1
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Ansell TB, Healy M, Coupland CE, Sansom MSP, Siebold C. Mapping structural and dynamic divergence across the MBOAT family. Structure 2024; 32:1011-1022.e3. [PMID: 38636523 DOI: 10.1016/j.str.2024.03.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Revised: 02/09/2024] [Accepted: 03/22/2024] [Indexed: 04/20/2024]
Abstract
Membrane-bound O-acyltransferases (MBOATs) are membrane-embedded enzymes that catalyze acyl chain transfer to a diverse group of substrates, including lipids, small molecules, and proteins. MBOATs share a conserved structural core, despite wide-ranging functional specificity across both prokaryotes and eukaryotes. The structural basis of catalytic specificity, regulation and interactions with the surrounding environment remain uncertain. Here, we combine comparative molecular dynamics (MD) simulations with bioinformatics to assess molecular and interactional divergence across the family. In simulations, MBOATs differentially distort the bilayer depending on their substrate type. Additionally, we identify lipid binding sites surrounding reactant gates in the surrounding membrane. Complementary bioinformatic analyses reveal a conserved role for re-entrant loop-2 in MBOAT fold stabilization and a key hydrogen bond bridging DGAT1 dimerization. Finally, we predict differences in MBOAT solvation and water gating properties. These data are pertinent to the design of MBOAT-specific inhibitors that encompass dynamic information within cellular mimetic environments.
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Affiliation(s)
- T Bertie Ansell
- Department of Biochemistry, South Parks Road, Oxford OX1 3QU, UK; Division of CryoEM and Bioimaging, SSRL, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA; Department of Biology, Stanford University, Stanford, CA 94305, USA.
| | - Megan Healy
- Department of Biochemistry, South Parks Road, Oxford OX1 3QU, UK
| | - Claire E Coupland
- Division of Structural Biology, Wellcome Centre for Human Genetics, Roosevelt Drive, Oxford OX3 7BN, UK; Molecular Medicine Program, The Hospital for Sick Children, 686 Bay Street, Toronto M5G 0A4, Canada
| | - Mark S P Sansom
- Department of Biochemistry, South Parks Road, Oxford OX1 3QU, UK
| | - Christian Siebold
- Division of Structural Biology, Wellcome Centre for Human Genetics, Roosevelt Drive, Oxford OX3 7BN, UK
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2
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Millman P, Rimon RM, Toff C, Engvall M, Shaoul R, Wilschanski M, Elyashar H, Winter HS. A novel nutritional approach to infants and children with congenital diarrhea due to homozygous DGAT1 mutations. J Pediatr Gastroenterol Nutr 2024. [PMID: 38934410 DOI: 10.1002/jpn3.12241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 03/01/2024] [Accepted: 03/29/2024] [Indexed: 06/28/2024]
Abstract
OBJECTIVES Diacylglycerol acyltransferase (DGAT) catalyzes the final step in triglyceride synthesis. DGAT1 is expressed in human enterocytes and is essential for fat absorption. Homozygous DGAT1 deficiency often presents with severe diarrhea and protein-losing enteropathy (PLE) in the 1st weeks of life. Because severe restriction of fat intake controls diarrhea and decreases PLE, total parenteral nutrition (TPN) was the initial standard therapy in infants and children. We present tertiary center experience managing infants and children with DGAT1 deficiency resulting in the development of a nutritional approach that minimizes the use of TPN. METHODS From 2014 to 2020, 12 infants with DGAT1 deficiency were treated. Stool output, growth, and development, as well as essential fatty acid status, were monitored. This retrospective experience formed the basis for treatment recommendations, which include an ultralow fat formula with intermittent peripheral intravenous lipid infusions during the 1st year of life. RESULTS All patients with prolonged intestinal fat exposure had PLE, which resolved when treated with the nutrition protocol. Essential fatty acid status as measured by triene:tetraene ratios normalized in all treated patients. Over time, early genetic diagnosis and prompt initiation of an ultralow fat diet with peripheral intravenous lipid infusions replaced the need for TPN. CONCLUSIONS Children with DGAT1 deficiency respond to dietary restriction of lipids. Management with a novel nutritional approach provides effective treatment for infants with DGAT1 deficiency, treats diarrhea and PLE, promotes growth and development, avoids TPN dependency, and decreases the potential for essential fatty acid deficiency.
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Affiliation(s)
- Peri Millman
- Hadassah, Pediatric Gastroenterology, Jerusalem, Israel
| | | | - Chani Toff
- Kaplan, Pediatric Gastroenterology, Rehovot, Israel
| | - Martin Engvall
- Center for Inherited Metabolic Diseases, Karolinska University Hospital, Stockholm, Sweden
| | - Ron Shaoul
- Rambam, Pediatric Gastroenterology, Haifa, Israel
| | | | - Hila Elyashar
- Hadassah, Pediatric Gastroenterology, Jerusalem, Israel
| | - Harland S Winter
- Mass General Hospital for Children, Pediatric Gastroenterology, Boston, Massachusetts, USA
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3
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Flyckt KS, Roesler K, Haug Collet K, Jaureguy L, Booth R, Thatcher SR, Everard JD, Ripp KG, Liu ZB, Shen B, Wayne LL. A Novel Soybean Diacylglycerol Acyltransferase 1b Variant with Three Amino Acid Substitutions Increases Seed Oil Content. PLANT & CELL PHYSIOLOGY 2024; 65:872-884. [PMID: 37982755 PMCID: PMC11209548 DOI: 10.1093/pcp/pcad148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 10/24/2023] [Accepted: 11/17/2023] [Indexed: 11/21/2023]
Abstract
Improving soybean (Glycine max) seed composition by increasing the protein and oil components will add significant value to the crop and enhance environmental sustainability. Diacylglycerol acyltransferase (DGAT) catalyzes the final rate-limiting step in triacylglycerol biosynthesis and has a major impact on seed oil accumulation. We previously identified a soybean DGAT1b variant modified with 14 amino acid substitutions (GmDGAT1b-MOD) that increases total oil content by 3 percentage points when overexpressed in soybean seeds. In the present study, additional GmDGAT1b variants were generated to further increase oil with a reduced number of substitutions. Variants with one to four amino acid substitutions were screened in the model systems Saccharomyces cerevisiae and transient Nicotiana benthamiana leaf. Promising GmDGAT1b variants resulting in high oil accumulation in the model systems were selected for overexpression in soybeans. One GmDGAT1b variant with three novel amino acid substitutions (GmDGAT1b-3aa) increased total soybean oil to levels near the previously discovered GmDGAT1b-MOD variant. In a multiple location field trial, GmDGAT1b-3aa transgenic events had significantly increased oil and protein by up to 2.3 and 0.6 percentage points, respectively. The modeling of the GmDGAT1b-3aa protein structure provided insights into the potential function of the three substitutions. These findings will guide efforts to improve soybean oil content and overall seed composition by CRISPR editing.
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Affiliation(s)
- Kayla S Flyckt
- Corteva Agriscience, 7300 NW 62nd Avenue, Johnston 50131, USA
| | - Keith Roesler
- Corteva Agriscience, 7300 NW 62nd Avenue, Johnston 50131, USA
| | | | | | - Russ Booth
- Corteva Agriscience, 7300 NW 62nd Avenue, Johnston 50131, USA
| | | | - John D Everard
- Corteva Agriscience, 7300 NW 62nd Avenue, Johnston 50131, USA
| | - Kevin G Ripp
- Corteva Agriscience, 7300 NW 62nd Avenue, Johnston 50131, USA
| | - Zhan-Bin Liu
- Corteva Agriscience, 7300 NW 62nd Avenue, Johnston 50131, USA
| | - Bo Shen
- Corteva Agriscience, 7300 NW 62nd Avenue, Johnston 50131, USA
| | - Laura L Wayne
- Corteva Agriscience, 7300 NW 62nd Avenue, Johnston 50131, USA
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4
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Clews AC, Ulch BA, Jesionowska M, Hong J, Mullen RT, Xu Y. Variety of Plant Oils: Species-Specific Lipid Biosynthesis. PLANT & CELL PHYSIOLOGY 2024; 65:845-862. [PMID: 37971406 DOI: 10.1093/pcp/pcad147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 11/03/2023] [Accepted: 11/15/2023] [Indexed: 11/19/2023]
Abstract
Plant oils represent a large group of neutral lipids with important applications in food, feed and oleochemical industries. Most plants accumulate oils in the form of triacylglycerol within seeds and their surrounding tissues, which comprises three fatty acids attached to a glycerol backbone. Different plant species accumulate unique fatty acids in their oils, serving a range of applications in pharmaceuticals and oleochemicals. To enable the production of these distinctive oils, select plant species have adapted specialized oil metabolism pathways, involving differential gene co-expression networks and structurally divergent enzymes/proteins. Here, we summarize some of the recent advances in our understanding of oil biosynthesis in plants. We compare expression patterns of oil metabolism genes from representative species, including Arabidopsis thaliana, Ricinus communis (castor bean), Linum usitatissimum L. (flax) and Elaeis guineensis (oil palm) to showcase the co-expression networks of relevant genes for acyl metabolism. We also review several divergent enzymes/proteins associated with key catalytic steps of unique oil accumulation, including fatty acid desaturases, diacylglycerol acyltransferases and oleosins, highlighting their structural features and preference toward unique lipid substrates. Lastly, we briefly discuss protein interactomes and substrate channeling for oil biosynthesis and the complex regulation of these processes.
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Affiliation(s)
- Alyssa C Clews
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - Brandon A Ulch
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - Monika Jesionowska
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - Jun Hong
- Center for Desert Agriculture, King Abdullah University of Science and Technology, Thuwal 23955, Saudi Arabia
- Department of Genetics and Developmental Science, Joint International Research Laboratory of Metabolic and Developmental Sciences, State Key Laboratory of Hybrid Rice, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Robert T Mullen
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - Yang Xu
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
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5
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Xu R, Ning Y, Ren F, Gu C, Zhu Z, Pan X, Pshezhetsky AV, Ge J, Yu J. Structure and mechanism of lysosome transmembrane acetylation by HGSNAT. Nat Struct Mol Biol 2024:10.1038/s41594-024-01315-5. [PMID: 38769387 DOI: 10.1038/s41594-024-01315-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Accepted: 04/11/2024] [Indexed: 05/22/2024]
Abstract
Lysosomal transmembrane acetylation of heparan sulfates (HS) is catalyzed by HS acetyl-CoA:α-glucosaminide N-acetyltransferase (HGSNAT), whose dysfunction leads to lysosomal storage diseases. The mechanism by which HGSNAT, the sole non-hydrolase enzyme in HS degradation, brings cytosolic acetyl-coenzyme A (Ac-CoA) and lysosomal HS together for N-acyltransferase reactions remains unclear. Here, we present cryogenic-electron microscopy structures of HGSNAT alone, complexed with Ac-CoA and with acetylated products. These structures explain that Ac-CoA binding from the cytosolic side causes dimeric HGSNAT to form a transmembrane tunnel. Within this tunnel, catalytic histidine and asparagine approach the lumen and instigate the transfer of the acetyl group from Ac-CoA to the glucosamine group of HS. Our study unveils a transmembrane acetylation mechanism that may help advance therapeutic strategies targeting lysosomal storage diseases.
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Affiliation(s)
- Ruisheng Xu
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yingjie Ning
- School of Life Science and Technology, ShanghaiTech University, Shanghai, China
| | - Fandong Ren
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, China
| | - Chenxia Gu
- School of Life Science and Technology, ShanghaiTech University, Shanghai, China
| | - Zhengjiang Zhu
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, China
| | - Xuefang Pan
- Department of Pediatrics, Centre Hospitalier Universitaire Sainte-Justine Research Centre, University of Montreal, Montreal, Quebec, Canada
| | - Alexey V Pshezhetsky
- Department of Pediatrics, Centre Hospitalier Universitaire Sainte-Justine Research Centre, University of Montreal, Montreal, Quebec, Canada.
- Department of Anatomy and Cell Biology, McGill University, Montreal, Quebec, Canada.
| | - Jingpeng Ge
- School of Life Science and Technology, ShanghaiTech University, Shanghai, China.
| | - Jie Yu
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, China.
- Shanghai Key Laboratory of Aging Studies, Shanghai, China.
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6
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Wang H, Abe I. Recent developments in the enzymatic modifications of steroid scaffolds. Org Biomol Chem 2024; 22:3559-3583. [PMID: 38639195 DOI: 10.1039/d4ob00327f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/20/2024]
Abstract
Steroids are an important family of bioactive compounds. Steroid drugs are renowned for their multifaceted pharmacological activities and are the second-largest category in the global pharmaceutical market. Recent developments in biocatalysis and biosynthesis have led to the increased use of enzymes to enhance the selectivity, efficiency, and sustainability for diverse modifications of steroids. This review discusses the advancements achieved over the past five years in the enzymatic modifications of steroid scaffolds, focusing on enzymatic hydroxylation, reduction, dehydrogenation, cascade reactions, and other modifications for future research on the synthesis of novel steroid compounds and related drugs, and new therapeutic possibilities.
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Affiliation(s)
- Huibin Wang
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
| | - Ikuro Abe
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
- Collaborative Research Institute for Innovative Microbiology, The University of Tokyo, Yayoi 1-1-1, Bunkyo-ku, Tokyo 113-8657, Japan
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7
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Sapia J, Vanni S. Molecular dynamics simulations of intracellular lipid droplets: a new tool in the toolbox. FEBS Lett 2024; 598:1143-1153. [PMID: 38627196 DOI: 10.1002/1873-3468.14879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Revised: 03/14/2024] [Accepted: 03/25/2024] [Indexed: 05/25/2024]
Abstract
Lipid droplets (LDs) are ubiquitous intracellular organelles with a central role in multiple lipid metabolic pathways. However, identifying correlations between their structural properties and their biological activity has proved challenging, owing to their unique physicochemical properties as compared with other cellular membranes. In recent years, molecular dynamics (MD) simulations, a computational methodology allowing the accurate description of molecular assemblies down to their individual components, have been demonstrated to be a useful and powerful approach for studying LD structural and dynamical properties. In this short review, we attempt to highlight, as comprehensively as possible, how MD simulations have contributed to our current understanding of multiple molecular mechanisms involved in LD biology.
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Affiliation(s)
- Jennifer Sapia
- Department of Biology, University of Fribourg, Fribourg, Switzerland
| | - Stefano Vanni
- Department of Biology, University of Fribourg, Fribourg, Switzerland
- Université Côte d'Azur, Inserm, CNRS, Institut de Pharmacologie Moléculaire et Cellulaire, Valbonne, France
- Swiss National Center for Competence in Research (NCCR) Bio-inspired Materials, University of Fribourg, Fribourg, Switzerland
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8
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Dudka W, Salo VT, Mahamid J. Zooming into lipid droplet biology through the lens of electron microscopy. FEBS Lett 2024; 598:1127-1142. [PMID: 38726814 DOI: 10.1002/1873-3468.14899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Revised: 04/08/2024] [Accepted: 04/24/2024] [Indexed: 05/25/2024]
Abstract
Electron microscopy (EM), in its various flavors, has significantly contributed to our understanding of lipid droplets (LD) as central organelles in cellular metabolism. For example, EM has illuminated that LDs, in contrast to all other cellular organelles, are uniquely enclosed by a single phospholipid monolayer, revealed the architecture of LD contact sites with different organelles, and provided near-atomic resolution maps of key enzymes that regulate neutral lipid biosynthesis and LD biogenesis. In this review, we first provide a brief history of pivotal findings in LD biology unveiled through the lens of an electron microscope. We describe the main EM techniques used in the context of LD research and discuss their current capabilities and limitations, thereby providing a foundation for utilizing suitable EM methodology to address LD-related questions with sufficient level of structural preservation, detail, and resolution. Finally, we highlight examples where EM has recently been and is expected to be instrumental in expanding the frontiers of LD biology.
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Affiliation(s)
- Wioleta Dudka
- Structural and Computational Biology Unit, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | - Veijo T Salo
- Structural and Computational Biology Unit, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | - Julia Mahamid
- Structural and Computational Biology Unit, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
- Cell Biology and Biophysics Unit, EMBL, Heidelberg, Germany
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9
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Zhang P, Liu Z. Structural insights into the transporting and catalyzing mechanism of DltB in LTA D-alanylation. Nat Commun 2024; 15:3404. [PMID: 38649359 PMCID: PMC11035591 DOI: 10.1038/s41467-024-47783-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Accepted: 04/12/2024] [Indexed: 04/25/2024] Open
Abstract
DltB, a model member of the Membrane-Bound O-AcylTransferase (MBOAT) superfamily, plays a crucial role in D-alanylation of the lipoteichoic acid (LTA), a significant component of the cell wall of gram-positive bacteria. This process stabilizes the cell wall structure, influences bacterial virulence, and modulates the host immune response. Despite its significance, the role of DltB is not well understood. Through biochemical analysis and cryo-EM imaging, we discover that Streptococcus thermophilus DltB forms a homo-tetramer on the cell membrane. We further visualize DltB in an apo form, in complex with DltC, and in complex with its inhibitor amsacrine (m-AMSA). Each tetramer features a central hole. The C-tunnel of each protomer faces the intratetramer interface and provides access to the periphery membrane. Each protomer binds a DltC without changing the tetrameric organization. A phosphatidylglycerol (PG) molecule in the substrate-binding site may serve as an LTA carrier. The inhibitor m-AMSA bound to the L-tunnel of each protomer blocks the active site. The tetrameric organization of DltB provides a scaffold for catalyzing D-alanyl transfer and regulating the channel opening and closing. Our findings unveil DltB's dual function in the D-alanylation pathway, and provide insight for targeting DltB as a anti-virulence antibiotic.
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Affiliation(s)
- Pingfeng Zhang
- Cancer Center, Renmin Hospital of Wuhan University, Wuhan, China.
| | - Zheng Liu
- Kobilka Institute of Innovative Drug Discovery, School of Medicine, The Chinese University of Hong Kong, Shenzhen, Shenzhen, China.
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10
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Mathiowetz AJ, Olzmann JA. Lipid droplets and cellular lipid flux. Nat Cell Biol 2024; 26:331-345. [PMID: 38454048 PMCID: PMC11228001 DOI: 10.1038/s41556-024-01364-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2023] [Accepted: 01/24/2024] [Indexed: 03/09/2024]
Abstract
Lipid droplets are dynamic organelles that store neutral lipids, serve the metabolic needs of cells, and sequester lipids to prevent lipotoxicity and membrane damage. Here we review the current understanding of the mechanisms of lipid droplet biogenesis and turnover, the transfer of lipids and metabolites at membrane contact sites, and the role of lipid droplets in regulating fatty acid flux in lipotoxicity and cell death.
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Affiliation(s)
- Alyssa J Mathiowetz
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA, USA
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, Berkeley, CA, USA
| | - James A Olzmann
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA, USA.
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, Berkeley, CA, USA.
- Chan Zuckerberg Biohub - San Francisco, San Francisco, CA, USA.
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11
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Clark AM, Yu D, Neiswanger G, Zhu D, Zou J, Maschek JA, Burgoyne T, Yang J. Disruption of CFAP418 interaction with lipids causes widespread abnormal membrane-associated cellular processes in retinal degenerations. JCI Insight 2024; 9:e162621. [PMID: 37971880 PMCID: PMC10906455 DOI: 10.1172/jci.insight.162621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Accepted: 11/15/2023] [Indexed: 11/19/2023] Open
Abstract
Syndromic ciliopathies and retinal degenerations are large heterogeneous groups of genetic diseases. Pathogenic variants in the CFAP418 gene may cause both disorders, and its protein sequence is evolutionarily conserved. However, the disease mechanism underlying CFAP418 mutations has not been explored. Here, we apply quantitative lipidomic, proteomic, and phosphoproteomic profiling and affinity purification coupled with mass spectrometry to address the molecular function of CFAP418 in the retina. We show that CFAP418 protein binds to the lipid metabolism precursor phosphatidic acid (PA) and mitochondrion-specific lipid cardiolipin but does not form a tight and static complex with proteins. Loss of Cfap418 in mice disturbs membrane lipid homeostasis and membrane-protein associations, which subsequently causes mitochondrial defects and membrane-remodeling abnormalities across multiple vesicular trafficking pathways in photoreceptors, especially the endosomal sorting complexes required for transport (ESCRT) pathway. Ablation of Cfap418 also increases the activity of PA-binding protein kinase Cα in the retina. Overall, our results indicate that membrane lipid imbalance is a pathological mechanism underlying syndromic ciliopathies and retinal degenerations which is associated with other known causative genes of these diseases.
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Affiliation(s)
- Anna M. Clark
- Department of Ophthalmology and Visual Sciences, Moran Eye Center, and
| | - Dongmei Yu
- Department of Ophthalmology and Visual Sciences, Moran Eye Center, and
| | - Grace Neiswanger
- Department of Ophthalmology and Visual Sciences, Moran Eye Center, and
| | - Daniel Zhu
- Department of Ophthalmology and Visual Sciences, Moran Eye Center, and
| | - Junhuang Zou
- Department of Ophthalmology and Visual Sciences, Moran Eye Center, and
| | - J. Alan Maschek
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah, USA
| | - Thomas Burgoyne
- UCL Institute of Ophthalmology, University College of London, London, United Kingdom
| | - Jun Yang
- Department of Ophthalmology and Visual Sciences, Moran Eye Center, and
- Department of Otolaryngology, and
- Department of Neurobiology, University of Utah, Salt Lake City, Utah, USA
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12
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Marongiu L, Burkard M, Helling T, Biendl M, Venturelli S. Modulation of the replication of positive-sense RNA viruses by the natural plant metabolite xanthohumol and its derivatives. Crit Rev Food Sci Nutr 2023:1-15. [PMID: 37942943 DOI: 10.1080/10408398.2023.2275169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2023]
Abstract
The COVID-19 pandemic has highlighted the importance of identifying new potent antiviral agents. Nutrients as well as plant-derived substances are promising candidates because they are usually well tolerated by the human body and readily available in nature, and consequently mostly cheap to produce. A variety of antiviral effects have recently been described for the hop chalcone xanthohumol (XN), and to a lesser extent for its derivatives, making these hop compounds particularly attractive for further investigation. Noteworthy, mounting evidence indicated that XN can suppress a wide range of viruses belonging to several virus families, all of which share a common reproductive cycle. As a result, the purpose of this review is to summarize the most recent research on the antiviral properties of XN and its derivatives, with a particular emphasis on the positive-sense RNA viruses human hepatitis C virus (HCV), porcine reproductive and respiratory syndrome virus (PRRSV), and severe acute respiratory syndrome corona virus (SARS-CoV-2).
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Affiliation(s)
- Luigi Marongiu
- Department of Nutritional Biochemistry, University of Hohenheim, Stuttgart, Germany
- HoLMiR-Hohenheim Center for Livestock Microbiome Research, University of Hohenheim, Stuttgart, Germany
| | - Markus Burkard
- Department of Nutritional Biochemistry, University of Hohenheim, Stuttgart, Germany
| | - Thomas Helling
- Department of Nutritional Biochemistry, University of Hohenheim, Stuttgart, Germany
| | - Martin Biendl
- HHV Hallertauer Hopfenveredelungsgesellschaft m.b.H, Mainburg, Germany
| | - Sascha Venturelli
- Department of Nutritional Biochemistry, University of Hohenheim, Stuttgart, Germany
- Department of Vegetative and Clinical Physiology, University Hospital of Tuebingen, Tuebingen, Germany
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13
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Zhu H, Ahmad S, Duan Z, Shi J, Tang X, Dong Q, Xi C, Ge L, Wu T, Tan Y. The Jinggangmycin-induced Mthl2 gene regulates the development and stress resistance in Nilaparvata lugens Stål (Hemiptera: Delphacidae). PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2023; 196:105630. [PMID: 37945234 DOI: 10.1016/j.pestbp.2023.105630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 09/23/2023] [Accepted: 09/25/2023] [Indexed: 11/12/2023]
Abstract
Methuselah (Mth) belongs to the GPCR family B, which regulates various biological processes and stress responses. The previous transcriptome data showed jinggangmycin (JGM)-induced Mthl2 expression. However, its detailed functional role remained unclear in brown planthopper, Nilaparvata lugens Stål. In adult N. lugens, the Mthl2 gene showed dominant expressions, notably in ovaries and fat body tissues. The 3rd instar nymphs treated with JGM increased starvation, oxidative stress, and high temperature (34 °C) tolerance of the adults. On the contrary, under dsMthl2 treatment, completely opposite phenotypes were observed. The lipid synthesis genes (DGAT1and PNPLA3) of both females and males treated with JGM in the nymphal stage were observed with high expressions, while the lipolysis of the Lipase 3 gene was observed with low expressions. The JGM increased triglyceride (TG) content, fat body droplet size, and the number of fat body droplets. The same treatment also increased the Glutathione S-transferase (GST), catalase (CAT), and superoxide dismutase (SOD) activities. An increase in the heat shock protein (HSP70 and HSP90) expression levels was also observed under JGM treatment but not dsMthl2. The current study demonstrated the influential role of the Mthl genes, particularly the Mthl2 gene, in modulating the growth and development and stress-responsiveness in N. lugens. Thus, providing a platform for future applied research programs controlling N. lugens population in rice fields.
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Affiliation(s)
- Haowen Zhu
- College of Plant Protection, Yangzhou University, 225009 Yangzhou, PR China
| | - Sheraz Ahmad
- College of Plant Protection, Yangzhou University, 225009 Yangzhou, PR China
| | - Zhirou Duan
- College of Plant Protection, Yangzhou University, 225009 Yangzhou, PR China
| | - Junting Shi
- College of Plant Protection, Yangzhou University, 225009 Yangzhou, PR China
| | - Xingyu Tang
- College of Plant Protection, Yangzhou University, 225009 Yangzhou, PR China
| | - Qiaoqiao Dong
- College of Plant Protection, Yangzhou University, 225009 Yangzhou, PR China
| | - Chuanyuan Xi
- College of Plant Protection, Yangzhou University, 225009 Yangzhou, PR China
| | - Linquan Ge
- College of Plant Protection, Yangzhou University, 225009 Yangzhou, PR China.
| | - Tao Wu
- College of Horticulture and Landscape Architecture, Yangzhou University, 225009 Yangzhou, PR China.
| | - Yongan Tan
- Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, PR China.
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14
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Koch M, Tebben J, Saborowski R. Diacylglycerol acyltransferase (DGAT) in Crangon crangon and Pandalus montagui (Decapoda, Caridea) - Implications for lipid storage capacities and life history traits. Comp Biochem Physiol B Biochem Mol Biol 2023; 268:110878. [PMID: 37481107 DOI: 10.1016/j.cbpb.2023.110878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 07/13/2023] [Accepted: 07/13/2023] [Indexed: 07/24/2023]
Abstract
Lipids play essential roles in cell-structuring, cell-signaling, and as efficient metabolic energy stores. Lipid storage capacities determine life history traits of organisms and, thus, their ecological function. Among storage lipids, triacylglycerols (TAGs) are widespread in marine invertebrates. However, abilities to accumulate TAGs can vary even between closely related species, such as the caridean shrimps Crangon crangon and Pandalus montagui. The first species shows low TAG levels throughout the year in the main storage organ, the midgut gland, while the latter accumulates high TAG-levels, peaking in summer. TAGs synthesis is facilitated by the terminal step of the Kennedy-pathway, where the enzyme diacylglycerol-acyltransferase (DGAT) catalyzes the esterification of diacylglycerols with activated fatty acids. We investigated DGAT activity in the midgut gland using a fluorescent enzyme assay. Sequence information was extracted from whole transcriptome shotgun assembly data, that is publicly available on NCBI, and catalytic properties were deduced from molecular structure analysis. C. crangon showed significantly lower TAG synthesis rates than P. montagui, which explains the native TAG levels. Transcriptome data yielded several isoforms of DGAT enzymes in both species. C. crangon DGAT showed point mutations, which are capable of obstructing the catalytic capacity. The consequences are limited starvation resistance and, thus, presumably restricting C. crangon to a habitat with year-round sufficient food. In contrast, higher TAG synthesis rates presumably enable P. montagui to extend into northern subarctic habitats with limited food availability in winter. Moreover, the limited TAG synthesis and accumulation in the midgut gland may force C. crangon to direct energy into the ovaries, which results in multiple spawnings.
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Affiliation(s)
- Marie Koch
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Am Handelshafen 12, 27570 Bremerhaven, Germany; University of Bremen, Faculty 2 Biology/Chemistry, Leobener Str., 28359 Bremen, Germany.
| | - Jan Tebben
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Am Handelshafen 12, 27570 Bremerhaven, Germany.
| | - Reinhard Saborowski
- Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Am Handelshafen 12, 27570 Bremerhaven, Germany.
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15
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McLelland GL, Lopez-Osias M, Verzijl CRC, Ellenbroek BD, Oliveira RA, Boon NJ, Dekker M, van den Hengel LG, Ali R, Janssen H, Song JY, Krimpenfort P, van Zutphen T, Jonker JW, Brummelkamp TR. Identification of an alternative triglyceride biosynthesis pathway. Nature 2023; 621:171-178. [PMID: 37648867 PMCID: PMC10482677 DOI: 10.1038/s41586-023-06497-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 07/28/2023] [Indexed: 09/01/2023]
Abstract
Triacylglycerols (TAGs) are the main source of stored energy in the body, providing an important substrate pool for mitochondrial beta-oxidation. Imbalances in the amount of TAGs are associated with obesity, cardiac disease and various other pathologies1,2. In humans, TAGs are synthesized from excess, coenzyme A-conjugated fatty acids by diacylglycerol O-acyltransferases (DGAT1 and DGAT2)3. In other organisms, this activity is complemented by additional enzymes4, but whether such alternative pathways exist in humans remains unknown. Here we disrupt the DGAT pathway in haploid human cells and use iterative genetics to reveal an unrelated TAG-synthesizing system composed of a protein we called DIESL (also known as TMEM68, an acyltransferase of previously unknown function) and its regulator TMX1. Mechanistically, TMX1 binds to and controls DIESL at the endoplasmic reticulum, and loss of TMX1 leads to the unconstrained formation of DIESL-dependent lipid droplets. DIESL is an autonomous TAG synthase, and expression of human DIESL in Escherichia coli endows this organism with the ability to synthesize TAG. Although both DIESL and the DGATs function as diacylglycerol acyltransferases, they contribute to the cellular TAG pool under specific conditions. Functionally, DIESL synthesizes TAG at the expense of membrane phospholipids and maintains mitochondrial function during periods of extracellular lipid starvation. In mice, DIESL deficiency impedes rapid postnatal growth and affects energy homeostasis during changes in nutrient availability. We have therefore identified an alternative TAG biosynthetic pathway driven by DIESL under potent control by TMX1.
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Affiliation(s)
- Gian-Luca McLelland
- Oncode Institute, Division of Biochemistry, The Netherlands Cancer Institute, Amsterdam, The Netherlands.
| | - Marta Lopez-Osias
- Oncode Institute, Division of Biochemistry, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Cristy R C Verzijl
- Department of Pediatrics, Section of Molecular Metabolism and Nutrition, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Brecht D Ellenbroek
- Oncode Institute, Division of Biochemistry, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Rafaela A Oliveira
- Oncode Institute, Division of Biochemistry, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Nicolaas J Boon
- Oncode Institute, Division of Biochemistry, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Marleen Dekker
- Oncode Institute, Division of Biochemistry, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Lisa G van den Hengel
- Oncode Institute, Division of Biochemistry, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Rahmen Ali
- Animal Modeling Facility, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Hans Janssen
- Electron Microscope Facility, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Ji-Ying Song
- Animal Pathology, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Paul Krimpenfort
- Animal Modeling Facility, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Tim van Zutphen
- Department of Pediatrics, Section of Molecular Metabolism and Nutrition, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
- Faculty Campus Fryslân, University of Groningen, Leeuwarden, The Netherlands
| | - Johan W Jonker
- Department of Pediatrics, Section of Molecular Metabolism and Nutrition, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Thijn R Brummelkamp
- Oncode Institute, Division of Biochemistry, The Netherlands Cancer Institute, Amsterdam, The Netherlands.
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16
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Campaña M, Davis TR, Novak SX, Cleverdon ER, Bates M, Krishnan N, Curtis ER, Childs MD, Pierce MR, Morales-Rodriguez Y, Sieburg MA, Hehnly H, Luyt LG, Hougland JL. Cellular Uptake of a Fluorescent Ligand Reveals Ghrelin O-Acyltransferase Interacts with Extracellular Peptides and Exhibits Unexpected Localization for a Secretory Pathway Enzyme. ACS Chem Biol 2023; 18:1880-1890. [PMID: 37494676 PMCID: PMC10442857 DOI: 10.1021/acschembio.3c00334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Accepted: 07/17/2023] [Indexed: 07/28/2023]
Abstract
Ghrelin O-acyltransferase (GOAT) plays a central role in the maturation and activation of the peptide hormone ghrelin, which performs a wide range of endocrinological signaling roles. Using a tight-binding fluorescent ghrelin-derived peptide designed for high selectivity for GOAT over the ghrelin receptor GHSR, we demonstrate that GOAT interacts with extracellular ghrelin and facilitates ligand cell internalization in both transfected cells and prostate cancer cells endogenously expressing GOAT. Coupled with enzyme mutagenesis, ligand uptake studies support the interaction of the putative histidine general base within GOAT with the ghrelin peptide acylation site. Our work provides a new understanding of GOAT's catalytic mechanism, establishes that GOAT can interact with ghrelin and other peptides located outside the cell, and raises the possibility that other peptide hormones may exhibit similar complexity in their intercellular and organismal-level signaling pathways.
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Affiliation(s)
- Maria
B. Campaña
- Department
of Chemistry, Syracuse University, Syracuse, New York 13244, United States
| | - Tasha R. Davis
- Department
of Chemistry, Syracuse University, Syracuse, New York 13244, United States
| | - Sadie X. Novak
- Department
of Chemistry, Syracuse University, Syracuse, New York 13244, United States
| | | | - Michael Bates
- Department
of Biology, Syracuse University, Syracuse, New York 13244, United States
| | - Nikhila Krishnan
- Department
of Biology, Syracuse University, Syracuse, New York 13244, United States
| | - Erin R. Curtis
- Department
of Biology, Syracuse University, Syracuse, New York 13244, United States
| | - Marina D. Childs
- Department
of Chemistry, University of Western Ontario, London, Ontario N6A 2K7, Canada
| | - Mariah R. Pierce
- Department
of Chemistry, Syracuse University, Syracuse, New York 13244, United States
| | | | - Michelle A. Sieburg
- Department
of Chemistry, Syracuse University, Syracuse, New York 13244, United States
| | - Heidi Hehnly
- Department
of Biology, Syracuse University, Syracuse, New York 13244, United States
- BioInspired
Syracuse, Syracuse University, Syracuse, New York 13244, United States
| | - Leonard G. Luyt
- Department
of Chemistry, University of Western Ontario, London, Ontario N6A 2K7, Canada
- Department
of Oncology and Department of Medical Imaging, London Regional Cancer
Program, Lawson Health Research Institute, 800 Commissioners Road East, London, Ontario N6A 5W9, Canada
| | - James L. Hougland
- Department
of Chemistry, Syracuse University, Syracuse, New York 13244, United States
- Department
of Biology, Syracuse University, Syracuse, New York 13244, United States
- BioInspired
Syracuse, Syracuse University, Syracuse, New York 13244, United States
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17
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Schultz BJ, Snow ED, Walker S. Mechanism of D-alanine transfer to teichoic acids shows how bacteria acylate cell envelope polymers. Nat Microbiol 2023; 8:1318-1329. [PMID: 37308592 PMCID: PMC10664464 DOI: 10.1038/s41564-023-01411-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Accepted: 05/17/2023] [Indexed: 06/14/2023]
Abstract
Bacterial cell envelope polymers are often modified with acyl esters that modulate physiology, enhance pathogenesis and provide antibiotic resistance. Here, using the D-alanylation of lipoteichoic acid (Dlt) pathway as a paradigm, we have identified a widespread strategy for how acylation of cell envelope polymers occurs. In this strategy, a membrane-bound O-acyltransferase (MBOAT) protein transfers an acyl group from an intracellular thioester onto the tyrosine of an extracytoplasmic C-terminal hexapeptide motif. This motif shuttles the acyl group to a serine on a separate transferase that moves the cargo to its destination. In the Dlt pathway, here studied in Staphylococcus aureus and Streptococcus thermophilus, the C-terminal 'acyl shuttle' motif that forms the crucial pathway intermediate is found on a transmembrane microprotein that holds the MBOAT protein and the other transferase together in a complex. In other systems, found in both Gram-negative and Gram-positive bacteria as well as some archaea, the motif is fused to the MBOAT protein, which interacts directly with the other transferase. The conserved chemistry uncovered here is widely used for acylation throughout the prokaryotic world.
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Affiliation(s)
- Bailey J Schultz
- Department of Microbiology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Eric D Snow
- Department of Microbiology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
| | - Suzanne Walker
- Department of Microbiology, Blavatnik Institute, Harvard Medical School, Boston, MA, USA.
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18
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Wang K, Lee CW, Sui X, Kim S, Wang S, Higgs AB, Baublis AJ, Voth GA, Liao M, Walther TC, Farese RV. The structure of phosphatidylinositol remodeling MBOAT7 reveals its catalytic mechanism and enables inhibitor identification. Nat Commun 2023; 14:3533. [PMID: 37316513 PMCID: PMC10267149 DOI: 10.1038/s41467-023-38932-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Accepted: 05/22/2023] [Indexed: 06/16/2023] Open
Abstract
Cells remodel glycerophospholipid acyl chains via the Lands cycle to adjust membrane properties. Membrane-bound O-acyltransferase (MBOAT) 7 acylates lyso-phosphatidylinositol (lyso-PI) with arachidonyl-CoA. MBOAT7 mutations cause brain developmental disorders, and reduced expression is linked to fatty liver disease. In contrast, increased MBOAT7 expression is linked to hepatocellular and renal cancers. The mechanistic basis of MBOAT7 catalysis and substrate selectivity are unknown. Here, we report the structure and a model for the catalytic mechanism of human MBOAT7. Arachidonyl-CoA and lyso-PI access the catalytic center through a twisted tunnel from the cytosol and lumenal sides, respectively. N-terminal residues on the ER lumenal side determine phospholipid headgroup selectivity: swapping them between MBOATs 1, 5, and 7 converts enzyme specificity for different lyso-phospholipids. Finally, the MBOAT7 structure and virtual screening enabled identification of small-molecule inhibitors that may serve as lead compounds for pharmacologic development.
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Affiliation(s)
- Kun Wang
- Department of Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA, USA
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Chia-Wei Lee
- Department of Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA, USA
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Xuewu Sui
- Department of Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA, USA
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
- Department of Biochemistry and Biophysics, College of Agriculture and Life Sciences, Texas A&M University, College Station, TX, USA
| | - Siyoung Kim
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL, USA
| | - Shuhui Wang
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Aidan B Higgs
- Department of Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA, USA
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Aaron J Baublis
- Department of Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA, USA
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
- Harvard T.H. Chan Advanced Multi-Omics Platform, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Gregory A Voth
- Department of Chemistry, Chicago Center for Theoretical Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, Chicago, IL, USA
| | - Maofu Liao
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA.
- School of Life Sciences, Southern University of Science and Technology, Shenzhen, China.
| | - Tobias C Walther
- Department of Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA, USA.
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA.
- Harvard T.H. Chan Advanced Multi-Omics Platform, Harvard T.H. Chan School of Public Health, Boston, MA, USA.
- Broad Institute of MIT and Harvard, Cambridge, MA, USA.
- Howard Hughes Medical Institute, Boston, MA, USA.
- Cell Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
| | - Robert V Farese
- Department of Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA, USA.
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA.
- Broad Institute of MIT and Harvard, Cambridge, MA, USA.
- Cell Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
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19
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Greenwood BL, Luo Z, Ahmed T, Huang D, Stuart DT. Saccharomyces cerevisiae Δ9-desaturase Ole1 forms a supercomplex with Slc1 and Dga1. J Biol Chem 2023:104882. [PMID: 37269945 PMCID: PMC10302205 DOI: 10.1016/j.jbc.2023.104882] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2022] [Revised: 05/04/2023] [Accepted: 05/07/2023] [Indexed: 06/05/2023] Open
Abstract
Biosynthesis of the various lipid species that compose cellular membranes and lipid droplets depends on the activity of multiple enzymes functioning in coordinated pathways. The flux of intermediates through lipid biosynthetic pathways is regulated to respond to nutritional and environmental demands placed on the cell necessitating that there be extensive flexibility in pathway activity and organization. This flexibility can in part be achieved through the organization of biosynthetic enzymes into metabolon supercomplexes. However, the composition and organization of such supercomplexes remains unclear. Here, we identified protein-protein interactions between acyltransferases Sct1, Gpt2, Slc1, Dga1 and the Δ9 acyl-CoA desaturase Ole1 in Saccharomyces cerevisiae. We further determined that a subset of these acyltransferases interact with each other without Ole1 acting as a scaffold. We show that truncated versions of Dga1 lacking the carboxyl-terminal 20 amino acid residues are non-functional and unable to bind Ole1. Furthermore, charged-to-alanine scanning mutagenesis revealed that a cluster of charged residues near the carboxyl-terminus were required for the interaction with Ole1. Mutation of these charged residues disrupted the interaction between Dga1 and Ole1, but allowed Dga1 to retain catalytic activity and to induce lipid droplet formation. These data support the formation of a complex of acyltransferases involved in lipid biosynthesis that interacts with Ole1, the sole acyl-CoA desaturase in S. cerevisiae, that can channel unsaturated acyl-chains toward phospholipid or triacylglycerol synthesis. This desaturasome complex may provide the architecture that allows for the necessary flux of de novo synthesized unsaturated acyl-CoA to phospholipid or triacylglycerol synthesis as demanded by cellular requirements.
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Affiliation(s)
- Brianna L Greenwood
- Department of Biochemistry, 561 Medical Sciences Building, University of Alberta, Edmonton AB, T6G 2R3, Canada
| | - Zijun Luo
- Department of Biochemistry, 561 Medical Sciences Building, University of Alberta, Edmonton AB, T6G 2R3, Canada
| | - Tareq Ahmed
- Department of Biochemistry, 561 Medical Sciences Building, University of Alberta, Edmonton AB, T6G 2R3, Canada
| | - Daniel Huang
- Department of Biochemistry, 561 Medical Sciences Building, University of Alberta, Edmonton AB, T6G 2R3, Canada
| | - David T Stuart
- Department of Biochemistry, 561 Medical Sciences Building, University of Alberta, Edmonton AB, T6G 2R3, Canada.
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20
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Coupland CE, Ansell TB, Sansom MSP, Siebold C. Rocking the MBOAT: Structural insights into the membrane bound O-acyltransferase family. Curr Opin Struct Biol 2023; 80:102589. [PMID: 37040671 DOI: 10.1016/j.sbi.2023.102589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 02/28/2023] [Accepted: 03/06/2023] [Indexed: 04/13/2023]
Abstract
The membrane-bound O-acyltransferase (MBOAT) superfamily catalyses the transfer of acyl chains to substrates implicated in essential cellular functions. Aberrant function of MBOATs is associated with various diseases and MBOATs are promising drug targets. There has been recent progress in structural characterisation of MBOATs, advancing our understanding of their functional mechanism. Integrating information across the MBOAT family, we characterise a common MBOAT fold and provide a blueprint for substrate and inhibitor engagement. This work provides context for the diverse substrates, mechanisms, and evolutionary relationships of protein and small-molecule MBOATs. Further work should aim to characterise MBOATs, as inherently lipid-associated proteins, within their membrane environment.
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Affiliation(s)
- Claire E Coupland
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
| | - T Bertie Ansell
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK; Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK
| | - Mark S P Sansom
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK.
| | - Christian Siebold
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK.
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21
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Walther TC, Kim S, Arlt H, Voth GA, Farese RV. Structure and function of lipid droplet assembly complexes. Curr Opin Struct Biol 2023; 80:102606. [PMID: 37150040 PMCID: PMC10853036 DOI: 10.1016/j.sbi.2023.102606] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 04/03/2023] [Accepted: 04/10/2023] [Indexed: 05/09/2023]
Abstract
Cells store lipids as a reservoir of metabolic energy and membrane component precursors in organelles called lipid droplets (LDs). LD formation occurs in the endoplasmic reticulum (ER) at LD assembly complexes (LDAC), consisting of an oligomeric core of seipin and accessory proteins. LDACs determine the sites of LD formation and are required for this process to occur normally. Seipin oligomers form a cage-like structure in the membrane that may serve to facilitate the phase transition of neutral lipids in the membrane to form an oil droplet within the LDAC. Modeling suggests that, as the LD grows, seipin anchors it to the ER bilayer and conformational shifts of seipin transmembrane segments open the LDAC dome toward the cytoplasm, enabling the emerging LD to egress from the ER.
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Affiliation(s)
- Tobias C Walther
- Cell Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA; Howard Hughes Medical Institute, New York, NY 10065, USA.
| | - Siyoung Kim
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL, 60637, USA
| | - Henning Arlt
- Howard Hughes Medical Institute, New York, NY 10065, USA
| | - Gregory A Voth
- Department of Chemistry, Chicago Center for Theoretical Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, University of Chicago, Chicago, IL, 60637, USA
| | - Robert V Farese
- Cell Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
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22
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Henne WM. The (social) lives, deaths, and biophysical phases of lipid droplets. Curr Opin Cell Biol 2023; 82:102178. [PMID: 37295067 PMCID: PMC10782554 DOI: 10.1016/j.ceb.2023.102178] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Revised: 05/18/2023] [Accepted: 05/19/2023] [Indexed: 06/12/2023]
Abstract
Lipid droplets (LDs) are major lipid storage organelles, sequestering energy-rich triglycerides and serving as nutrient sinks for cellular homeostasis. Observed for over a century but generally ignored, LDs are now appreciated to play key roles in organismal physiology and disease. They also form numerous functional contacts with other organelles. Here, we highlight recent studies examining LDs from distinct perspectives of their life cycle: their biogenesis, "social" life as they interact with other organelles, and deaths via lipolysis or lipophagy. We also discuss recent work showing how changes in LD lipid content alter the biophysical phases of LD lipids, and how this may fine-tune the LD protein landscape and ultimately LD function.
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Affiliation(s)
- W Mike Henne
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX 75390, USA.
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23
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Sui X, Wang K, Song K, Xu C, Song J, Lee CW, Liao M, Farese RV, Walther TC. Mechanism of action for small-molecule inhibitors of triacylglycerol synthesis. Nat Commun 2023; 14:3100. [PMID: 37248213 PMCID: PMC10227072 DOI: 10.1038/s41467-023-38934-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Accepted: 05/23/2023] [Indexed: 05/31/2023] Open
Abstract
Inhibitors of triacylglycerol (TG) synthesis have been developed to treat metabolism-related diseases, but we know little about their mechanisms of action. Here, we report cryo-EM structures of the TG-synthesis enzyme acyl-CoA:diacylglycerol acyltransferase 1 (DGAT1), a membrane bound O-acyltransferase (MBOAT), in complex with two different inhibitors, T863 and DGAT1IN1. Each inhibitor binds DGAT1's fatty acyl-CoA substrate binding tunnel that opens to the cytoplasmic side of the ER. T863 blocks access to the tunnel entrance, whereas DGAT1IN1 extends further into the enzyme, with an amide group interacting with more deeply buried catalytic residues. A survey of DGAT1 inhibitors revealed that this amide group may serve as a common pharmacophore for inhibition of MBOATs. The inhibitors were minimally active against the related MBOAT acyl-CoA:cholesterol acyltransferase 1 (ACAT1), yet a single-residue mutation sensitized ACAT1 for inhibition. Collectively, our studies provide a structural foundation for developing DGAT1 and other MBOAT inhibitors.
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Affiliation(s)
- Xuewu Sui
- Department of Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA, USA
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
- Department of Biochemistry and Biophysics, College of Agriculture and Life Sciences, Texas A&M University, College Station, TX, USA
| | - Kun Wang
- Department of Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA, USA
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Kangkang Song
- Department of Biochemistry and Molecular Biotechnology, University of Massachusetts Chan Medical School, Worcester, MA, USA
- Cryo-EM Core Facility, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Chen Xu
- Department of Biochemistry and Molecular Biotechnology, University of Massachusetts Chan Medical School, Worcester, MA, USA
- Cryo-EM Core Facility, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Jiunn Song
- Department of Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA, USA
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Chia-Wei Lee
- Department of Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA, USA
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Maofu Liao
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA.
- School of Life Sciences, Southern University of Science and Technology, Shenzhen, China.
| | - Robert V Farese
- Department of Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA, USA.
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA.
- Broad Institute of MIT and Harvard, Cambridge, MA, USA.
- Cell Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
| | - Tobias C Walther
- Department of Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA, USA.
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA.
- Broad Institute of MIT and Harvard, Cambridge, MA, USA.
- Cell Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
- Howard Hughes Medical Institute, Boston, MA, USA.
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24
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Zadoorian A, Du X, Yang H. Lipid droplet biogenesis and functions in health and disease. Nat Rev Endocrinol 2023:10.1038/s41574-023-00845-0. [PMID: 37221402 DOI: 10.1038/s41574-023-00845-0] [Citation(s) in RCA: 63] [Impact Index Per Article: 63.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/25/2023] [Indexed: 05/25/2023]
Abstract
Ubiquitous yet unique, lipid droplets are intracellular organelles that are increasingly being recognized for their versatility beyond energy storage. Advances uncovering the intricacies of their biogenesis and the diversity of their physiological and pathological roles have yielded new insights into lipid droplet biology. Despite these insights, the mechanisms governing the biogenesis and functions of lipid droplets remain incompletely understood. Moreover, the causal relationship between the biogenesis and function of lipid droplets and human diseases is poorly resolved. Here, we provide an update on the current understanding of the biogenesis and functions of lipid droplets in health and disease, highlighting a key role for lipid droplet biogenesis in alleviating cellular stresses. We also discuss therapeutic strategies of targeting lipid droplet biogenesis, growth or degradation that could be applied in the future to common diseases, such as cancer, hepatic steatosis and viral infection.
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Affiliation(s)
- Armella Zadoorian
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, Australia
| | - Ximing Du
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, Australia
| | - Hongyuan Yang
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, Australia.
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25
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Burnett AJN, Rodriguez E, Constable S, Lowrance B, Fish M, Weadge JT. WssI from the Gram-Negative Bacterial Cellulose Synthase is an O-acetyltransferase that Acts on Cello-oligomers with Several Acetyl Donor Substrates. J Biol Chem 2023:104849. [PMID: 37224964 PMCID: PMC10302187 DOI: 10.1016/j.jbc.2023.104849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Revised: 05/03/2023] [Accepted: 05/04/2023] [Indexed: 05/26/2023] Open
Abstract
In microbial biofilms, bacterial cells are encased in a self-produced matrix of polymers (e.g., exopolysaccharides) that enable surface adherence and protect against environmental stressors. For example, the wrinkly spreader phenotype of Pseudomonas fluorescens colonizes food/water sources and human tissue to form robust biofilms that can spread across surfaces. This biofilm largely consists of bacterial cellulose produced by the cellulose synthase proteins encoded by the wss operon, which also occurs in other species, including pathogenic Achromobacter species. Although phenotypic mutant analysis of the wssFGHI genes has previously shown that they are responsible for acetylation of bacterial cellulose, their specific roles remain unknown and distinct from the recently identified cellulose phosphoethanolamine modification found in other species. Here we have purified the C-terminal soluble form of WssI from P. fluorescens and A. insuavis and demonstrated acetyl-esterase activity with chromogenic substrates. The kinetic parameters (kcat/KM values of 13 and 8.0 M-1∙ s-1, respectively) indicate that these enzymes are up to four times more catalytically efficient than the closest characterized homolog, AlgJ from the alginate synthase. Unlike AlgJ and its cognate alginate polymer, WssI also demonstrated acetyltransferase activity onto cellulose oligomers (e.g., cellotetraose to cellohexaose) with multiple acetyl-donor substrates (pNP-Ac, MU-Ac and acetyl-CoA). Finally, a high-throughput screen identified three low micromolar WssI inhibitors that may be useful for chemically interrogating cellulose acetylation and biofilm formation.
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Affiliation(s)
| | - Emily Rodriguez
- Department of Biology, Wilfrid Laurier University, Waterloo, ON, Canada
| | - Shirley Constable
- Department of Biology, Wilfrid Laurier University, Waterloo, ON, Canada
| | - Brian Lowrance
- Department of Biology, Wilfrid Laurier University, Waterloo, ON, Canada
| | - Michael Fish
- Department of Biology, Wilfrid Laurier University, Waterloo, ON, Canada
| | - Joel T Weadge
- Department of Biology, Wilfrid Laurier University, Waterloo, ON, Canada.
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26
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Wang L, Zhou M. Structure of a eukaryotic cholinephosphotransferase-1 reveals mechanisms of substrate recognition and catalysis. Nat Commun 2023; 14:2753. [PMID: 37179328 PMCID: PMC10182977 DOI: 10.1038/s41467-023-38003-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Accepted: 04/03/2023] [Indexed: 05/15/2023] Open
Abstract
Phosphatidylcholine (PC) is the most abundant phospholipid in eukaryotic cell membranes. In eukaryotes, two highly homologous enzymes, cholinephosphotransferase-1 (CHPT1) and choline/ethanolamine phosphotransferase-1 (CEPT1) catalyze the final step of de novo PC synthesis. CHPT1/CEPT1 joins two substrates, cytidine diphosphate-choline (CDP-choline) and diacylglycerol (DAG), to produce PC, and Mg2+ is required for the reaction. However, mechanisms of substrate recognition and catalysis remain unresolved. Here we report structures of a CHPT1 from Xenopus laevis (xlCHPT1) determined by cryo-electron microscopy to an overall resolution of ~3.2 Å. xlCHPT1 forms a homodimer, and each protomer has 10 transmembrane helices (TMs). The first 6 TMs carve out a cone-shaped enclosure in the membrane in which the catalysis occurs. The enclosure opens to the cytosolic side, where a CDP-choline and two Mg2+ are coordinated. The structures identify a catalytic site unique to eukaryotic CHPT1/CEPT1 and suggest an entryway for DAG. The structures also reveal an internal pseudo two-fold symmetry between TM3-6 and TM7-10, and suggest that CHPT1/CEPT1 may have evolved from their distant prokaryotic ancestors through gene duplication.
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Affiliation(s)
- Lie Wang
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX, USA.
| | - Ming Zhou
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX, USA.
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27
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Pierce MR, Hougland JL. A rising tide lifts all MBOATs: recent progress in structural and functional understanding of membrane bound O-acyltransferases. Front Physiol 2023; 14:1167873. [PMID: 37250116 PMCID: PMC10213974 DOI: 10.3389/fphys.2023.1167873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Accepted: 04/19/2023] [Indexed: 05/31/2023] Open
Abstract
Acylation modifications play a central role in biological and physiological processes. Across a range of biomolecules from phospholipids to triglycerides to proteins, introduction of a hydrophobic acyl chain can dramatically alter the biological function and cellular localization of these substrates. Amongst the enzymes catalyzing these modifications, the membrane bound O-acyltransferase (MBOAT) family occupies an intriguing position as the combined substrate selectivities of the various family members span all three classes of these biomolecules. MBOAT-dependent substrates are linked to a wide range of health conditions including metabolic disease, cancer, and neurodegenerative disease. Like many integral membrane proteins, these enzymes have presented challenges to investigation due to their intractability to solubilization and purification. However, over the last several years new solubilization approaches coupled with computational modeling, crystallography, and cryoelectron microscopy have brought an explosion of structural information for multiple MBOAT family members. These studies enable comparison of MBOAT structure and function across members catalyzing modifications of all three substrate classes, revealing both conserved features amongst all MBOATs and distinct architectural features that correlate with different acylation substrates ranging from lipids to proteins. We discuss the methods that led to this renaissance of MBOAT structural investigations, our new understanding of MBOAT structure and implications for catalytic function, and the potential impact of these studies for development of new therapeutics targeting MBOAT-dependent physiological processes.
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Affiliation(s)
- Mariah R. Pierce
- Department of Chemistry, Syracuse University, Syracuse, NY, United States
| | - James L. Hougland
- Department of Chemistry, Syracuse University, Syracuse, NY, United States
- Department of Biology, Syracuse University, Syracuse, NY, United States
- BioInspired Syracuse, Syracuse University, Syracuse, NY, United States
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28
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Farese RV, Walther TC. Glycerolipid Synthesis and Lipid Droplet Formation in the Endoplasmic Reticulum. Cold Spring Harb Perspect Biol 2023; 15:a041246. [PMID: 36096640 PMCID: PMC10153804 DOI: 10.1101/cshperspect.a041246] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
More than 60 years ago, Eugene Kennedy and coworkers elucidated the endoplasmic reticulum (ER)-based pathways of glycerolipid synthesis, including the synthesis of phospholipids and triacylglycerols (TGs). The reactions of the Kennedy pathway were identified by studying the conversion of lipid intermediates and the isolation of biochemical enzymatic activities, but the molecular basis for most of these reactions was unknown. With recent progress in the cell biology, biochemistry, and structural biology in this area, we have a much more mechanistic understanding of this pathway and its reactions. In this review, we provide an overview of molecular aspects of glycerolipid synthesis, focusing on recent insights into the synthesis of TGs. Further, we go beyond the Kennedy pathway to describe the mechanisms for storage of TG in cytosolic lipid droplets and discuss how overwhelming these pathways leads to ER stress and cellular toxicity, as seen in diseases linked to lipid overload and obesity.
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Affiliation(s)
- Robert V Farese
- Department of Molecular Metabolism, Harvard T. H. Chan School of Public Health, Boston, Massachusetts 02115, USA
- Department of Cell Biology, Harvard Medical School, Boston, Massachusetts 02115, USA
- Broad Institute of Harvard and MIT, Cambridge, Massachusetts 02142, USA
- Center for Causes and Prevention of Cardiovascular Disease (CAP-CVD), Harvard T. H. Chan School of Public Health, Boston, Massachusetts 02115, USA
| | - Tobias C Walther
- Department of Molecular Metabolism, Harvard T. H. Chan School of Public Health, Boston, Massachusetts 02115, USA
- Department of Cell Biology, Harvard Medical School, Boston, Massachusetts 02115, USA
- Broad Institute of Harvard and MIT, Cambridge, Massachusetts 02142, USA
- Center for Causes and Prevention of Cardiovascular Disease (CAP-CVD), Harvard T. H. Chan School of Public Health, Boston, Massachusetts 02115, USA
- Howard Hughes Medical Institute Boston, Boston, Massachusetts 02115, USA
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29
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Li ZM, Bai F, Wang X, Xie C, Wan Y, Li Y, Liu J, Li Z. Kinetic Characterization and Catalytic Mechanism of N-Acetylornithine Aminotransferase Encoded by slr1022 Gene from Synechocystis sp. PCC6803. Int J Mol Sci 2023; 24:ijms24065853. [PMID: 36982927 PMCID: PMC10057298 DOI: 10.3390/ijms24065853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 03/17/2023] [Accepted: 03/17/2023] [Indexed: 03/30/2023] Open
Abstract
The enzyme encoded by slr1022 gene from Synechocystis sp. PCC6803 was reported to function as N-acetylornithine aminotransferase, γ-aminobutyric acid aminotransferase, and ornithine aminotransferase, which played important roles in multiple metabolic pathways. Among these functions, N-acetylornithine aminotransferase catalyzes the reversible conversion of N-acetylornithine to N-acetylglutamate-5-semialdehyde with PLP as cofactor, which is a key step in the arginine biosynthesis pathway. However, the investigation of the detailed kinetic characteristics and catalytic mechanism of Slr1022 has not been carried out yet. In this study, the exploration of kinetics of recombinant Slr1022 illustrated that Slr1022 mainly functioned as N-acetylornithine aminotransferase with low substrate specificity to γ-aminobutyric acid and ornithine. Kinetic assay of Slr1022 variants and the model structure of Slr1022 with N-acetylornithine-PLP complex revealed that Lys280 and Asp251 residues were the key amino acids of Slr1022. The respective mutation of the above two residues to Ala resulted in the activity depletion of Slr1022. Meanwhile, Glu223 residue was involved in substrate binding and it served as a switch between the two half reactions. Other residues such as Thr308, Gln254, Tyr39, Arg163, and Arg402 implicated a substrate recognition and catalytic process of the reaction. The results of this study further enriched the understanding of the catalytic kinetics and mechanism of N-acetylornithine aminotransferase, especially from cyanobacteria.
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Affiliation(s)
- Zhi-Min Li
- College of Chemistry and Materials, Jiangxi Agricultural University, Nanchang 330045, China
| | - Fumei Bai
- Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources, College of Bioscience and Bioengineering, Jiangxi Agricultural University, Nanchang 330045, China
| | - Xiaoqin Wang
- Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources, College of Bioscience and Bioengineering, Jiangxi Agricultural University, Nanchang 330045, China
| | - Congcong Xie
- Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources, College of Bioscience and Bioengineering, Jiangxi Agricultural University, Nanchang 330045, China
| | - Yuting Wan
- Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources, College of Bioscience and Bioengineering, Jiangxi Agricultural University, Nanchang 330045, China
| | - Yating Li
- Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources, College of Bioscience and Bioengineering, Jiangxi Agricultural University, Nanchang 330045, China
| | - Jianping Liu
- Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources, College of Bioscience and Bioengineering, Jiangxi Agricultural University, Nanchang 330045, China
- Collaborative Innovation Center of Postharvest Key Technology and Quality Safety of Fruits and Vegetables in Jiangxi Province, Jiangxi Agricultural University, Nanchang 330045, China
| | - Zhimin Li
- Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources, College of Bioscience and Bioengineering, Jiangxi Agricultural University, Nanchang 330045, China
- Collaborative Innovation Center of Postharvest Key Technology and Quality Safety of Fruits and Vegetables in Jiangxi Province, Jiangxi Agricultural University, Nanchang 330045, China
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30
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Yan Q, Jacobson TB, Ye Z, Cortés-Pena YR, Bhagwat SS, Hubbard S, Cordell WT, Oleniczak RE, Gambacorta FV, Vazquez JR, Shusta EV, Amador-Noguez D, Guest JS, Pfleger BF. Evaluation of 1,2-diacyl-3-acetyl triacylglycerol production in Yarrowia lipolytica. Metab Eng 2023; 76:18-28. [PMID: 36626963 DOI: 10.1016/j.ymben.2023.01.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 12/14/2022] [Accepted: 01/06/2023] [Indexed: 01/09/2023]
Abstract
Plants produce many high-value oleochemical molecules. While oil-crop agriculture is performed at industrial scales, suitable land is not available to meet global oleochemical demand. Worse, establishing new oil-crop farms often comes with the environmental cost of tropical deforestation. The field of metabolic engineering offers tools to transplant oleochemical metabolism into tractable hosts while simultaneously providing access to molecules produced by non-agricultural plants. Here, we evaluate strategies for rewiring metabolism in the oleaginous yeast Yarrowia lipolytica to synthesize a foreign lipid, 3-acetyl-1,2-diacyl-sn-glycerol (acTAG). Oils made up of acTAG have a reduced viscosity and melting point relative to traditional triacylglycerol oils making them attractive as low-grade diesels, lubricants, and emulsifiers. This manuscript describes a metabolic engineering study that established acTAG production at g/L scale, exploration of the impact of lipid bodies on acTAG titer, and a techno-economic analysis that establishes the performance benchmarks required for microbial acTAG production to be economically feasible.
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Affiliation(s)
- Qiang Yan
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI, 53706, USA; DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Tyler B Jacobson
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, USA; DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI, USA; DOE Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN, USA
| | - Zhou Ye
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Yoel R Cortés-Pena
- DOE Center for Advanced Bioenergy and Bioproducts Innovation (CABBI), University of Illinois Urbana-Champaign, 1206 W. Gregory Drive, Urbana, IL, 61801, USA; Department of Civil and Environmental Engineering, University of Illinois Urbana-Champaign, 3221 Newmark Civil Engineering Laboratory, 205 N. Mathews Avenue, Urbana, IL, 61801, USA
| | - Sarang S Bhagwat
- DOE Center for Advanced Bioenergy and Bioproducts Innovation (CABBI), University of Illinois Urbana-Champaign, 1206 W. Gregory Drive, Urbana, IL, 61801, USA; Department of Civil and Environmental Engineering, University of Illinois Urbana-Champaign, 3221 Newmark Civil Engineering Laboratory, 205 N. Mathews Avenue, Urbana, IL, 61801, USA
| | - Susan Hubbard
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI, 53706, USA; DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - William T Cordell
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI, 53706, USA; DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Rebecca E Oleniczak
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI, 53706, USA; DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Francesca V Gambacorta
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI, 53706, USA; DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI, USA
| | - Julio Rivera Vazquez
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, USA; DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI, USA; DOE Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN, USA; Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Eric V Shusta
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI, 53706, USA; Department of Neurological Surgery, University of Wisconsin-Madison, 1415 Engineering Drive, Madison, WI, 53706, USA
| | - Daniel Amador-Noguez
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, USA; DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI, USA; DOE Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN, USA; DOE Center for Advanced Bioenergy and Bioproducts Innovation (CABBI), University of Illinois Urbana-Champaign, 1206 W. Gregory Drive, Urbana, IL, 61801, USA
| | - Jeremy S Guest
- DOE Center for Advanced Bioenergy and Bioproducts Innovation (CABBI), University of Illinois Urbana-Champaign, 1206 W. Gregory Drive, Urbana, IL, 61801, USA; Department of Civil and Environmental Engineering, University of Illinois Urbana-Champaign, 3221 Newmark Civil Engineering Laboratory, 205 N. Mathews Avenue, Urbana, IL, 61801, USA
| | - Brian F Pfleger
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI, 53706, USA; DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Wisconsin-Madison, Madison, WI, 53706, USA; DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI, USA; Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, WI, 53706, USA.
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31
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Mass spectrometry of intact membrane proteins: shifting towards a more native-like context. Essays Biochem 2023; 67:201-213. [PMID: 36807530 PMCID: PMC10070488 DOI: 10.1042/ebc20220169] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 01/20/2023] [Accepted: 01/23/2023] [Indexed: 02/23/2023]
Abstract
Integral membrane proteins are involved in a plethora of biological processes including cellular signalling, molecular transport, and catalysis. Many of these functions are mediated by non-covalent interactions with other proteins, substrates, metabolites, and surrounding lipids. Uncovering such interactions and deciphering their effect on protein activity is essential for understanding the regulatory mechanisms underlying integral membrane protein function. However, the detection of such dynamic complexes has proven to be challenging using traditional approaches in structural biology. Native mass spectrometry has emerged as a powerful technique for the structural characterisation of membrane proteins and their complexes, enabling the detection and identification of protein-binding partners. In this review, we discuss recent native mass spectrometry-based studies that have characterised non-covalent interactions of membrane proteins in the presence of detergents or membrane mimetics. We additionally highlight recent progress towards the study of membrane proteins within native membranes and provide our perspective on how these could be combined with recent developments in instrumentation to investigate increasingly complex biomolecular systems.
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32
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Behera J, Rahman MM, Shockey J, Kilaru A. Acyl-CoA-dependent and acyl-CoA-independent avocado acyltransferases positively influence oleic acid content in nonseed triacylglycerols. FRONTIERS IN PLANT SCIENCE 2023; 13:1056582. [PMID: 36714784 PMCID: PMC9874167 DOI: 10.3389/fpls.2022.1056582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Accepted: 12/15/2022] [Indexed: 06/18/2023]
Abstract
In higher plants, acyl-CoA:diacylglycerol acyltransferase (DGAT) and phospholipid:diacylglycerol acyltransferase (PDAT) catalyze the terminal step of triacylglycerol (TAG) synthesis in acyl-CoA-dependent and -independent pathways, respectively. Avocado (Persea americana) mesocarp, a nonseed tissue, accumulates significant amounts of TAG (~70% by dry weight) that is rich in heart-healthy oleic acid (18:1). The oil accumulation stages of avocado mesocarp development coincide with high expression levels for type-1 DGAT (DGAT1) and PDAT1, although type-2 DGAT (DGAT2) expression remains low. The strong preference for oleic acid demonstrated by the avocado mesocarp TAG biosynthetic machinery represents lucrative biotechnological opportunities, yet functional characterization of these three acyltransferases has not been explored to date. We expressed avocado PaDGAT1, PaDGAT2, and PaPDAT1 in bakers' yeast and leaves of Nicotiana benthamiana. PaDGAT1 complemented the TAG biosynthesis deficiency in the quadruple mutant yeast strain H1246, and substantially elevated total cellular lipid content. In vitro enzyme assays showed that PaDGAT1 prefers oleic acid compared to palmitic acid (16:0). Both PaDGAT1 and PaPDAT1 increased the lipid content and elevated oleic acid levels when expressed independently or together, transiently in N. benthamiana leaves. These results indicate that PaDGAT1 and PaPDAT1 prefer oleate-containing substrates, and their coordinated expression likely contributes to sustained TAG synthesis that is enriched in oleic acid. This study establishes a knowledge base for future metabolic engineering studies focused on exploitation of the biochemical properties of PaDGAT1 and PaPDAT1.
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Affiliation(s)
- Jyoti Behera
- Department of Biological Sciences, East Tennessee State University, Johnson City, TN, United States
| | - Md Mahbubur Rahman
- Department of Biological Sciences, East Tennessee State University, Johnson City, TN, United States
- dNTP Laboratory, Teaneck, NJ, United States
| | - Jay Shockey
- U.S. Department of Agriculture, Agricultural Research Service, Southern Regional Research Center, Commodity Utilization Research Unit, New Orleans, LA, United States
| | - Aruna Kilaru
- Department of Biological Sciences, East Tennessee State University, Johnson City, TN, United States
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33
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Panigrahi R, Glover JNM, Nallusamy S. A look into DGAT1 through the EM lenses. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2023; 1865:184069. [PMID: 36216097 DOI: 10.1016/j.bbamem.2022.184069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Accepted: 10/03/2022] [Indexed: 11/05/2022]
Abstract
With the advent of modern detectors and robust structure solution pipeline, cryogenic electron microscopy has recently proved to be game changer in structural biology. Membrane proteins are challenging targets for structural biologists. This minireview focuses a membrane embedded triglyceride synthesizing machine, DGAT1. Decades of research had built the foundational knowledge on this enzyme's activity. However, recently solved cryo-EM structures of this enzyme, in apo and bound form, has provided critical mechanistic insights. The flipping of the catalytic histidine is critical of enzyme catalysis. The structures explain why the enzyme has preference to long fatty acyl chains over the short forms.
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Affiliation(s)
- Rashmi Panigrahi
- Department of Biochemistry, University of Alberta, Edmonton, Alberta T6G 2H7, Canada.
| | - J N Mark Glover
- Department of Biochemistry, University of Alberta, Edmonton, Alberta T6G 2H7, Canada
| | - Saranya Nallusamy
- Department of Plant Molecular Biology and Bioinformatics, Centre for Plant Molecular Biology and Biotechnology, Tamil Nadu Agricultural University, Coimbatore 641003, India.
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34
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Wu YL, Wu JX, Shen TT, Chai HS, Chen HF, Zhang Q. Quzhi Formula Alleviates Nonalcoholic Steatohepatitis by Impairing Hepatocyte Lipid Accumulation and Inflammation via Bip/eIF2α Signaling. J Clin Transl Hepatol 2022; 10:1050-1058. [PMID: 36381096 PMCID: PMC9634762 DOI: 10.14218/jcth.2021.00458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 12/22/2021] [Accepted: 01/04/2022] [Indexed: 12/04/2022] Open
Abstract
BACKGROUND AND AIMS The Quzhi formula, a Chinese medicine compound prescription, relieves nonalcoholic steatohepatitis (NASH) symptoms. This study aimed to explore the mechanism of the Quzhi formula against NASH. METHODS A choline-deficient, L-amino acid-defined, high-fat diet induced a NASH mouse model and a free fatty acid-induced mouse hepatocyte cell model were used to evaluate the function of Quzhi formula in vivo and in vitro. Network pharmacology and molecular docking technology were performed to uncover the possible protective mechanisms of the Quzhi formula against NASH. Key factors in liver lipid metabolism and endoplasmic reticulum (ER) stress pathway were evaluated to verify the mechanism. RESULTS The positive contribution of the Quzhi formula on NASH was confirmed in vivo and in vitro. Abnormal accumulation of lipid in the liver and inflammatory responses were significantly decreased by the Quzhi formula. Network pharmacological analysis and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis showed that the Quzhi formula protected against NASH by regulating ER stress and inflammatory responses, which was enhanced by further molecular docking analysis. In addition, mechanism exploration showed that Quzhi formula mainly reduced ER stress by downregulating Bip/eIF2α signaling. CONCLUSIONS The Quzhi formula protected against NASH by inhibiting lipid accumulation, ER stress, and inflammatory responses, which supports the potential use of Quzhi formula as an alternative treatment for NASH.
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Affiliation(s)
- Yue-Lan Wu
- Tongren Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jiao-Xiang Wu
- Hongqiao International Institute of Medicine, Tongren Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Department of Clinical Laboratory, Tongren Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Ting-Ting Shen
- Department of Infectious Diseases, Tongren Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Hai-Sheng Chai
- Shanghai municipal Hospital of Traditional Chinese Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Hui-Fen Chen
- Department of Laboratory Medicine, Shanghai First Maternity and Infant Hospital, School of Medicine, Tongji University, Shanghai, China
- Correspondence to: Qin Zhang, Phase I Clinical Trial Unit, Tongren Hospital, Shanghai Jiao Tong University School of Medicine, 1111 XianXia Road, Shanghai 200336, China. ORCID: https://orcid.org/0000-0002-0150-488X. Tel: +86-21-52039999-79305, Fax: +86-21-52039795, E-mail: ; Hui-Fen Chen, Department of Laboratory Medicine, Shanghai First Maternity and Infant Hospital, School of Medicine, Tongji University, 536 ChangLe Road, Shanghai 200040, China. ORCID: https://orcid.org/0000-0002-6630-7035. Tel: +86-21-54033031, Fax: +86-21-50730190, E-mail:
| | - Qin Zhang
- Phase I Clinical Trial Unit, Tongren Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Correspondence to: Qin Zhang, Phase I Clinical Trial Unit, Tongren Hospital, Shanghai Jiao Tong University School of Medicine, 1111 XianXia Road, Shanghai 200336, China. ORCID: https://orcid.org/0000-0002-0150-488X. Tel: +86-21-52039999-79305, Fax: +86-21-52039795, E-mail: ; Hui-Fen Chen, Department of Laboratory Medicine, Shanghai First Maternity and Infant Hospital, School of Medicine, Tongji University, 536 ChangLe Road, Shanghai 200040, China. ORCID: https://orcid.org/0000-0002-6630-7035. Tel: +86-21-54033031, Fax: +86-21-50730190, E-mail:
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Fang X, Zhou Y, Chen S, Xu X, Ke J, Zhou Y, Wei H, Fu B. Natural killer cells promote intra-cellular-infected trophoblasts survival via APOD-LRP1 axis. Immunology 2022. [PMID: 36562137 DOI: 10.1111/imm.13621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Accepted: 12/18/2022] [Indexed: 12/24/2022] Open
Abstract
Natural killer (NK) cells are known for their potent ability to kill stressed cells, whereas host cells infected with intra-cellular bacteria may also be benefit from the selective killing function of NK cells and survive. The mechanism of how NK cells protect host cells infected with intra-cellular bacteria is still unclear. Here, we discovered that decidual NK (dNK) cells cannot only eliminate intra-cellular bacteria which infected trophoblasts, but can also synthesize more lipids and transport lipids to trophoblasts to avoid their apoptosis. Mechanically, NK cells synthesize more lipids accompanied by increasing expression of apolipoprotein APOD. Lipids in NK cells can be delivered to trophoblast cells through APOD, maintaining adequate lipid droplet content and lipid metabolism homeostasis in trophoblasts. Blocking the APOD receptor LRP1 abolished lipid transport from NK cells to trophoblasts, and the reduction of lipid droplets caused by bacterial infection in trophoblast cells could not be restored, culminating in cell apoptosis. Our study provides new evidence for the immune surveillance and protective effect of NK cells on embryos during early pregnancy.
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Affiliation(s)
- Xi Fang
- The CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Basic Medical Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
- Institute of Immunology, University of Science and Technology of China, Hefei, China
| | - Yonggang Zhou
- The CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Basic Medical Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
- Institute of Immunology, University of Science and Technology of China, Hefei, China
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
| | - Siao Chen
- The CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Basic Medical Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
- Institute of Immunology, University of Science and Technology of China, Hefei, China
| | - Xiuxiu Xu
- The CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Basic Medical Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
- Institute of Immunology, University of Science and Technology of China, Hefei, China
| | - Jieqi Ke
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
| | - Ying Zhou
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
| | - Haiming Wei
- The CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Basic Medical Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
- Institute of Immunology, University of Science and Technology of China, Hefei, China
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
| | - Binqing Fu
- The CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Basic Medical Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
- Institute of Immunology, University of Science and Technology of China, Hefei, China
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
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36
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Liang K, Dai JY. Progress of potential drugs targeted in lipid metabolism research. Front Pharmacol 2022; 13:1067652. [PMID: 36588702 PMCID: PMC9800514 DOI: 10.3389/fphar.2022.1067652] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Accepted: 11/28/2022] [Indexed: 12/23/2022] Open
Abstract
Lipids are a class of complex hydrophobic molecules derived from fatty acids that not only form the structural basis of biological membranes but also regulate metabolism and maintain energy balance. The role of lipids in obesity and other metabolic diseases has recently received much attention, making lipid metabolism one of the attractive research areas. Several metabolic diseases are linked to lipid metabolism, including diabetes, obesity, and atherosclerosis. Additionally, lipid metabolism contributes to the rapid growth of cancer cells as abnormal lipid synthesis or uptake enhances the growth of cancer cells. This review introduces the potential drug targets in lipid metabolism and summarizes the important potential drug targets with recent research progress on the corresponding small molecule inhibitor drugs. The significance of this review is to provide a reference for the clinical treatment of metabolic diseases related to lipid metabolism and the treatment of tumors, hoping to deepen the understanding of lipid metabolism and health.
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Affiliation(s)
- Kai Liang
- School of Life Science, Peking University, Beijing, China,*Correspondence: Kai Liang, ; Jian-Ye Dai,
| | - Jian-Ye Dai
- School of Pharmacy, Lanzhou University, Lanzhou, China,Collaborative Innovation Center for Northwestern Chinese Medicine, Lanzhou University, Lanzhou, China,*Correspondence: Kai Liang, ; Jian-Ye Dai,
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The genetics of monogenic intestinal epithelial disorders. Hum Genet 2022; 142:613-654. [PMID: 36422736 PMCID: PMC10182130 DOI: 10.1007/s00439-022-02501-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2022] [Accepted: 10/23/2022] [Indexed: 11/27/2022]
Abstract
Monogenic intestinal epithelial disorders, also known as congenital diarrheas and enteropathies (CoDEs), are a group of rare diseases that result from mutations in genes that primarily affect intestinal epithelial cell function. Patients with CoDE disorders generally present with infantile-onset diarrhea and poor growth, and often require intensive fluid and nutritional management. CoDE disorders can be classified into several categories that relate to broad areas of epithelial function, structure, and development. The advent of accessible and low-cost genetic sequencing has accelerated discovery in the field with over 45 different genes now associated with CoDE disorders. Despite this increasing knowledge in the causal genetics of disease, the underlying cellular pathophysiology remains incompletely understood for many disorders. Consequently, clinical management options for CoDE disorders are currently limited and there is an urgent need for new and disorder-specific therapies. In this review, we provide a general overview of CoDE disorders, including a historical perspective of the field and relationship to other monogenic disorders of the intestine. We describe the genetics, clinical presentation, and known pathophysiology for specific disorders. Lastly, we describe the major challenges relating to CoDE disorders, briefly outline key areas that need further study, and provide a perspective on the future genetic and therapeutic landscape.
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Sim J, Kwon S, Seok C. HProteome-BSite: predicted binding sites and ligands in human 3D proteome. Nucleic Acids Res 2022; 51:D403-D408. [PMID: 36243970 PMCID: PMC9825455 DOI: 10.1093/nar/gkac873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Revised: 09/20/2022] [Accepted: 09/29/2022] [Indexed: 01/29/2023] Open
Abstract
Atomic-level knowledge of protein-ligand interactions allows a detailed understanding of protein functions and provides critical clues to discovering molecules regulating the functions. While recent innovative deep learning methods for protein structure prediction dramatically increased the structural coverage of the human proteome, molecular interactions remain largely unknown. A new database, HProteome-BSite, provides predictions of binding sites and ligands in the enlarged 3D human proteome. The model structures for human proteins from the AlphaFold Protein Structure Database were processed to structural domains of high confidence to maximize the coverage and reliability of interaction prediction. For ligand binding site prediction, an updated version of a template-based method GalaxySite was used. A high-level performance of the updated GalaxySite was confirmed. HProteome-BSite covers 80.74% of the UniProt entries in the AlphaFold human 3D proteome. Predicted binding sites and binding poses of potential ligands are provided for effective applications to further functional studies and drug discovery. The HProteome-BSite database is available at https://galaxy.seoklab.org/hproteome-bsite/database and is free and open to all users.
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Affiliation(s)
- Jiho Sim
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Sohee Kwon
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea,Galux Inc, Gwanak-gu, Seoul 08738, Republic of Korea
| | - Chaok Seok
- To whom correspondence should be addressed. Tel: +82 2 880 9197; Fax: +82 2 889 1568;
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Applications of human organoids in the personalized treatment for digestive diseases. Signal Transduct Target Ther 2022; 7:336. [PMID: 36167824 PMCID: PMC9513303 DOI: 10.1038/s41392-022-01194-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 08/09/2022] [Accepted: 09/13/2022] [Indexed: 11/15/2022] Open
Abstract
Digestive system diseases arise primarily through the interplay of genetic and environmental influences; there is an urgent need in elucidating the pathogenic mechanisms of these diseases and deploy personalized treatments. Traditional and long-established model systems rarely reproduce either tissue complexity or human physiology faithfully; these shortcomings underscore the need for better models. Organoids represent a promising research model, helping us gain a more profound understanding of the digestive organs; this model can also be used to provide patients with precise and individualized treatment and to build rapid in vitro test models for drug screening or gene/cell therapy, linking basic research with clinical treatment. Over the past few decades, the use of organoids has led to an advanced understanding of the composition of each digestive organ and has facilitated disease modeling, chemotherapy dose prediction, CRISPR-Cas9 genetic intervention, high-throughput drug screening, and identification of SARS-CoV-2 targets, pathogenic infection. However, the existing organoids of the digestive system mainly include the epithelial system. In order to reveal the pathogenic mechanism of digestive diseases, it is necessary to establish a completer and more physiological organoid model. Combining organoids and advanced techniques to test individualized treatments of different formulations is a promising approach that requires further exploration. This review highlights the advancements in the field of organoid technology from the perspectives of disease modeling and personalized therapy.
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Li Q, Li R, Yin H, Wang S, Liu B, Li J, Zhou M, Yan Q, Lu L. Oral IRAK4 inhibitor BAY-1834845 prevents acute respiratory distress syndrome. Biomed Pharmacother 2022; 153:113459. [PMID: 36076574 PMCID: PMC9339262 DOI: 10.1016/j.biopha.2022.113459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2022] [Revised: 07/14/2022] [Accepted: 07/21/2022] [Indexed: 02/04/2023] Open
Abstract
Acute respiratory distress syndrome (ARDS) is a lethal clinical entity that has become an emergency event with the outbreak of COVID-19. However, to date, there are no well-proven pharmacotherapies except dexamethasone. This study is aimed to evaluate IRAK4 inhibitors as a potential treatment for ARDS-cytokine release syndrome (CRS). We applied two IRAK4 inhibitors, BAY-1834845 and PF-06650833 to an inhaled lipopolysaccharide (LPS)-induced ARDS mouse model with control of high dose dexamethasone (10 mg/kg). Unexpectedly, although both compounds had excellent IC50 on IRAK4 kinase activity, only BAY-1834845 but not PF-06650833 or high dose dexamethasone could significantly prevent lung injury according to a blinded pathology scoring. Further, only BAY-1834845 and BAY-1834845 combined with dexamethasone could effectively improve the injury score of pre-existed ARDS. Compared with PF-06650833 and high dose dexamethasone, BAY-1834845 remarkably decreased inflammatory cells infiltrating lung tissue and neutrophil count in BALF. BAY-1834845, DEX, and the combination of the two agents could decrease BALF total T cells, monocyte, and macrophages. In further cell type enrichment analysis based on lung tissue RNA-seq, both BAY-1834845 and dexamethasone decreased signatures of inflammatory cells and effector lymphocytes. Interestingly, unlike the dexamethasone group, BAY-1834845 largely preserved the signatures of naïve lymphocytes and stromal cells such as endothelial cells, chondrocytes, and smooth muscle cells. Differential gene enrichment suggested that BAY-1834845 downregulated genes more efficiently than dexamethasone, especially TNF, IL-17, interferon, and Toll-like receptor signaling.
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41
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Schonbrun AR, Resh MD. Hedgehog acyltransferase catalyzes a random sequential reaction and utilizes multiple fatty acyl-CoA substrates. J Biol Chem 2022; 298:102422. [PMID: 36030053 PMCID: PMC9513256 DOI: 10.1016/j.jbc.2022.102422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 08/17/2022] [Accepted: 08/19/2022] [Indexed: 11/17/2022] Open
Abstract
Sonic hedgehog (Shh) signaling is a key component of embryonic development and is a driving force in several cancers. Hedgehog acyltransferase (Hhat), a member of the membrane-bound O-acyltransferase family of enzymes, catalyzes the attachment of palmitate to the N-terminal cysteine of Shh, a posttranslation modification critical for Shh signaling. The activity of Hhat has been assayed in cells and in vitro, and cryo-EM structures of Hhat have been reported, yet several unanswered questions remain regarding the enzyme’s reaction mechanism, substrate specificity, and the impact of the latter on Shh signaling. Here, we present an in vitro acylation assay with purified Hhat that directly monitors attachment of a fluorescently tagged fatty acyl chain to Shh. Our kinetic analyses revealed that the reaction catalyzed by Hhat proceeds through a random sequential mechanism. We also determined that Hhat can utilize multiple fatty acyl-CoA substrates for fatty acid transfer to Shh, with comparable affinities and turnover rates for myristoyl-CoA, palmitoyl-CoA, palmitoleoyl-CoA, and oleoyl-CoA. Furthermore, we investigated the functional consequence of differential fatty acylation of Shh in a luciferase-based Shh reporter system. We found that the potency of the signaling response in cells was higher for Shh acylated with saturated fatty acids compared to monounsaturated fatty acids. These findings demonstrate that Hhat can attach fatty acids other than palmitate to Shh and suggest that heterogeneous fatty acylation has the potential to impact Shh signaling in the developing embryo and/or cancer cells.
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Affiliation(s)
- Adina R Schonbrun
- Cell Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY; Gerstner Sloan Kettering Graduate School
| | - Marilyn D Resh
- Cell Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY; Gerstner Sloan Kettering Graduate School; Biochemistry, Cell Biology and Molecular Biology Graduate Program, Weill-Cornell Graduate School of Medical Sciences, New York, NY.
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Kou Y, Geng F, Guo D. Lipid Metabolism in Glioblastoma: From De Novo Synthesis to Storage. Biomedicines 2022; 10:1943. [PMID: 36009491 PMCID: PMC9405736 DOI: 10.3390/biomedicines10081943] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 08/01/2022] [Accepted: 08/06/2022] [Indexed: 12/12/2022] Open
Abstract
Glioblastoma (GBM) is the most lethal primary brain tumor. With limited therapeutic options, novel therapies are desperately needed. Recent studies have shown that GBM acquires large amounts of lipids for rapid growth through activation of sterol regulatory element-binding protein 1 (SREBP-1), a master transcription factor that regulates fatty acid and cholesterol synthesis, and cholesterol uptake. Interestingly, GBM cells divert substantial quantities of lipids into lipid droplets (LDs), a specific storage organelle for neutral lipids, to prevent lipotoxicity by increasing the expression of diacylglycerol acyltransferase 1 (DGAT1) and sterol-O-acyltransferase 1 (SOAT1), which convert excess fatty acids and cholesterol to triacylglycerol and cholesteryl esters, respectively. In this review, we will summarize recent progress on our understanding of lipid metabolism regulation in GBM to promote tumor growth and discuss novel strategies to specifically induce lipotoxicity to tumor cells through disrupting lipid storage, a promising new avenue for treating GBM.
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Affiliation(s)
- Yongjun Kou
- Department of Radiation Oncology, Ohio State Comprehensive Cancer Center, Arthur G. James Cancer Hospital and Richard J. Solove Research Institute, College of Medicine at The Ohio State University, Columbus, OH 43012, USA
| | - Feng Geng
- Department of Radiation Oncology, Ohio State Comprehensive Cancer Center, Arthur G. James Cancer Hospital and Richard J. Solove Research Institute, College of Medicine at The Ohio State University, Columbus, OH 43012, USA
| | - Deliang Guo
- Department of Radiation Oncology, Ohio State Comprehensive Cancer Center, Arthur G. James Cancer Hospital and Richard J. Solove Research Institute, College of Medicine at The Ohio State University, Columbus, OH 43012, USA
- Center for Cancer Metabolism, James Comprehensive Cancer Center at The Ohio State University, Columbus, OH 43210, USA
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43
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Mechanisms and inhibition of Porcupine-mediated Wnt acylation. Nature 2022; 607:816-822. [PMID: 35831507 DOI: 10.1038/s41586-022-04952-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2022] [Accepted: 06/08/2022] [Indexed: 12/14/2022]
Abstract
Wnt signalling is essential for regulation of embryonic development and adult tissue homeostasis1-3, and aberrant Wnt signalling is frequently associated with cancers4. Wnt signalling requires palmitoleoylation on a hairpin 2 motif by the endoplasmic reticulum-resident membrane-bound O-acyltransferase Porcupine5-7 (PORCN). This modification is indispensable for Wnt binding to its receptor Frizzled, which triggers signalling8,9. Here we report four cryo-electron microscopy structures of human PORCN: the complex with the palmitoleoyl-coenzyme A (palmitoleoyl-CoA) substrate; the complex with the PORCN inhibitor LGK974, an anti-cancer drug currently in clinical trials10; the complex with LGK974 and WNT3A hairpin 2 (WNT3Ap); and the complex with a synthetic palmitoleoylated WNT3Ap analogue. The structures reveal that hairpin 2 of WNT3A, which is well conserved in all Wnt ligands, inserts into PORCN from the lumenal side, and the palmitoleoyl-CoA accesses the enzyme from the cytosolic side. The catalytic histidine triggers the transfer of the unsaturated palmitoleoyl group to the target serine on the Wnt hairpin 2, facilitated by the proximity of the two substrates. The inhibitor-bound structure shows that LGK974 occupies the palmitoleoyl-CoA binding site to prevent the reaction. Thus, this work provides a mechanism for Wnt acylation and advances the development of PORCN inhibitors for cancer treatment.
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Chen G, Harwood JL, Lemieux MJ, Stone SJ, Weselake RJ. Acyl-CoA:diacylglycerol acyltransferase: Properties, physiological roles, metabolic engineering and intentional control. Prog Lipid Res 2022; 88:101181. [PMID: 35820474 DOI: 10.1016/j.plipres.2022.101181] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 05/31/2022] [Accepted: 07/04/2022] [Indexed: 12/15/2022]
Abstract
Acyl-CoA:diacylglycerol acyltransferase (DGAT, EC 2.3.1.20) catalyzes the last reaction in the acyl-CoA-dependent biosynthesis of triacylglycerol (TAG). DGAT activity resides mainly in membrane-bound DGAT1 and DGAT2 in eukaryotes and bifunctional wax ester synthase-diacylglycerol acyltransferase (WSD) in bacteria, which are all membrane-bound proteins but exhibit no sequence homology to each other. Recent studies also identified other DGAT enzymes such as the soluble DGAT3 and diacylglycerol acetyltransferase (EaDAcT), as well as enzymes with DGAT activities including defective in cuticular ridges (DCR) and steryl and phytyl ester synthases (PESs). This review comprehensively discusses research advances on DGATs in prokaryotes and eukaryotes with a focus on their biochemical properties, physiological roles, and biotechnological and therapeutic applications. The review begins with a discussion of DGAT assay methods, followed by a systematic discussion of TAG biosynthesis and the properties and physiological role of DGATs. Thereafter, the review discusses the three-dimensional structure and insights into mechanism of action of human DGAT1, and the modeled DGAT1 from Brassica napus. The review then examines metabolic engineering strategies involving manipulation of DGAT, followed by a discussion of its therapeutic applications. DGAT in relation to improvement of livestock traits is also discussed along with DGATs in various other eukaryotic organisms.
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Affiliation(s)
- Guanqun Chen
- Department of Agricultural, Food, and Nutritional Science, University of Alberta, Edmonton, Alberta T6H 2P5, Canada.
| | - John L Harwood
- School of Biosciences, Cardiff University, Cardiff CF10 3AX, UK
| | - M Joanne Lemieux
- Department of Biochemistry, University of Alberta, Membrane Protein Disease Research Group, Edmonton T6G 2H7, Canada
| | - Scot J Stone
- Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E5, Canada.
| | - Randall J Weselake
- Department of Agricultural, Food, and Nutritional Science, University of Alberta, Edmonton, Alberta T6H 2P5, Canada
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Hatanaka T, Tomita Y, Matsuoka D, Sasayama D, Fukayama H, Azuma T, Soltani Gishini MF, Hildebrand D. Different acyl-CoA:diacylglycerol acyltransferases vary widely in function, and a targeted amino acid substitution enhances oil accumulation. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:3030-3043. [PMID: 35560190 DOI: 10.1093/jxb/erac084] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Accepted: 03/02/2022] [Indexed: 06/15/2023]
Abstract
Triacylglycerols (TAGs) are the major component of plant storage lipids such as oils. Acyl-CoA:diacylglycerol acyltransferase (DGAT) catalyzes the final step of the Kennedy pathway, and is mainly responsible for plant oil accumulation. We previously found that the activity of Vernonia DGAT1 was distinctively higher than that of Arabidopsis and soybean DGAT1 in a yeast microsome assay. In this study, the DGAT1 cDNAs of Arabidopsis, Vernonia, soybean, and castor bean were introduced into Arabidopsis. All Vernonia DGAT1-expressing lines showed a significantly higher oil content (49% mean increase compared with the wild-type) followed by soybean and castor bean. Most Arabidopsis DGAT1-overexpressing lines did not show a significant increase. In addition to these four DGAT1 genes, sunflower, Jatropha, and sesame DGAT1 genes were introduced into a TAG biosynthesis-defective yeast mutant. In the yeast expression culture, DGAT1s from Arabidopsis, castor bean, and soybean only slightly increased the TAG content; however, DGAT1s from Vernonia, sunflower, Jatropha, and sesame increased TAG content >10-fold more than the former three DGAT1s. Three amino acid residues were characteristically common in the latter four DGAT1s. Using soybean DGAT1, these amino acid substitutions were created by site-directed mutagenesis and substantially increased the TAG content.
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Affiliation(s)
- Tomoko Hatanaka
- Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo, Japan
| | - Yoshiki Tomita
- Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo, Japan
| | - Daisuke Matsuoka
- Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo, Japan
| | - Daisuke Sasayama
- Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo, Japan
| | - Hiroshi Fukayama
- Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo, Japan
| | - Tetsushi Azuma
- Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo, Japan
| | - Mohammad Fazel Soltani Gishini
- Department of Production Engineering and Plant Genetics, Faculty of Sciences and Agricultural Engineering, Campus of Agriculture and Natural Resources, Razi University, Kermanshah, Iran
| | - David Hildebrand
- Department of Plant and Soil Sciences, University of Kentucky, Lexington, KY, USA
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Stone SJ. Mechanisms of intestinal triacylglycerol synthesis. Biochim Biophys Acta Mol Cell Biol Lipids 2022; 1867:159151. [PMID: 35296424 DOI: 10.1016/j.bbalip.2022.159151] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 01/13/2022] [Accepted: 02/16/2022] [Indexed: 02/07/2023]
Abstract
Triacylglycerols are a major source of stored energy that are obtained either from the diet or can be synthesized to some extent by most tissues. Alterations in pathways of triacylglycerol metabolism can result in their excessive accumulation leading to obesity, insulin resistance, cardiovascular disease and nonalcoholic fatty liver disease. Most tissues in mammals synthesize triacylglycerols via the glycerol 3-phosphate pathway. However, in the small intestine the monoacylglycerol acyltransferase pathway is the predominant pathway for triacylglycerol biosynthesis where it participates in the absorption of dietary triacylglycerol. In this review, the enzymes that are part of both the glycerol 3-phosphate and monoacylglycerol acyltransferase pathways and their contributions to intestinal triacylglycerol metabolism are reviewed. The potential of some of the enzymes involved in triacylglycerol synthesis in the small intestine as possible therapeutic targets for treating metabolic disorders associated with elevated triacylglycerol is briefly discussed.
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Affiliation(s)
- Scot J Stone
- Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E5, Canada.
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Abstract
Cryogenic electron microscopy (cryo-EM) has revolutionized the field of structural biology, particularly in solving the structures of large protein complexes or cellular machineries that play important biological functions. This review focuses on the contribution and future potential of cryo-EM in related emerging applications-enzymatic mechanisms and dynamic processes. Work on these subjects can benefit greatly from the capability of cryo-EM to solve the structures of specific protein complexes in multiple conditions, including variations in the buffer condition, ligands, and temperature, and to capture multiple conformational states, conformational change intermediates, and reaction intermediates. These studies can expand the structural landscape of specific proteins or protein complexes in multiple dimensions and drive new advances in the fields of enzymology and dynamic processes. The advantages and complementarity of cryo-EM relative to X-ray crystallography and nuclear magnetic resonance with regard to these applications are also addressed. Expected final online publication date for the Annual Review of Biophysics, Volume 51 is May 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Ming-Daw Tsai
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan; .,Institute of Biochemical Sciences, National Taiwan University, Taipei, Taiwan
| | - Wen-Jin Wu
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan;
| | - Meng-Chiao Ho
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan; .,Institute of Biochemical Sciences, National Taiwan University, Taipei, Taiwan
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Coupland CE, Andrei SA, Ansell TB, Carrique L, Kumar P, Sefer L, Schwab RA, Byrne EFX, Pardon E, Steyaert J, Magee AI, Lanyon-Hogg T, Sansom MSP, Tate EW, Siebold C. Structure, mechanism, and inhibition of Hedgehog acyltransferase. Mol Cell 2021; 81:5025-5038.e10. [PMID: 34890564 PMCID: PMC8693861 DOI: 10.1016/j.molcel.2021.11.018] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 09/27/2021] [Accepted: 11/17/2021] [Indexed: 01/20/2023]
Abstract
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.
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Affiliation(s)
- Claire E Coupland
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Sebastian A Andrei
- Department of Chemistry, Imperial College London, 82 Wood Lane, London W12 0BZ, UK
| | - T Bertie Ansell
- Department of Biochemistry, University of Oxford, University of Oxford, South Parks Road, Oxford OX1 3QU, UK
| | - Loic Carrique
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Pramod Kumar
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Lea Sefer
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Rebekka A Schwab
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Eamon F X Byrne
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Els Pardon
- Structural Biology Brussels, Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium; VIB-VUB Center for Structural Biology, Vlaams Instituut Biotechnologie (VIB), Pleinlaan 2, 1050 Brussels, Belgium
| | - Jan Steyaert
- Structural Biology Brussels, Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium; VIB-VUB Center for Structural Biology, Vlaams Instituut Biotechnologie (VIB), Pleinlaan 2, 1050 Brussels, Belgium
| | - Anthony I Magee
- National Heart and Lung Institute, Imperial College London, Exhibition Road, London SW7 2AZ, UK
| | - Thomas Lanyon-Hogg
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, UK
| | - Mark S P Sansom
- Department of Biochemistry, University of Oxford, University of Oxford, South Parks Road, Oxford OX1 3QU, UK
| | - Edward W Tate
- Department of Chemistry, Imperial College London, 82 Wood Lane, London W12 0BZ, UK.
| | - Christian Siebold
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK.
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Yu J, Liao PJ, Xu W, Jones JR, Everman DB, Flanagan-Steet H, Keller TH, Virshup DM. Structural model of human PORCN illuminates disease-associated variants and drug-binding sites. J Cell Sci 2021; 134:273795. [PMID: 34817055 DOI: 10.1242/jcs.259383] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 11/11/2021] [Indexed: 12/20/2022] Open
Abstract
Wnt signaling is essential for normal development and is a therapeutic target in cancer. The enzyme PORCN, or porcupine, is a membrane-bound O-acyltransferase (MBOAT) that is required for the post-translational modification of all Wnts, adding an essential mono-unsaturated palmitoleic acid to a serine on the tip of Wnt hairpin 2. Inherited mutations in PORCN cause focal dermal hypoplasia, and therapeutic inhibition of PORCN slows the growth of Wnt-dependent cancers. Based on homology to mammalian MBOAT proteins, we developed and validated a structural model of human PORCN. The model accommodates palmitoleoyl-CoA and Wnt hairpin 2 in two tunnels in the conserved catalytic core, shedding light on the catalytic mechanism. The model predicts how previously uncharacterized human variants of uncertain significance can alter PORCN function. Drugs including ETC-159, IWP-L6 and LGK-974 dock in the PORCN catalytic site, providing insights into PORCN pharmacologic inhibition. This structural model enhances our mechanistic understanding of PORCN substrate recognition and catalysis, as well as the inhibition of its enzymatic activity, and can facilitate the development of improved inhibitors and the understanding of disease-relevant PORCN mutants. This article has an associated First Person interview with the joint first authors of the paper.
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Affiliation(s)
- Jia Yu
- Programme in Cancer and Stem Cell Biology, Duke-NUS Medical School, 169857, Singapore
| | - Pei-Ju Liao
- Programme in Cancer and Stem Cell Biology, Duke-NUS Medical School, 169857, Singapore
| | - Weijun Xu
- Discovery Chemistry, Experimental Drug Development Centre, 10 Biopolis Road, Chromos, 138670, Singapore
| | - Julie R Jones
- JC Self Research Institute, Greenwood Genetic Center, Greenwood, SC 29646, USA
| | - David B Everman
- JC Self Research Institute, Greenwood Genetic Center, Greenwood, SC 29646, USA
| | | | - Thomas H Keller
- Discovery Chemistry, Experimental Drug Development Centre, 10 Biopolis Road, Chromos, 138670, Singapore
| | - David M Virshup
- Programme in Cancer and Stem Cell Biology, Duke-NUS Medical School, 169857, Singapore.,Department of Pediatrics, Duke University School of Medicine, Durham, NC 27710, USA
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Valentine WJ, Yanagida K, Kawana H, Kono N, Noda NN, Aoki J, Shindou H. Update and nomenclature proposal for mammalian lysophospholipid acyltransferases which create membrane phospholipid diversity. J Biol Chem 2021; 298:101470. [PMID: 34890643 PMCID: PMC8753187 DOI: 10.1016/j.jbc.2021.101470] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Accepted: 11/23/2021] [Indexed: 12/13/2022] Open
Abstract
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 A1/2s 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.
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Affiliation(s)
- William J Valentine
- Department of Lipid Signaling, National Center for Global Health and Medicine (NCGM), Shinjuku-ku, Tokyo 162-8655, Japan; Department of Molecular Therapy, National Institute of Neuroscience, National Center of Neurology and Psychiatry (NCNP), Kodaira, Tokyo, 187-8502, Japan
| | - Keisuke Yanagida
- Department of Lipid Signaling, National Center for Global Health and Medicine (NCGM), Shinjuku-ku, Tokyo 162-8655, Japan
| | - Hiroki Kawana
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Nozomu Kono
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Nobuo N Noda
- Institute of Microbial Chemistry (BIKAKEN), Microbial Chemistry Research Foundation, Tokyo 141-0021, Japan
| | - Junken Aoki
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Hideo Shindou
- Department of Lipid Signaling, National Center for Global Health and Medicine (NCGM), Shinjuku-ku, Tokyo 162-8655, Japan; Department of Lipid Medical Science, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan.
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