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Horváth G, Balterer B, Micsonai A, Kardos J, Toke O. Multiple Timescale Dynamic Analysis of Functionally-Impairing Mutations in Human Ileal Bile Acid-Binding Protein. Int J Mol Sci 2022; 23:ijms231911346. [PMID: 36232642 PMCID: PMC9569817 DOI: 10.3390/ijms231911346] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 09/16/2022] [Accepted: 09/20/2022] [Indexed: 11/16/2022] Open
Abstract
Human ileal bile acid-binding protein (hI-BABP) has a key role in the enterohepatic circulation of bile salts. Its two internal binding sites exhibit positive cooperativity accompanied by a site-selectivity of glycocholate (GCA) and glycochenodeoxycholate (GCDA), the two most abundant bile salts in humans. To improve our understanding of the role of dynamics in ligand binding, we introduced functionally impairing single-residue mutations at two key regions of the protein and subjected the mutants to NMR relaxation analysis and MD simulations. According to our results, mutation in both the vicinity of the C/D (Q51A) and the G/H (Q99A) turns results in a redistribution of motional freedom in apo hI-BABP. Mutation Q51A, deteriorating the site-selectivity of GCA and GCDA, results in the channeling of ms fluctuations into faster motions in the binding pocket hampering the realization of key side chain interactions. Mutation Q99A, abolishing positive binding cooperativity for GCDA, leaves ms motions in the C-terminal half unchanged but by decoupling βD from a dynamic cluster of the N-terminal half displays an increased flexibility in the vicinity of site 1. MD simulations of the variants indicate structural differences in the portal region and mutation-induced changes in dynamics, which depend on the protonation state of histidines. A dynamic coupling between the EFGH portal, the C/D-region, and the helical cap is evidenced highlighting the interplay of structural and dynamic effects in bile salt recognition in hI-BABP.
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Affiliation(s)
- Gergő Horváth
- NMR Research Laboratory, Centre for Structural Science, Research Centre for Natural Sciences, 2 Magyar Tudósok Körútja, H-1117 Budapest, Hungary
| | - Bence Balterer
- NMR Research Laboratory, Centre for Structural Science, Research Centre for Natural Sciences, 2 Magyar Tudósok Körútja, H-1117 Budapest, Hungary
| | - András Micsonai
- ELTE NAP Neuroimmunology Research Group, Department of Biochemistry, Institute of Biology, ELTE Eötvös Loránd University, Pázmány Péter sétány 1/C, H-1117 Budapest, Hungary
| | - József Kardos
- ELTE NAP Neuroimmunology Research Group, Department of Biochemistry, Institute of Biology, ELTE Eötvös Loránd University, Pázmány Péter sétány 1/C, H-1117 Budapest, Hungary
| | - Orsolya Toke
- NMR Research Laboratory, Centre for Structural Science, Research Centre for Natural Sciences, 2 Magyar Tudósok Körútja, H-1117 Budapest, Hungary
- Correspondence: ; Tel.: +36-1-382-6575
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Wang L, Liu Q, Hu X, Zhou C, Ma Y, Wang X, Tang Y, Chen K, Wang X, Liu Y. Enhanced Oral Absorption and Liver Distribution of Polymeric Nanoparticles through Traveling the Enterohepatic Circulation Pathways of Bile Acid. ACS APPLIED MATERIALS & INTERFACES 2022; 14:41712-41725. [PMID: 36069201 DOI: 10.1021/acsami.2c10322] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The intestinal epithelium is known to be a main hindrance to oral delivery of nanoparticles. Even though surface ligand modification can enhance cellular uptake of nanoparticles, the "easy entry and hard across" was frequently observed for many active targeting nanoparticles. Here, we fabricated polymeric nanoparticles relayed by bile acid transporters with monomethoxy poly(ethylene glycol)-poly(D,l-lactide) and deoxycholic acid-conjugated poly(2-ethyl-2-oxazoline)-poly(D,l-lactide) based on structural characteristics of intestine epithelium and the absorption characteristics of endogenous substances. As anticipated, deoxycholic acid-modified polymeric nanoparticles featuring good stability in simulated gastrointestinal fluid could notably promote the internalization of their payload by Caco-2 cells through mediation of apical sodium-dependent bile acid transporter (ASBT) and transmembrane transport of the nanoparticles across Caco-2 cell monolayers via relay-guide of ASBT, ileal bile acid-binding protein, and the heteromeric organic solute transporter (OSTα-OSTβ) along with multidrug resistance-associated protein 3 (MRP3) evidenced by competitive inhibition and fluorescence immunoassay, which was further visually confirmed by the stronger fluorescence from C6-labeled nanoparticles inside enterocytes and the basal side of the intestinal epithelium of mice. The transcellular transport of deoxycholic acid-modified nanoparticles in an intact form was mediated by caveolin/lipid rafts and clathrin with intracellular trafficking trace of endosome-lysosome-ER-Golgi apparatus and bile acid transport route. Furthermore, the increased uptake by HepG2 cells compared with unmodified nanoparticles evidenced the target ability of deoxycholic acid-modified nanoparticles to the liver, which was further supported by ex vivo imaging of excised major organs of mice. Thus, this study provided a feasible and potential strategy to further enhance transepithelial transport efficiency and liver-targeted ability of nanoparticles by means of the specific enterohepatic circulation pathways of bile acid.
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Affiliation(s)
- Leqi Wang
- Beijing Key Laboratory of Molecular Pharmaceutics and New Drug Delivery Systems, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
| | - Qi Liu
- Beijing Key Laboratory of Molecular Pharmaceutics and New Drug Delivery Systems, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
| | - Xinping Hu
- Beijing Key Laboratory of Molecular Pharmaceutics and New Drug Delivery Systems, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
| | - Chuhang Zhou
- Beijing Key Laboratory of Molecular Pharmaceutics and New Drug Delivery Systems, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
| | - Yining Ma
- Beijing Key Laboratory of Molecular Pharmaceutics and New Drug Delivery Systems, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
| | - Xiaoxiao Wang
- Beijing Key Laboratory of Molecular Pharmaceutics and New Drug Delivery Systems, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
| | - Yingwei Tang
- Beijing Key Laboratory of Molecular Pharmaceutics and New Drug Delivery Systems, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
| | - Kanghao Chen
- Beijing Key Laboratory of Molecular Pharmaceutics and New Drug Delivery Systems, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
| | - Xinyu Wang
- Beijing Key Laboratory of Molecular Pharmaceutics and New Drug Delivery Systems, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
| | - Yan Liu
- Beijing Key Laboratory of Molecular Pharmaceutics and New Drug Delivery Systems, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
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3
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Toke O. Structural and Dynamic Determinants of Molecular Recognition in Bile Acid-Binding Proteins. Int J Mol Sci 2022; 23:ijms23010505. [PMID: 35008930 PMCID: PMC8745080 DOI: 10.3390/ijms23010505] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 12/30/2021] [Accepted: 12/31/2021] [Indexed: 12/12/2022] Open
Abstract
Disorders in bile acid transport and metabolism have been related to a number of metabolic disease states, atherosclerosis, type-II diabetes, and cancer. Bile acid-binding proteins (BABPs), a subfamily of intracellular lipid-binding proteins (iLBPs), have a key role in the cellular trafficking and metabolic targeting of bile salts. Within the family of iLBPs, BABPs exhibit unique binding properties including positive binding cooperativity and site-selectivity, which in different tissues and organisms appears to be tailored to the local bile salt pool. Structural and biophysical studies of the past two decades have shed light on the mechanism of bile salt binding at the atomic level, providing us with a mechanistic picture of ligand entry and release, and the communication between the binding sites. In this review, we discuss the emerging view of bile salt recognition in intestinal- and liver-BABPs, with examples from both mammalian and non-mammalian species. The structural and dynamic determinants of the BABP-bile–salt interaction reviewed herein set the basis for the design and development of drug candidates targeting the transcellular traffic of bile salts in enterocytes and hepatocytes.
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Affiliation(s)
- Orsolya Toke
- Laboratory for NMR Spectroscopy, Structural Research Centre, Research Centre for Natural Sciences, 2 Magyar Tudósok Körútja, H-1117 Budapest, Hungary
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4
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Ticho AL, Malhotra P, Dudeja PK, Gill RK, Alrefai WA. Intestinal Absorption of Bile Acids in Health and Disease. Compr Physiol 2019; 10:21-56. [PMID: 31853951 PMCID: PMC7171925 DOI: 10.1002/cphy.c190007] [Citation(s) in RCA: 109] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The intestinal reclamation of bile acids is crucial for the maintenance of their enterohepatic circulation. The majority of bile acids are actively absorbed via specific transport proteins that are highly expressed in the distal ileum. The uptake of bile acids by intestinal epithelial cells modulates the activation of cytosolic and membrane receptors such as the farnesoid X receptor (FXR) and G protein-coupled bile acid receptor 1 (GPBAR1), which has a profound effect on hepatic synthesis of bile acids as well as glucose and lipid metabolism. Extensive research has focused on delineating the processes of bile acid absorption and determining the contribution of dysregulated ileal signaling in the development of intestinal and hepatic disorders. For example, a decrease in the levels of the bile acid-induced ileal hormone FGF15/19 is implicated in bile acid-induced diarrhea (BAD). Conversely, the increase in bile acid absorption with subsequent overload of bile acids could be involved in the pathophysiology of liver and metabolic disorders such as fatty liver diseases and type 2 diabetes mellitus. This review article will attempt to provide a comprehensive overview of the mechanisms involved in the intestinal handling of bile acids, the pathological implications of disrupted intestinal bile acid homeostasis, and the potential therapeutic targets for the treatment of bile acid-related disorders. Published 2020. Compr Physiol 10:21-56, 2020.
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Affiliation(s)
- Alexander L. Ticho
- Department of Physiology and Biophysics, College of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Pooja Malhotra
- Division of Gastroenterology & Hepatology, Department of Medicine, College of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Pradeep K. Dudeja
- Division of Gastroenterology & Hepatology, Department of Medicine, College of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA
- jesse Brown VA Medical Center, Chicago, Illinois, USA
| | - Ravinder K. Gill
- Division of Gastroenterology & Hepatology, Department of Medicine, College of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Waddah A. Alrefai
- Division of Gastroenterology & Hepatology, Department of Medicine, College of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA
- jesse Brown VA Medical Center, Chicago, Illinois, USA
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5
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Li S, Hua D, Wang Q, Yang L, Wang X, Luo A, Yang C. The Role of Bacteria and Its Derived Metabolites in Chronic Pain and Depression: Recent Findings and Research Progress. Int J Neuropsychopharmacol 2019; 23:26-41. [PMID: 31760425 PMCID: PMC7064053 DOI: 10.1093/ijnp/pyz061] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Revised: 10/30/2019] [Accepted: 11/22/2019] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Chronic pain is frequently comorbid with depression in clinical practice. Recently, alterations in gut microbiota and metabolites derived therefrom have been found to potentially contribute to abnormal behaviors and cognitive dysfunction via the "microbiota-gut-brain" axis. METHODS PubMed was searched and we selected relevant studies before October 1, 2019. The search keyword string included "pain OR chronic pain" AND "gut microbiota OR metabolites"; "depression OR depressive disorder" AND "gut microbiota OR metabolites". We also searched the reference lists of key articles manually. RESULTS This review systematically summarized the recent evidence of gut microbiota and metabolites in chronic pain and depression in animal and human studies. The results showed the pathogenesis and therapeutics of chronic pain and depression might be partially due to gut microbiota dysbiosis. Importantly, bacteria-derived metabolites, including short-chain fatty acids, tryptophan-derived metabolites, and secondary bile acids, offer new insights into the potential linkage between key triggers in gut microbiota and potential mechanisms of depression. CONCLUSION Studying gut microbiota and its metabolites has contributed to the understanding of comorbidity of chronic pain and depression. Consequently, modulating dietary structures or supplementation of specific bacteria may be an available strategy for treating chronic pain and depression.
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Affiliation(s)
- Shan Li
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Dongyu Hua
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Qiaoyan Wang
- Department of Anesthesiology, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
| | - Ling Yang
- Department of Cardiology, The Third Affiliated Hospital of Soochow University, Changzhou, China
| | - Xinlei Wang
- Department of Anesthesiology, The First Affiliated Hospital of Nanchang University, Nanchang, China
| | - Ailin Luo
- Department of Anesthesiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Chun Yang
- Department of Anesthesiology and Perioperative Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China,Correspondence: Chun Yang, MD, PhD, Department of Anesthesiology and Perioperative Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China (; )
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6
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McKillop IH, Girardi CA, Thompson KJ. Role of fatty acid binding proteins (FABPs) in cancer development and progression. Cell Signal 2019; 62:109336. [PMID: 31170472 DOI: 10.1016/j.cellsig.2019.06.001] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 05/31/2019] [Accepted: 06/01/2019] [Indexed: 01/06/2023]
Abstract
Fatty acid binding proteins (FABPs) are small, water soluble proteins that bind long chain fatty acids and other biologically active ligands to facilitate intracellular localization. Twelve FABP family members have been identified to date, with 10 isoforms expressed in humans. Functionally, FABPs are important in fatty acid metabolism and transport, with distinct family members having the capacity to influence gene transcription. Expression of FABPs is usually cell/tissue specific to one predominant FABP family member. Dysregulation of FABP expression can occur through genetic mutation and/or environmental-lifestyle influences. In addition to intracellular function, exogenous, circulating FABP expression can occur and is associated with specific disease states such as insulin resistance. A role for FABPs is increasingly being reported in tumor biology with elevated exogenous FABP expression being associated with tumor progression and invasiveness. However, a less clear role has been appreciated for dysregulated FABP expression during cell transformation and early expansion.
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Affiliation(s)
- Iain H McKillop
- Department of Surgery, Carolinas Medical Center, Atrium Health, Charlotte, NC 28203, USA
| | - Cara A Girardi
- Department of Surgery, Carolinas Medical Center, Atrium Health, Charlotte, NC 28203, USA
| | - Kyle J Thompson
- Department of Surgery, Carolinas Medical Center, Atrium Health, Charlotte, NC 28203, USA.
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7
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Different modes of barrel opening suggest a complex pathway of ligand binding in human gastrotropin. PLoS One 2019; 14:e0216142. [PMID: 31075121 PMCID: PMC6510414 DOI: 10.1371/journal.pone.0216142] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Accepted: 04/15/2019] [Indexed: 11/19/2022] Open
Abstract
Gastrotropin, the intracellular carrier of bile salts in the small intestine, binds two ligand molecules simultaneously in its internal cavity. The molecular rearrangements required for ligand entry are not yet fully clear. To improve our understanding of the binding process we combined molecular dynamics simulations with previously published structural and dynamic NMR parameters. The resulting ensembles reveal two distinct modes of barrel opening with one corresponding to the transition between the apo and holo states, whereas the other affecting different protein regions in both ligation states. Comparison of the calculated structures with NMR-derived parameters reporting on slow conformational exchange processes suggests that the protein undergoes partial unfolding along a path related to the second mode of the identified barrel opening motion.
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8
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Horváth G, Egyed O, Tang C, Kovács M, Micsonai A, Kardos J, Toke O. Ligand entry in human ileal bile acid-binding protein is mediated by histidine protonation. Sci Rep 2019; 9:4825. [PMID: 30886237 PMCID: PMC6423008 DOI: 10.1038/s41598-019-41180-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Accepted: 02/28/2019] [Indexed: 01/07/2023] Open
Abstract
Human ileal bile acid-binding protein (hI-BABP) has a key role in the intracellular transport of bile salts. To explore the role of histidine protonation in the binding process, the pH-dependence of bile salt binding and internal dynamics in hI-BABP was investigated using NMR spectroscopy and biophysical tools. Thermodynamic and kinetic measurements show an increase in the overall binding affinity and the association rate constant of the first binding step below the pKa of the histidines, suggesting that ligand binding is favoured by the protonated state. The overlap between residues exhibiting a high sensitivity to pH in their backbone amide chemical shifts and protein regions undergoing a global ms conformational exchange indicate a connection between the two processes. According to 15N NMR relaxation dispersion analysis, the slow motion is most pronounced at and above the pKa of the histidines. In agreement with the NMR measurements, MD simulations show a stabilization of the protein by histidine protonation. Hydrogen-bonding and van der Waals interactions mediating the flow of information between the C/D- and G/H-turn regions hosting the three histidines, suggest a complex way of pH-governed allosteric regulation of ligand entry involving a transition between a closed and a more open protein state.
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Affiliation(s)
- Gergő Horváth
- Laboratory for NMR Spectroscopy, Research Centre for Natural Sciences, Hungarian Academy of Sciences, 2 Magyar tudósok körútja, H-1117, Budapest, Hungary
| | - Orsolya Egyed
- Laboratory for NMR Spectroscopy, Research Centre for Natural Sciences, Hungarian Academy of Sciences, 2 Magyar tudósok körútja, H-1117, Budapest, Hungary
| | - Changguo Tang
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, 660 South Euclid Avenue, St. Louis, Missouri, 63110, USA
| | - Mihály Kovács
- Department of Biochemistry, ELTE-MTA "Momentum" Motor Enzymology Research Group, Eötvös Loránd University, Pázmány Péter sétány 1/C, H-1117, Budapest, Hungary
| | - András Micsonai
- Department of Biochemistry, MTA-ELTE NAP B Neuroimmunology Research Group, Institute of Biology, Eötvös Loránd University, Pázmány Péter sétány 1/C, H-1117, Budapest, Hungary
| | - József Kardos
- Department of Biochemistry, MTA-ELTE NAP B Neuroimmunology Research Group, Institute of Biology, Eötvös Loránd University, Pázmány Péter sétány 1/C, H-1117, Budapest, Hungary
| | - Orsolya Toke
- Laboratory for NMR Spectroscopy, Research Centre for Natural Sciences, Hungarian Academy of Sciences, 2 Magyar tudósok körútja, H-1117, Budapest, Hungary.
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9
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Horváth G, Biczók L, Majer Z, Kovács M, Micsonai A, Kardos J, Toke O. Structural insight into a partially unfolded state preceding aggregation in an intracellular lipid-binding protein. FEBS J 2017; 284:3637-3661. [DOI: 10.1111/febs.14264] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Revised: 08/15/2017] [Accepted: 09/05/2017] [Indexed: 12/15/2022]
Affiliation(s)
- Gergő Horváth
- Laboratory for NMR Spectroscopy; Research Centre for Natural Sciences; Hungarian Academy of Sciences; Budapest Hungary
| | - László Biczók
- Institute of Materials and Environmental Chemistry; Research Centre for Natural Sciences; Hungarian Academy of Sciences; Budapest Hungary
| | - Zsuzsa Majer
- Institute of Chemistry; Eötvös Loránd University; Budapest Hungary
| | - Mihály Kovács
- Department of Biochemistry; ELTE-MTA ‘Momentum’ Motor Enzymology Research Group; Eötvös Loránd University; Budapest Hungary
| | - András Micsonai
- Department of Biochemistry; MTA-ELTE NAP B Neuroimmunology Research Group; Institute of Biology; Eötvös Loránd University; Budapest Hungary
| | - József Kardos
- Department of Biochemistry; MTA-ELTE NAP B Neuroimmunology Research Group; Institute of Biology; Eötvös Loránd University; Budapest Hungary
| | - Orsolya Toke
- Laboratory for NMR Spectroscopy; Research Centre for Natural Sciences; Hungarian Academy of Sciences; Budapest Hungary
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10
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D'Onofrio M, Zanzoni S, Munari F, Monaco HL, Assfalg M, Capaldi S. The long variant of human ileal bile acid-binding protein associated with colorectal cancer exhibits sub-cellular localization and lipid binding behaviour distinct from those of the common isoform. Biochim Biophys Acta Gen Subj 2017; 1861:2315-2324. [PMID: 28689989 DOI: 10.1016/j.bbagen.2017.07.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Revised: 06/09/2017] [Accepted: 07/05/2017] [Indexed: 12/29/2022]
Abstract
BACKGROUND Ileal bile acid-binding protein, IBABP, participates in the intracellular trafficking of bile salts and influences their signaling activities. The recently discovered variant, IBABP-L, bearing an N-terminal 49-amino acid extension, was found to be associated with colorectal cancer and to protect cancer cells from the cytotoxic effects of deoxycholate. However, the precise function and the molecular properties of this variant are currently unknown. METHODS Bioinformatics tools and confocal microscopy were used to investigate the sub-cellular localization of IBABP-L; protein dynamics, ligand binding and interaction with membrane models were studied by 2D NMR and fluorescence spectroscopy. RESULTS Based on sub-cellular localization experiments we conclude that IBABP-L is targeted to the secretory pathway by a 24-residue signal peptide and, upon its cleavage, the mature protein is constitutively released into the extracellular space. Site-resolved NMR experiments indicated the distinct preference of primary and secondary bile salts to form either heterotypic or homotypic complexes with IBABP-L. The presence of the relatively dynamic N-terminal extension, originating only subtle conformational perturbations in the globular domain, was found to influence binding site occupation in IBABP-L as compared to IBABP. Even more pronounced differences were found in the tendency of the two variants to associate with phospholipid bilayers. CONCLUSIONS IBABP-L exhibits different sub-cellular localization, ligand-binding properties and membrane interaction propensity compared to the canonical short isoform. GENERAL SIGNIFICANCE Our results constitute an essential first step towards an understanding of the role of IBABP-L in bile salt trafficking and signaling under healthy and pathological conditions.
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Affiliation(s)
- Mariapina D'Onofrio
- Biomolecular NMR Laboratory, Department of Biotechnology, University of Verona, Ca' Vignal 1, Strada Le Grazie 15, 37134 Verona, Italy
| | - Serena Zanzoni
- Biomolecular NMR Laboratory, Department of Biotechnology, University of Verona, Ca' Vignal 1, Strada Le Grazie 15, 37134 Verona, Italy
| | - Francesca Munari
- Biomolecular NMR Laboratory, Department of Biotechnology, University of Verona, Ca' Vignal 1, Strada Le Grazie 15, 37134 Verona, Italy
| | - Hugo L Monaco
- Biocrystallography Laboratory, Department of Biotechnology, University of Verona, Ca' Vignal 1, Strada Le Grazie 15, 37134 Verona, Italy
| | - Michael Assfalg
- Biomolecular NMR Laboratory, Department of Biotechnology, University of Verona, Ca' Vignal 1, Strada Le Grazie 15, 37134 Verona, Italy.
| | - Stefano Capaldi
- Biocrystallography Laboratory, Department of Biotechnology, University of Verona, Ca' Vignal 1, Strada Le Grazie 15, 37134 Verona, Italy.
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11
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Cecconi F, Shahzad MA, Marini Bettolo Marconi U, Vulpiani A. Frequency-control of protein translocation across an oscillating nanopore. Phys Chem Chem Phys 2017; 19:11260-11272. [DOI: 10.1039/c6cp08156h] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The translocation of a lipid binding protein (LBP) is studied using a phenomenological coarse-grained computational model that simplifies both chain and pore geometry.
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Affiliation(s)
| | | | | | - Angelo Vulpiani
- Dipartimento di Fisica
- Università “Sapienza” di Roma
- Italy
- Centro Linceo Interdisciplinare “B. Segre”
- Accademia dei Lincei
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12
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Tomaselli S, Ramirez DOS, Carletto RA, Varesano A, Vineis C, Zanzoni S, Molinari H, Ragona L. Electrospun Lipid Binding Proteins Composite Nanofibers with Antibacterial Properties. Macromol Biosci 2016; 17. [DOI: 10.1002/mabi.201600300] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 09/13/2016] [Indexed: 01/24/2023]
Affiliation(s)
- Simona Tomaselli
- Istituto per lo Studio delle Macromolecole (ISMAC); CNR, via Corti 12 20133 Milano Italy
| | | | | | - Alessio Varesano
- Istituto per lo Studio delle Macromolecole (ISMAC); CNR, C.so G. Pella 16 13900 Biella Italy
| | - Claudia Vineis
- Istituto per lo Studio delle Macromolecole (ISMAC); CNR, C.so G. Pella 16 13900 Biella Italy
| | - Serena Zanzoni
- Dipartimento di Biotecnologie; Università degli Studi di Verona; Strada le Grazie 15 37134 Verona Italy
| | - Henriette Molinari
- Istituto per lo Studio delle Macromolecole (ISMAC); CNR, via Corti 12 20133 Milano Italy
| | - Laura Ragona
- Istituto per lo Studio delle Macromolecole (ISMAC); CNR, via Corti 12 20133 Milano Italy
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13
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Hendrick AG, Müller I, Willems H, Leonard PM, Irving S, Davenport R, Ito T, Reeves J, Wright S, Allen V, Wilkinson S, Heffron H, Bazin R, Turney J, Mitchell PJ. Identification and Investigation of Novel Binding Fragments in the Fatty Acid Binding Protein 6 (FABP6). J Med Chem 2016; 59:8094-102. [PMID: 27500412 DOI: 10.1021/acs.jmedchem.6b00869] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Fatty acid binding protein 6 (FABP6) is a potential drug discovery target, which, if inhibited, may have a therapeutic benefit for the treatment of diabetes. Currently, there are no published inhibitors of FABP6, and with the target believed to be amenable to fragment-based drug discovery, a structurally enabled program was initiated. This program successfully identified fragment hits using the surface plasmon resonance (SPR) platform. Several hits were validated with SAR and were found to be displaced by the natural ligand taurocholate. We report the first crystal structure of human FABP6 in the unbound form, in complex with cholate, and with one of the key fragments.
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Affiliation(s)
- Alan G Hendrick
- Takeda Cambridge , 418 Cambridge Science Park, Cambridge CB4 0PZ, United Kingdom
| | - Ilka Müller
- Charles River , Chesterford Research Park, Saffron Walden, Essex CB10 1XL, United Kingdom
| | - Henriëtte Willems
- Takeda Cambridge , 418 Cambridge Science Park, Cambridge CB4 0PZ, United Kingdom
| | - Philip M Leonard
- Charles River , Chesterford Research Park, Saffron Walden, Essex CB10 1XL, United Kingdom
| | - Steve Irving
- Charles River , Ingram Building, Parkwood Road, Canterbury, Kent CT2 7NH, United Kingdom
| | - Richard Davenport
- Takeda Cambridge , 418 Cambridge Science Park, Cambridge CB4 0PZ, United Kingdom
| | - Takashi Ito
- Biomolecular Research Laboratories, Takeda Pharmaceutical Company Limited , 26-1, Muraoka-Higashi 2-chome, Fujisawa 251-8555, Japan
| | - Jenny Reeves
- Takeda Cambridge , 418 Cambridge Science Park, Cambridge CB4 0PZ, United Kingdom
| | - Susanne Wright
- Takeda Cambridge , 418 Cambridge Science Park, Cambridge CB4 0PZ, United Kingdom
| | - Vivienne Allen
- Charles River , Chesterford Research Park, Saffron Walden, Essex CB10 1XL, United Kingdom
| | - Stephen Wilkinson
- Charles River , Chesterford Research Park, Saffron Walden, Essex CB10 1XL, United Kingdom
| | - Helen Heffron
- Takeda Cambridge , 418 Cambridge Science Park, Cambridge CB4 0PZ, United Kingdom
| | - Richard Bazin
- Charles River , Ingram Building, Parkwood Road, Canterbury, Kent CT2 7NH, United Kingdom
| | - Jennifer Turney
- Charles River , Chesterford Research Park, Saffron Walden, Essex CB10 1XL, United Kingdom
| | - Philip J Mitchell
- Takeda Cambridge , 418 Cambridge Science Park, Cambridge CB4 0PZ, United Kingdom
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