common origin of these two biosynthetic processes in Archaeplastida.

Investigation of acetyl-CoA carboxylase-inhibiting herbicides that exhibit soybean crop selectivity.

The sustainable control of weed populations, particularly resistant species, is a significant challenge in agriculture around the world. The α-aryl-keto-enol (aryl-KTE) class of acetyl-CoA carboxylase (ACCase)-inhibiting herbicides represent a possible solution for the control of resistant grasses even though achieving crop selectivity remains a challenge. Herein, we present some of our investigations into identifying the most promising structural features within the aryl-KTE class that give the highest chance of achieving soybean crop selectivity, whilst also maintaining strong and broad efficacy against problematic weed species. We further examined our results by preparing new aryl-KTE molecules which were evaluated in glasshouse screening assays for their herbicidal efficacy as well as their soybean selectivity. We consider that uniting this approach with other optimization criteria, such as toxicological and environmental safety profiles, will enable the streamlining of crop protection optimizations programmes, ultimately delivering safer and more sustainable solutions to farmers and consumers. © 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Augmented Global Protein Acetylation Diminishes Cell Growth and Migration of Cholangiocarcinoma Cells.

We have previously shown that the overexpression of acetyl-CoA carboxylase 1 (ACC1) was associated with the poor prognosis of cholangiocarcinoma (CCA) patients, and suppression of its expression in CCA cell lines deteriorated cell growth. The present study explored the mechanism by which ACC1 inhibition affects global protein acetylation, using genetic knockdown and pharmacological inhibition with an ACC1 inhibitor ND-646 as models. Both ACC1 knockdown and ACC1-inhibitor-treated cells displayed the hyperacetylation of proteins, accompanied by impaired growth and migration. The immunoprecipitation of hyperacetylated proteins using the anti-acetylated lysine antibody, followed by tandem mass spectrometry, identified three potential verification candidates, namely POTE ankyrin domain family member E, peroxisomal biogenesis factor 1, and heat shock protein 90 beta (HSP90B). HSP90 acetylation was the candidate selected for the verification of protein acetylation. To establish the effects of protein hyperacetylation, treatment with suberoylanilide hydroxamic acid (SAHA), a lysine deacetylase inhibitor, was conducted, and this served as an independent model. Decreased tumor growth but increased acetylated protein levels were observed in ACC1-KD xenograft tumors. Hyperacetylated-alleviated cell growth and migration were consistently observed in the SAHA-treated models. The molecular linkage between protein hyperacetylation and the AKT/GSK3ß/Snail pathway was demonstrated. This study highlighted the importance of protein acetylation in CCA progression, suggesting that ACC1 and KDAC are potential targets for CCA treatment.

Nonalcoholic Fatty Liver Disease and Staging of Hepatic Fibrosis.

Nonalcoholic fatty liver disease (NAFLD) is in parallel with the obesity epidemic, and it is the most common cause of liver diseases. The patients with severe insulin-resistant diabetes having high body mass index (BMI), high-grade adipose tissue insulin resistance, and high hepatocellular triacylglycerols (triglycerides; TAG) content develop hepatic fibrosis within a 5-year follow-up. Insulin resistance with the deficiency of insulin receptor substrate-2 (IRS-2)-associated phosphatidylinositol 3-kinase (PI3K) activity causes an increase in intracellular fatty acid-derived metabolites such as diacylglycerol (DAG), fatty acyl CoA, or ceramides. Lipotoxicity-related mechanism of NAFLD could be explained still best by the "double-hit" hypothesis. Insulin resistance is the major mechanism in the development and progression of NAFLD/nonalcoholic steatohepatitis (NASH). Metabolic oxidative stress, autophagy, and inflammation induce NASH progression. In the "first hit" the hepatic concentrations of diacylglycerol increase with an increase in saturated liver fat content in human NAFLD. Activities of mitochondrial respiratory chain complexes are decreased in the liver tissue of patients with NASH. Hepatocyte lipoapoptosis is a critical feature of NASH. In the "second hit," reduced glutathione levels due to oxidative stress lead to the overactivation of c-Jun N-terminal kinase (JNK)/c-Jun signaling that induces cell death in the steatotic liver. Accumulation of toxic levels of reactive oxygen species (ROS) is caused at least by two ineffectual cyclical pathways. First is the endoplasmic reticulum (ER) oxidoreductin (Ero1)-protein disulfide isomerase oxidation cycle through the downstream of the inner membrane mitochondrial oxidative metabolism and the second is the Kelch like-ECH-associated protein 1 (Keap1)-nuclear factor (erythroid-derived 2)-like 2 (Nrf2) pathways. In clinical practice, on ultrasonographic examination, the elevation of transaminases, γ-glutamyltransferase, and the aspartate transaminase to platelet ratio index indicates NAFLD. Fibrosis-4 index, NAFLD fibrosis score, and cytokeratin18 are used for grading steatosis, staging fibrosis, and discriminating the NASH from simple steatosis, respectively. In addition to ultrasonography, "controlled attenuation parameter," "magnetic resonance imaging proton-density fat fraction," "ultrasound-based elastography," "magnetic resonance elastography," "acoustic radiation force impulse elastography imaging," "two-dimensional shear-wave elastography with supersonic imagine," and "vibration-controlled transient elastography" are recommended as combined tests with serum markers in the clinical evaluation of NAFLD. However, to confirm the diagnosis of NAFLD, a liver biopsy is the gold standard. Insulin resistance-associated hyperinsulinemia directly accelerates fibrogenesis during NAFLD development. Although hepatocyte lipoapoptosis is a key driving force of fibrosis progression, hepatic stellate cells and extracellular matrix cells are major fibrogenic effectors. Thereby, these are pharmacological targets of therapies in developing hepatic fibrosis. Nonpharmacological management of NAFLD mainly consists of two alternatives: lifestyle modification and metabolic surgery. Many pharmacological agents that are thought to be effective in the treatment of NAFLD have been tried, but due to lack of ability to attenuate NAFLD, or adverse effects during the phase trials, the vast majority could not be licensed.

Metproxybicyclone, a Novel Carbocyclic Aryl-dione Acetyl-CoA Carboxylase-Inhibiting Herbicide for the Management of Sensitive and Resistant Grass Weeds.

Postemergence control of grass weeds has become problematic due to the evolution of resistance to 5-enolpyruvylshikimate-3-phosphate synthase, acetyl-CoA carboxylase (ACCase), and acetolactate synthase-inhibiting herbicides. Herein we describe the invention and synthesis journey toward metproxybicyclone, the first commercial carbocyclic aryl-dione ACCase-inhibiting herbicide for the cost-effective management of grass weeds in dicotyledonous crops and in preplant burndown applications. Glasshouse and field experiments have shown that metproxybicyclone is safe for use on soybean, cotton, and sugar beet, among other crops. It is effective on a variety of key grass weeds including Eleusine indica, Digitaria insularis, Sorghum halepense, and Echinochloa crus-galli. Importantly, metproxybicyclone was more efficacious at killing resistant grass weed populations than current ACCase herbicides. Metproxybicyclone controlled the main ACCase target-site and nontarget site resistant mechanisms in characterized Lolium multiflorum and E. indica populations under glasshouse conditions. Excellent control of a broad resistance-causing D2078G target-site mutant E. indica population was also observed under field conditions.

Bioinformatics Identification and Expression Analysis of Acetyl-CoA Carboxylase Reveal Its Role in Isoflavone Accumulation during Soybean Seed Development.

Isoflavones belong to the class of flavonoid compounds, which are important secondary metabolites that play a crucial role in plant development and defense. Acetyl-CoA carboxylase (ACCase) is a biotin-dependent enzyme that catalyzes the conversion of Acetyl-CoA into Malonyl-CoA in plants. It is a key enzyme in fatty acid synthesis and also catalyzes the production of various secondary metabolites. However, information on the ACC gene family in the soybean (Glycine max L. Merr.) genome and the specific members involved in isoflavone biosynthesis is still lacking. In this study, we identified 20 ACC family genes (GmACCs) from the soybean genome and further characterized their evolutionary relationships and expression patterns. Phylogenetic analysis showed that the GmACCs could be divided into five groups, and the gene structures within the same groups were highly conserved, indicating that they had similar functions. The GmACCs were randomly distributed across 12 chromosomes, and collinearity analysis suggested that many GmACCs originated from tandem and segmental duplications, with these genes being under purifying selection. In addition, gene expression pattern analysis indicated that there was functional divergence among GmACCs in different tissues. The GmACCs reached their peak expression levels during the early or middle stages of seed development. Based on the transcriptome and isoflavone content data, a weighted gene co-expression network was constructed, and three candidate genes (Glyma.06G105900, Glyma.13G363500, and Glyma.13G057400) that may positively regulate isoflavone content were identified. These results provide valuable information for the further functional characterization and application of GmACCs in isoflavone biosynthesis in soybean.

Evolution of the regulatory subunits for the heteromeric acetyl-CoA carboxylase.

The committed step for de novo fatty acid (FA) synthesis is the ATP-dependent carboxylation of acetyl-coenzyme A catalysed by acetyl-CoA carboxylase (ACCase). In most plants, ACCase is a multi-subunit complex orthologous to prokaryotes. However, unlike prokaryotes, the plant and algal orthologues are comprised both catalytic and additional dedicated regulatory subunits. Novel regulatory subunits, biotin lipoyl attachment domain-containing proteins (BADC) and carboxyltransferase interactors (CTI) (both three-gene families in Arabidopsis) represent new effectors specific to plants and certain algal species. The evolutionary history of these genes in autotrophic eukaryotes remains elusive, making it an ongoing area of research. Analyses of potential protein-protein and co-occurrence interactions, informed by gene network patterns using the STRING database, in Arabidopsis thaliana and Chlamydomonas reinhardtii unveil intricate gene associations with ACCase, suggesting a complex interplay between FA synthesis and other cellular processes. Among both species, a higher number of co-expressed genes was identified in Arabidopsis, indicating a wider potential regulatory network of ACCase in plants. This review investigates the extent to which these genes arose in autotrophic eukaryotes and provides insights into their evolutionary trajectory. This article is part of the theme issue 'The evolution of plant metabolism'.

Fortunefuroic Acid J from Keteleeria Hainanensis and its Dual Inhibitory Effects on ATP-Citrate Lyase and Acetyl-CoA Carboxylase.

A previously undescribed triterpenoid (fortunefuroic acid J, 1) was isolated from the endangered conifer Keteleeria hainanensis, along with 20 other known terpenoids. Compound 1 is characterized by an unusual 3,4-seco-9ßH-lanost-3-oic acid motif, featuring a rare furoic acid moiety in its lateral chain. The structure elucidation of this compound was achieved through a combination of spectroscopic and computational methods. The C-15 epimers of 15-methoxypinusolidic acid (15R-8 and 15S-9) were successfully separated and identified for the first time. Compound 1 demonstrated dual inhibitory effects against ATP-citrate lyase (ACL, IC50: 0.92 µM) and acetyl-CoA carboxylase 1 (ACC1, IC50: 10.76 µM). Compounds 2 and 11 exclusively inhibited ACL, exhibiting IC50 values of 2.64 and 6.35 µM, respectively. Compound 1 is classified among the fortunefuroic acid-type compounds, previously isolated from K. fortunei, distinguished by the presence of a rare furoic acid moiety in their lateral chain. The chemotaxonomic significance of the 9ßH-lanost-26-oic acids in Keteleeria was briefly discussed. These findings highlight the importance of conserving plant species diversity, thereby enhancing the exploration of structurally diverse compounds and potential avenues for developing new therapeutics targeting ACL/ACC1-associated diseases.

Acetyl-CoA Carboxylase Proteolysis-Targeting Chimeras: Conceptual Design and Application as Insecticides.

Novel approaches for pest control are essential to ensure a sufficient food supply for the growing global population. The development of new insecticides must meet rigorous regulatory requirements for safety and address the resistance issues of existing insecticides. Proteolysis-targeting chimeras (PROTACs), originally developed for human diseases, show promise in agriculture. They offer innovative insecticides tailored to overcome resistance, opening avenues for agricultural applications. In this study, we developed small-molecule degraders by incorporating pomalidomide as an E3 ligand. These degraders were linked to a ligand (spirotetratmat enol) targeting the ACC protein through a flexible chain, aiming to achieve the efficient control of insects. Compounds 9a-9d were designed, synthesized, and evaluated for biological activities and mechanisms. Among them, 9b exhibited superior potency against Aphis craccivora (LC50 = 107.8 µg mL-1) compared to others and effectively degraded ACC proteins through the ubiquitin-proteasome system. These findings highlight the potential of utilizing PROTAC-based approaches in the development of insecticides for efficient pest control.

Enhancing Maturation and Translatability of Human Pluripotent Stem Cell-Derived Cardiomyocytes through a Novel Medium Containing Acetyl-CoA Carboxylase 2 Inhibitor.

Human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) constitute an appealing tool for drug discovery, disease modeling, and cardiotoxicity screening. However, their physiological immaturity, resembling CMs in the late fetal stage, limits their utility. Herein, we have developed a novel, scalable cell culture medium designed to enhance the maturation of hPSC-CMs. This medium facilitates a metabolic shift towards fatty acid utilization and augments mitochondrial function by targeting Acetyl-CoA carboxylase 2 (ACC2) with a specific small molecule inhibitor. Our findings demonstrate that this maturation protocol significantly advances the metabolic, structural, molecular and functional maturity of hPSC-CMs at various stages of differentiation. Furthermore, it enables the creation of cardiac microtissues with superior structural integrity and contractile properties. Notably, hPSC-CMs cultured in this optimized maturation medium display increased accuracy in modeling a hypertrophic cardiac phenotype following acute endothelin-1 induction and show a strong correlation between in vitro and in vivo target engagement in drug screening efforts. This approach holds promise for improving the utility and translatability of hPSC-CMs in cardiac disease modeling and drug discovery.

SomaLogic proteomics reveals new biomarkers and provides mechanistic, clinical insights into Acetyl coA Carboxylase (ACC) inhibition in Non-alcoholic Steatohepatitis (NASH).

Non-alcoholic Fatty Liver Disease (NAFLD) and Non-alcoholic Steatohepatitis (NASH) are major metabolic diseases with increasing global prevalence and no approved therapies. There is a mounting need to develop biomarkers of diagnosis, prognosis and treatment response that can effectively replace current requirements for liver biopsies, which are invasive, error-prone and expensive. We performed SomaLogic serum proteome profiling with baseline (n = 231) and on-treatment (n = 72, Weeks 12 and 16, Placebo and 25 mg PF-05221304) samples from a Phase 2a trial (NCT03248882) with Clesacostat (PF-05221304), an acetyl coA carboxylase inhibitor (ACCi) in patients with NAFLD/NASH. SomaSignal NASH probability scores and expression data for 7000+ analytes were analyzed to identify potential biomarkers associated with baseline clinical measures of NAFLD/NASH [Magnetic Resonance Imaging-Proton Density Fat Fraction (MRI-PDFF), alanine aminotransferase (ALT) and aspartate aminotransferase (AST)] as well as biomarkers of treatment response to ACCi. SomaSignal NASH probability scores identified biopsy-proven/clinically defined NIT-based (Presumed) NASH classification of the cohort with > 70% agreement. Clesacostat-induced reduction in steatosis probability scores aligned with observed clinical reduction in hepatic steatosis based on MRI-PDFF. We identify a set of 69 analytes that robustly correlate with clinical measures of hepatic inflammation and steatosis (MRI-PDFF, ALT and AST), 27 of which were significantly reversed with ACC inhibition. Clesacostat treatment dramatically upregulated Wnt5a protein and Apolipoproteins C3 and E, with drug-induced changes significantly correlating to changes on MRI-PDFF. Our data demonstrate the utility of SomaLogic- analyte panel for diagnosis and treatment response in NAFLD/NASH and provide potential new mechanistic insights into liver steatosis reduction, inflammation and serum triglyceride elevation with ACC inhibition. (Clinical Trial Identifier: NCT03248882).

Deciphering structural variation upon biotinylation of biotin carboxyl carrier protein domain in Streptococcus pneumoniae.

Streptococcus pneumoniae is a leading cause of community-acquired pneumonia and is responsible for acute invasive and non-invasive infections. Fight against pneumococcus is currently hampered by insufficient vaccine coverage and rising antimicrobial resistance, making the research necessary on novel drug targets. High-throughput mutagenesis has shown that acetyl-CoA carboxylase (ACC) is an essential enzyme in S. pneumoniae which converts acetyl-CoA to malonyl-CoA, a key step in fatty acid biosynthesis. ACC has four subunits; Biotin carboxyl carrier protein (BCCP), Biotin carboxylase (BC), Carboxyl transferase subunit α and ß. Biotinylation of S. pneumoniae BCCP (SpBCCP) is required for the activation of ACC complex. In this study, we have biophysically characterized the apo- and holo- biotinylating domain SpBCCP80. We have performed 2D and 3D NMR experiments to analyze the changes in amino acid residues upon biotinylation of SpBCCP80. Further, we used NMR backbone chemical shift assignment data for bioinformatical analyses to determine the secondary and tertiary structure of proteins. We observed major changes in AMKVM motif and thumb region of SpBCCP80 upon biotinylation. Overall, this work provides structural insight into the apo- to holo- conversion of SpBCCP80 which can be further used as a drug target against S. pneumoniae.

Differential Resistance to Acetyl-CoA Carboxylase Inhibitors in Rice: Insights from Two Distinct Target-Site Mutations.

Weeds present a significant challenge to agricultural productivity, and acetyl-CoA carboxylase (ACCase)-inhibiting herbicides have proven to be effective in managing weed populations in rice fields. To develop ACCase-inhibiting herbicide-resistant rice, we generated mutants of rice ACCase (OsACC) featuring Ile-1792-Leu or Gly-2107-Ser substitutions through ethyl methyl sulfonate (EMS) mutagenesis. The Ile-1792-Leu mutant displayed cross-resistance to aryloxyphenoxypropionate (APP) and phenylpyrazoline (DEN) herbicides, whereas the Gly-2107-Ser mutants primarily exhibited cross-resistance to APP herbicides with diminished resistance to the DEN herbicide. In vitro assays of the OsACC activity revealed an increase in resistance to haloxyfop and quizalofop, ranging from 4.84- to 29-fold in the mutants compared to that in wild-type. Structural modeling revealed that both mutations likely reduce the binding affinity between OsACC and ACCase inhibitors, thereby imparting resistance. This study offers insights into two target-site mutations, contributing to the breeding of herbicide-resistant rice and presenting alternative weed management strategies in rice cultivation.

Loss of YhcB results in overactive fatty acid biosynthesis.

Loss of the Escherichia coli inner membrane protein YhcB results in pleomorphic cell morphology and clear growth defects. Prior work suggested that YhcB was directly involved in cell division or peptidoglycan assembly. We found that loss of YhcB is detrimental in genetic backgrounds in which lipopolysaccharide (LPS) or glycerophospholipid (GPL) synthesis is altered. The growth defect of ΔyhcB could be rescued through inactivation of the Mla pathway, a system responsible for the retrograde transport of GPLs that are mislocalized to the outer leaflet of the outer membrane. Interestingly, this rescue was dependent upon the outer membrane phospholipase PldA that cleaves GPLs at the bacterial surface. Since the freed fatty acids resulting from PldA activity serve as a signal to the cell to increase LPS synthesis, this result suggested that outer membrane lipids are imbalanced in ΔyhcB. Mutations that arose in ΔyhcB populations during two independent suppressor screens were in genes encoding subunits of the acetyl coenzyme A carboxylase complex, which initiates fatty acid biosynthesis (FAB). These mutations fully restored cell morphology and reduced GPL levels, which were increased compared to wild-type bacteria. Growth of ΔyhcB with the FAB-targeting antibiotic cerulenin also increased cellular fitness. Furthermore, genetic manipulation of FAB and lipid biosynthesis showed that decreasing FAB rescued ΔyhcB filamentation, whereas increasing LPS alone could not. Altogether, these results suggest that YhcB may play a pivotal role in regulating FAB and, in turn, impact cell envelope assembly and cell division.IMPORTANCESynthesis of the Gram-negative cell envelope is a dynamic and complex process that entails careful coordination of many biosynthetic pathways. The inner and outer membranes are composed of molecules that are energy intensive to synthesize, and, accordingly, these synthetic pathways are under tight regulation. The robust nature of the Gram-negative outer membrane renders it naturally impermeable to many antibiotics and therefore a target of interest for antimicrobial design. Our data indicate that when the inner membrane protein YhcB is absent in Escherichia coli, the pathway for generating fatty acid substrates needed for all membrane lipid synthesis is dysregulated which leads to increased membrane material. These findings suggest a potentially novel regulatory mechanism for controlling the rate of fatty acid biosynthesis.

Reciprocal regulation of cardiac ß-oxidation and pyruvate dehydrogenase by insulin.

The heart alters the rate and relative oxidation of fatty acids and glucose based on availability and energetic demand. Insulin plays a crucial role in this process diminishing fatty acid and increasing glucose oxidation when glucose availability increases. Loss of insulin sensitivity and metabolic flexibility can result in cardiovascular disease. It is therefore important to identify mechanisms by which insulin regulates substrate utilization in the heart. Mitochondrial pyruvate dehydrogenase (PDH) is the key regulatory site for the oxidation of glucose for ATP production. Nevertheless, the impact of insulin on PDH activity has not been fully delineated, particularly in the heart. We sought in vivo evidence that insulin stimulates cardiac PDH and that this process is driven by the inhibition of fatty acid oxidation. Mice injected with insulin exhibited dephosphorylation and activation of cardiac PDH. This was accompanied by an increase in the content of malonyl-CoA, an inhibitor of carnitine palmitoyltransferase 1 (CPT1), and, thus, mitochondrial import of fatty acids. Administration of the CPT1 inhibitor oxfenicine was sufficient to activate PDH. Malonyl-CoA is produced by acetyl-CoA carboxylase (ACC). Pharmacologic inhibition or knockout of cardiac ACC diminished insulin-dependent production of malonyl-CoA and activation of PDH. Finally, circulating insulin and cardiac glucose utilization exhibit daily rhythms reflective of nutritional status. We demonstrate that time-of-day-dependent changes in PDH activity are mediated, in part, by ACC-dependent production of malonyl-CoA. Thus, by inhibiting fatty acid oxidation, insulin reciprocally activates PDH. These studies identify potential molecular targets to promote cardiac glucose oxidation and treat heart disease.

Activation of hepatic acetyl-CoA carboxylase by S-nitrosylation in response to diet.

Nitric oxide (NO), produced primarily by nitric oxide synthase enzymes, is known to influence energy metabolism by stimulating fat uptake and oxidation. The effects of NO on de novo lipogenesis (DNL), however, are less clear. Here we demonstrate that hepatic expression of endothelial nitric oxide synthase is reduced following prolonged administration of a hypercaloric high-fat diet. This results in marked reduction in the amount of S-nitrosylation of liver proteins including notably acetyl-CoA carboxylase (ACC), the rate-limiting enzyme in DNL. We further show that ACC S-nitrosylation markedly increases enzymatic activity. Diminished endothelial nitric oxide synthase expression and ACC S-nitrosylation may thus represent a physiological adaptation to caloric excess by constraining lipogenesis. Our findings demonstrate that S-nitrosylation of liver proteins is subject to dietary control and suggest that DNL is coupled to dietary and metabolic conditions through ACC S-nitrosylation.

Revisiting liver metabolism through acetyl-CoA carboxylase inhibition.

Liver-targeted acetyl-coenzyme A (CoA) carboxylase (ACC) inhibitors in metabolic dysfunction-associated steatotic liver disease (MASLD) trials reveal notable secondary effects: hypertriglyceridemia and altered glucose metabolism, paradoxically with reduced hepatic steatosis. In their study, Deja et al. explored how hepatic ACC influences metabolism using different pharmacological and genetic methods, coupled with targeted metabolomics and stable isotope-based tracing techniques.

MiR-24-3p enhances the Treg/Th17 balance to improve cerebral ischemic injury by suppressing acetyl-CoA carboxylase 1 expression.

BACKGROUND: Targeting ACC1 (acetyl coenzyme A carboxylase 1) to restore the balance between T-helper 17 (Th17) cells and regulatory T cells (Tregs) through metabolic reprogramming has emerged as a promising strategy for reducing neuroinflammation following stroke. We examined the roles of potential miRNAs in regulating ACC1 expression in Tregs and treating ischemic stroke. METHODS: The expression of miR-24-3p in CD4+T cells of mice was confirmed. Then the protective effects of Ago-24-3p in a mouse model of prolonged occlusion of the distal middle cerebral artery (dMCAO) were examined. We analyzed the infiltration of Tregs and CD3+T cells into the brain and evaluated the improvement of neurological deficits induced by Ago-24-3p using the Modified Garcia Score and foot fault testing. RESULTS: Our investigation revealed that miR-24-3p specifically targets ACC1. Elevated levels of miR-24-3p have been demonstrated to increase the population of Tregs and enhance their proliferation and suppressive capabilities. Conversely, targeted reduction of ACC1 in CD4+T cells has been shown to counteract the improved functionality of Tregs induced by miR-24-3p. In a murine model of dMCAO, administration of Ago-24-3p resulted in a substantial reduction in the size of the infarct within the ischemic brain area. This effect was accompanied by an upregulation of Tregs and a downregulation of CD3+T cells in the ischemic brain region. In ACC1 conditional knockout mice, the ability of Ago-24-3p to enhance infiltrating Treg cells and diminish CD3+T cells in the ischemic brain area has been negated. Furthermore, its capacity to reduce infarct volume has been reversed. Furthermore, we demonstrated that Ago-24-3p sustained improvement in post-stroke neurological deficits for up to 4 weeks after the MCAO procedure. CONCLUSIONS: MiR-24-3p shows promise in the potential to reduce ACC1 expression, enhance the immunosuppressive activity of Tregs, and alleviate injuries caused by ischemic stroke. These discoveries imply that miR-24-3p could be a valuable therapeutic option for treating ischemic stroke.

Chloroflexus aurantiacus acetyl-CoA carboxylase evolves fused biotin carboxylase and biotin carboxyl carrier protein to complete carboxylation activity.

Acetyl-CoA carboxylases (ACCs) convert acetyl-CoA to malonyl-CoA, a key step in fatty acid biosynthesis and autotrophic carbon fixation pathways. Three functionally distinct components, biotin carboxylase (BC), biotin carboxyl carrier protein (BCCP), and carboxyltransferase (CT), are either separated or partially fused in different combinations, forming heteromeric ACCs. However, an ACC with fused BC-BCCP and separate CT has not been identified, leaving its catalytic mechanism unclear. Here, we identify two BC isoforms (BC1 and BC2) from Chloroflexus aurantiacus, a filamentous anoxygenic phototroph that employs 3-hydroxypropionate (3-HP) bi-cycle rather than Calvin cycle for autotrophic carbon fixation. We reveal that BC1 possesses fused BC and BCCP domains, where BCCP could be biotinylated by E. coli or C. aurantiacus BirA on Lys553 residue. Crystal structures of BC1 and BC2 at 3.2 Å and 3.0 Å resolutions, respectively, further reveal a tetramer of two BC1-BC homodimers, and a BC2 homodimer, all exhibiting similar BC architectures. The two BC1-BC homodimers are connected by an eight-stranded ß-barrel of the partially resolved BCCP domain. Disruption of ß-barrel results in dissociation of the tetramer into dimers in solution and decreased biotin carboxylase activity. Biotinylation of the BCCP domain further promotes BC1 and CTß-CTα interactions to form an enzymatically active ACC, which converts acetyl-CoA to malonyl-CoA in vitro and produces 3-HP via co-expression with a recombinant malonyl-CoA reductase in E. coli cells. This study revealed a heteromeric ACC that evolves fused BC-BCCP but separate CTα and CTß to complete ACC activity.IMPORTANCEAcetyl-CoA carboxylase (ACC) catalyzes the rate-limiting step in fatty acid biosynthesis and autotrophic carbon fixation pathways across a wide range of organisms, making them attractive targets for drug discovery against various infections and diseases. Although structural studies on homomeric ACCs, which consist of a single protein with three subunits, have revealed the "swing domain model" where the biotin carboxyl carrier protein (BCCP) domain translocates between biotin carboxylase (BC) and carboxyltransferase (CT) active sites to facilitate the reaction, our understanding of the subunit composition and catalytic mechanism in heteromeric ACCs remains limited. Here, we identify a novel ACC from an ancient anoxygenic photosynthetic bacterium Chloroflexus aurantiacus, it evolves fused BC and BCCP domain, but separate CT components to form an enzymatically active ACC, which converts acetyl-CoA to malonyl-CoA in vitro and produces 3-hydroxypropionate (3-HP) via co-expression with recombinant malonyl-CoA reductase in E. coli cells. These findings expand the diversity and molecular evolution of heteromeric ACCs and provide a structural basis for potential applications in 3-HP biosynthesis.