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Zeng Z, Ni J, Huang Z, Tan Q. Expression and functional analysis of Fushi Tarazu transcription factor 1 (FTZ-F1) in the regulation of steroid hormones during the gonad development of Fujian Oyster, Crassostrea angulata. Comp Biochem Physiol A Mol Integr Physiol 2024; 295:111668. [PMID: 38797241 DOI: 10.1016/j.cbpa.2024.111668] [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: 04/29/2024] [Revised: 05/22/2024] [Accepted: 05/23/2024] [Indexed: 05/29/2024]
Abstract
Crassostrea angulata, a major shellfish cultivated in Southern China, has experienced a notable surge in commercial value in recent years. Understanding the molecular mechanisms governing their reproductive processes holds significant implications for advancing aquaculture practices. In this study, we cloned the orphan nuclear receptor gene, Fushi Tarazu transcription factor 1 (FTZ-F1), of C. angulata and investigated its functional role in the gonadal development. The full-length cDNA of FTZ-F1 spans 2357 bp and encodes a protein sequence of 530 amino acids. Notably, the amino acid sequence of FTZ-F1 in C. angulata shares remarkable similarity with its homologues in other species, particularly in the DNA-binding region (>90%) and ligand-binding region (>44%). In C. angulata, the highest expression level of FTZ-F1 was observed in the ovary, exhibiting more than a 200-fold increase during the maturation stage compared to the initiation stage (P < 0.001). Specifically, FTZ-F1 was mainly expressed in the follicular cells surrounding the oocytes of C. angulata. Upon inhibiting FTZ-F1 gene expression in C. angulata through RNA interference (RNAi), a substantial reduction in the expression of genes involved in the synthesis of sex steroids in the gonads, including 3β-HSD, Cyp17, and follistatin, was observed. In addition, estradiol (E2) and testosterone (T) levels also showed a decrease upon FTZ-F1 silencing, resulting in a delayed gonadal development. These results indicate that FTZ-F1 acts as a steroidogenic factor, participating in the synthesis and regulation of steroid hormones and thus playing an important role in the reproductive and endocrine systems within oysters.
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Affiliation(s)
- Zhen Zeng
- Xiamen Key Laboratory of Marine Medicinal Natural Products Resources, Xiamen Medical College, Xiamen 361023, China; State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361005, China
| | - Jianbin Ni
- State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361005, China
| | - Zixia Huang
- School of Biology and Environmental Science, University College Dublin, Belfield, Dublin 4, Ireland.
| | - Qianglai Tan
- Xiamen Key Laboratory of Marine Medicinal Natural Products Resources, Xiamen Medical College, Xiamen 361023, China.
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2
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Chapagain P, Haratipour Z, Malabanan MM, Choi WJ, Blind RD. Bilirubin is a new ligand for nuclear receptor Liver Receptor Homolog-1. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.05.592606. [PMID: 38853895 PMCID: PMC11160564 DOI: 10.1101/2024.05.05.592606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2024]
Abstract
The nuclear receptor Liver Receptor Homolog-1 (LRH-1, NR5A2 ) binds to phospholipids that regulate important LRH-1 functions in the liver. A recent compound screen unexpectedly identified bilirubin, the product of liver heme metabolism, as a possible ligand for LRH-1. Here, we show unconjugated bilirubin directly binds LRH-1 with apparent K d =9.3uM, altering LRH-1 interaction with all transcriptional coregulator peptides tested. Bilirubin decreased LRH-1 protease sensitivity, consistent with MD simulations predicting bilirubin stably binds LRH-1 within the canonical ligand binding site. Bilirubin activated a luciferase reporter specific for LRH-1, dependent on co-expression with the bilirubin membrane transporter SLCO1B1 , but bilirubin failed to activate ligand-binding genetic mutants of LRH-1. Gene profiling in HepG2 cells shows bilirubin selectively regulated transcripts from endogenous LRH-1 ChIP-seq target genes, which was significantly attenuated by either genetic knockdown of LRH-1, or by a specific chemical competitor of LRH-1. Gene set enrichment suggests bilirubin and LRH-1 share roles in cholesterol metabolism and lipid efflux, thus we propose a new role for LRH-1 in directly sensing intracellular levels of bilirubin.
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3
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Chi ES, Stivison EA, Blind RD. SF-1 Induces Nuclear PIP2. Biomolecules 2023; 13:1509. [PMID: 37892191 PMCID: PMC10604688 DOI: 10.3390/biom13101509] [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: 09/01/2023] [Revised: 10/06/2023] [Accepted: 10/07/2023] [Indexed: 10/29/2023] Open
Abstract
Metazoan cell nuclei contain non-membrane pools of the phosphoinositide lipid PI(4,5)P2 (PIP2), but how this hydrophobic lipid exists within the aqueous nucleoplasm remains unclear. Steroidogenic Factor-1 (NR5A1, SF-1) is a nuclear receptor that binds PIP2 in vitro, and a co-crystal structure of the complex suggests the acyl chains of PIP2 are hidden in the hydrophobic core of the SF-1 protein while the PIP2 headgroup is solvent-exposed. This binding mode explains how SF-1 can solubilize nuclear PIP2; however, cellular evidence that SF-1 expression associates with nuclear PIP2 has been lacking. Here, we examined if tetracycline induction of SF-1 expression would associate with nuclear accumulation of PIP2, using antibodies directed against the PIP2 headgroup. Indeed, tetracycline induction of wild-type SF-1 induced a signal in the nucleus of HEK cells that cross-reacts with PIP2 antibodies, but did not cross-react with antibodies against the lower abundance phosphoinositide PI(3,4,5)P3 (PIP3). The nuclear PIP2 signal co-localized with FLAG-tagged SF-1 in the nuclear compartment. To determine if the nuclear PIP2 signal was dependent on the ability of SF-1 to bind PIP2, we examined a "pocket mutant" of SF-1 (A270W, L345F) shown to be deficient in phospholipid binding by mass spectrometry. Tetracycline induction of this pocket mutant SF-1 in HEK cells failed to induce a detectable PIP2 antibody cross-reactive signal, despite similar Tet-induced expression levels of the wild-type and pocket mutant SF-1 proteins in these cells. Together, these data are the first to suggest that expression of SF-1 induces a PIP2 antibody cross-reactive signal in the nucleus, consistent with X-ray crystallographic and biochemical evidence suggesting SF-1 binds PIP2 in human cells.
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Affiliation(s)
| | | | - Raymond D. Blind
- Department of Medicine, Division of Diabetes, Endocrinology and Metabolism, Vanderbilt University Medical Center, Nashville, TN 37232, USA
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4
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Cato ML, D'Agostino EH, Spurlin RM, Flynn AR, Cornelison JL, Johnson AM, Fujita RA, Abraham SM, Jui NT, Ortlund EA. Comparison of activity, structure, and dynamics of SF-1 and LRH-1 complexed with small molecule modulators. J Biol Chem 2023; 299:104921. [PMID: 37328104 PMCID: PMC10407255 DOI: 10.1016/j.jbc.2023.104921] [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: 12/16/2022] [Revised: 05/29/2023] [Accepted: 06/08/2023] [Indexed: 06/18/2023] Open
Abstract
Steroidogenic factor-1 (SF-1) is a phospholipid-sensing nuclear receptor expressed in the adrenal glands, gonads, and hypothalamus which controls steroidogenesis and metabolism. There is significant therapeutic interest in SF-1 because of its oncogenic properties in adrenocortical cancer. Synthetic modulators are attractive for targeting SF-1 for clinical and laboratory purposes due to the poor pharmaceutical properties of its native phospholipid ligands. While small molecule agonists targeting SF-1 have been synthesized, no crystal structures have been reported of SF-1 in complexes with synthetic compounds. This has prevented the establishment of structure-activity relationships that would enable better characterization of ligand-mediated activation and improvement in current chemical scaffolds. Here, we compare the effects of small molecules in SF-1 and its close homolog, liver receptor homolog-1 (LRH-1), and identify several molecules that specifically activate LRH-1. We also report the first crystal structure of SF-1 in complex with a synthetic agonist that displays low nanomolar affinity and potency for SF-1. We use this structure to explore the mechanistic basis for small molecule agonism of SF-1, especially compared to LRH-1, and uncover unique signaling pathways that drive LRH-1 specificity. Molecular dynamics simulations reveal differences in protein dynamics at the pocket mouth as well as ligand-mediated allosteric communication from this region to the coactivator binding interface. Our studies, therefore, shed important insight into the allostery driving SF-1 activity and show potential for modulation of LRH-1 over SF-1.
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Affiliation(s)
- Michael L Cato
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Emma H D'Agostino
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia, USA
| | | | - Autumn R Flynn
- Department of Chemistry, Emory University, Atlanta, Georgia, USA
| | | | - Alyssa M Johnson
- Department of Chemistry, Emory University, Atlanta, Georgia, USA
| | - Rei A Fujita
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Sarah M Abraham
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Nathan T Jui
- Department of Chemistry, Emory University, Atlanta, Georgia, USA
| | - Eric A Ortlund
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia, USA.
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5
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Lucafò M, Muzzo A, Marcuzzi M, Giorio L, Decorti G, Stocco G. Patient-derived organoids for therapy personalization in inflammatory bowel diseases. World J Gastroenterol 2022; 28:2636-2653. [PMID: 35979165 PMCID: PMC9260862 DOI: 10.3748/wjg.v28.i24.2636] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Revised: 03/21/2022] [Accepted: 05/17/2022] [Indexed: 02/06/2023] Open
Abstract
Inflammatory bowel diseases (IBDs) are chronic inflammatory disorders of the intestinal tract that have emerged as a growing problem in industrialized countries. Knowledge of IBD pathogenesis is still incomplete, and the most widely-accepted interpretation considers genetic factors, environmental stimuli, uncontrolled immune responses and altered intestinal microbiota composition as determinants of IBD, leading to dysfunction of the intestinal epithelial functions. In vitro models commonly used to study the intestinal barrier do not fully reflect the proper intestinal architecture. An important innovation is represented by organoids, 3D in vitro cell structures derived from stem cells that can self-organize into functional organ-specific structures. Organoids may be generated from induced pluripotent stem cells or adult intestinal stem cells of IBD patients and therefore retain their genetic and transcriptomic profile. These models are powerful pharmacological tools to better understand IBD pathogenesis, to study the mechanisms of action on the epithelial barrier of drugs already used in the treatment of IBD, and to evaluate novel target-directed molecules which could improve therapeutic strategies. The aim of this review is to illustrate the potential use of organoids for therapy personalization by focusing on the most significant advances in IBD research achieved through the use of adult stem cells-derived intestinal organoids.
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Affiliation(s)
- Marianna Lucafò
- Advanced Translational Diagnostics Laboratory, Institute for Maternal and Child Health-IRCCS “Burlo Garofolo”, Trieste 34137, Italy
| | - Antonella Muzzo
- Department of Medicine, Surgery and Health Sciences, University of Trieste, Trieste 34127, Italy
| | - Martina Marcuzzi
- Department of Life Sciences, University of Trieste, Trieste 34127, Italy
| | - Lorenzo Giorio
- Department of Life Sciences, University of Trieste, Trieste 34127, Italy
| | - Giuliana Decorti
- Advanced Translational Diagnostics Laboratory, Institute for Maternal and Child Health-IRCCS “Burlo Garofolo”, Trieste 34137, Italy
- Department of Medicine, Surgery and Health Sciences, University of Trieste, Trieste 34127, Italy
| | - Gabriele Stocco
- Advanced Translational Diagnostics Laboratory, Institute for Maternal and Child Health-IRCCS “Burlo Garofolo”, Trieste 34137, Italy
- Department of Life Sciences, University of Trieste, Trieste 34127, Italy
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6
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Wang HH, Portincasa P, Liu M, Wang DQH. Genetic Analysis of ABCB4 Mutations and Variants Related to the Pathogenesis and Pathophysiology of Low Phospholipid-Associated Cholelithiasis. Genes (Basel) 2022; 13:1047. [PMID: 35741809 PMCID: PMC9222727 DOI: 10.3390/genes13061047] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Accepted: 06/08/2022] [Indexed: 12/28/2022] Open
Abstract
Clinical studies have revealed that the ABCB4 gene encodes the phospholipid transporter on the canalicular membrane of hepatocytes, and its mutations and variants are the genetic basis of low phospholipid-associated cholelithiasis (LPAC), a rare type of gallstone disease caused by a single-gene mutation or variation. The main features of LPAC include a reduction or deficiency of phospholipids in bile, symptomatic cholelithiasis at <40 years of age, intrahepatic sludge and microlithiasis, mild chronic cholestasis, a high cholesterol/phospholipid ratio in bile, and recurrence of biliary symptoms after cholecystectomy. Needle-like cholesterol crystals, putatively “anhydrous” cholesterol crystallization at low phospholipid concentrations in model and native bile, are characterized in ABCB4 knockout mice, a unique animal model for LPAC. Gallbladder bile with only trace amounts of phospholipids in these mice is supersaturated with cholesterol, with lipid composition plotting in the left two-phase zone of the ternary phase diagram, consistent with “anhydrous” cholesterol crystallization. In this review, we summarize the molecular biology and physiological functions of ABCB4 and comprehensively discuss the latest advances in the genetic analysis of ABCB4 mutations and variations and their roles in the pathogenesis and pathophysiology of LPAC in humans, based on the results from clinical studies and mouse experiments. To date, approximately 158 distinct LPAC-causing ABCB4 mutations and variants in humans have been reported in the literature, indicating that it is a monogenic risk factor for LPAC. The elucidation of the ABCB4 function in the liver, the identification of ABCB4 mutations and variants in LPAC patients, and the exploration of gene therapy for ABCB4 deficiency in animal models can help us to better understand the cellular, molecular, and genetic mechanisms underlying the onset of the disease, and will pave the way for early diagnosis and prevention of susceptible subjects and effective intervention for LPAC in patients.
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Affiliation(s)
- Helen H. Wang
- Department of Medicine and Genetics, Division of Gastroenterology and Liver Diseases, Marion Bessin Liver Research Center, Einstein-Mount Sinai Diabetes Research Center, Albert Einstein College of Medicine, Bronx, NY 10461, USA;
| | - Piero Portincasa
- Department of Biomedical Sciences and Human Oncology, Clinica Medica “A. Murri”, University of Bari Medical School, 70124 Bari, Italy;
| | - Min Liu
- Department of Pathology and Laboratory Medicine, University of Cincinnati College of Medicine, Cincinnati, OH 45237, USA;
| | - David Q.-H. Wang
- Department of Medicine and Genetics, Division of Gastroenterology and Liver Diseases, Marion Bessin Liver Research Center, Einstein-Mount Sinai Diabetes Research Center, Albert Einstein College of Medicine, Bronx, NY 10461, USA;
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7
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Cato ML, Cornelison JL, Spurlin RM, Courouble VV, Patel AB, Flynn AR, Johnson AM, Okafor CD, Frank F, D’Agostino EH, Griffin PR, Jui NT, Ortlund EA. Differential Modulation of Nuclear Receptor LRH-1 through Targeting Buried and Surface Regions of the Binding Pocket. J Med Chem 2022; 65:6888-6902. [PMID: 35503419 PMCID: PMC10026694 DOI: 10.1021/acs.jmedchem.2c00235] [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] [Indexed: 11/29/2022]
Abstract
Liver receptor homologue-1 (LRH-1) is a phospholipid-sensing nuclear receptor that has shown promise as a target for alleviating intestinal inflammation and metabolic dysregulation in the liver. LRH-1 contains a large ligand-binding pocket, but generating synthetic modulators has been challenging. We have had recent success generating potent and efficacious agonists through two distinct strategies. We targeted residues deep within the pocket to enhance compound binding and residues at the mouth of the pocket to mimic interactions made by phospholipids. Here, we unite these two designs into one molecule to synthesize the most potent LRH-1 agonist to date. Through a combination of global transcriptomic, biochemical, and structural studies, we show that selective modulation can be driven through contacting deep versus surface polar regions in the pocket. While deep pocket contacts convey high affinity, contacts with the pocket mouth dominate allostery and provide a phospholipid-like transcriptional response in cultured cells.
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Affiliation(s)
- Michael L. Cato
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia 30322
| | | | | | | | - Anamika B. Patel
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Autumn R. Flynn
- Department of Chemistry, Emory University, Atlanta, Georgia 30322
| | | | - C. Denise Okafor
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Filipp Frank
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Emma H. D’Agostino
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia 30322
| | | | - Nathan T. Jui
- Department of Chemistry, Emory University, Atlanta, Georgia 30322
| | - Eric A. Ortlund
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia 30322
- Corresponding Author:
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8
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Mays SG, D'Agostino EH, Flynn AR, Huang X, Wang G, Liu X, Millings EJ, Okafor CD, Patel A, Cato ML, Cornelison JL, Melchers D, Houtman R, Moore DD, Calvert JW, Jui NT, Ortlund EA. A phospholipid mimetic targeting LRH-1 ameliorates colitis. Cell Chem Biol 2022; 29:1174-1186.e7. [PMID: 35316658 DOI: 10.1016/j.chembiol.2022.03.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 12/14/2021] [Accepted: 02/27/2022] [Indexed: 12/14/2022]
Abstract
Phospholipids are ligands for nuclear hormone receptors (NRs) that regulate transcriptional programs relevant to normal physiology and disease. Here, we demonstrate that mimicking phospholipid-NR interactions is a robust strategy to improve agonists of liver receptor homolog-1 (LRH-1), a therapeutic target for colitis. Conventional LRH-1 modulators only partially occupy the binding pocket, leaving vacant a region important for phospholipid binding and allostery. Therefore, we constructed a set of molecules with elements of natural phospholipids appended to a synthetic LRH-1 agonist. We show that the phospholipid-mimicking groups interact with the targeted residues in crystal structures and improve binding affinity, LRH-1 transcriptional activity, and conformational changes at a key allosteric site. The best phospholipid mimetic markedly improves colonic histopathology and disease-related weight loss in a murine T cell transfer model of colitis. This evidence of in vivo efficacy for an LRH-1 modulator in colitis represents a leap forward in agonist development.
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Affiliation(s)
- Suzanne G Mays
- Department of Biochemistry, Emory University, Atlanta, GA, USA
| | | | - Autumn R Flynn
- Department of Chemistry, Emory University, Atlanta, GA, USA
| | - Xiangsheng Huang
- Department of Molecular and Cell Biology, Baylor College of Medicine, Houston, TX, USA; Department of Pediatrics, Baylor College of Medicine and Texas Children's Hospital, Houston, TX, USA
| | - Guohui Wang
- Department of Molecular and Cell Biology, Baylor College of Medicine, Houston, TX, USA; Department of Pediatrics, Baylor College of Medicine and Texas Children's Hospital, Houston, TX, USA
| | - Xu Liu
- Department of Biochemistry, Emory University, Atlanta, GA, USA
| | - Elizabeth J Millings
- Department of Biochemistry, Emory University, Atlanta, GA, USA; Department of Surgery, Emory University, Atlanta, GA, USA
| | - C Denise Okafor
- Department of Biochemistry, Emory University, Atlanta, GA, USA
| | - Anamika Patel
- Department of Biochemistry, Emory University, Atlanta, GA, USA
| | - Michael L Cato
- Department of Biochemistry, Emory University, Atlanta, GA, USA
| | | | | | | | - David D Moore
- Department of Molecular and Cell Biology, Baylor College of Medicine, Houston, TX, USA; Department of Nutritional Sciences and Toxicology, University of California, Berkeley, Berkeley, CA, USA
| | - John W Calvert
- Department of Surgery, Emory University, Atlanta, GA, USA
| | - Nathan T Jui
- Department of Chemistry, Emory University, Atlanta, GA, USA.
| | - Eric A Ortlund
- Department of Biochemistry, Emory University, Atlanta, GA, USA.
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9
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Thorne JL, Cioccoloni G. Nuclear Receptors and Lipid Sensing. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1390:83-105. [DOI: 10.1007/978-3-031-11836-4_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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10
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Lang A, Isigkeit L, Schubert-Zsilavecz M, Merk D. The Medicinal Chemistry and Therapeutic Potential of LRH-1 Modulators. J Med Chem 2021; 64:16956-16973. [PMID: 34839661 DOI: 10.1021/acs.jmedchem.1c01663] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The ligand-activated transcription factor liver receptor homologue 1 (LRH-1, NR5A2) is involved in the regulation of metabolic homeostasis, including cholesterol and glucose balance. Preliminary evidence points to therapeutic potential of LRH-1 modulation in diabetes, hepatic diseases, inflammatory bowel diseases, atherosclerosis, and certain cancers, but because of a lack of suitable ligands, pharmacological control of LRH-1 has been insufficiently studied. Despite the availability of considerable structural knowledge on LRH-1, only a few ligand chemotypes have been developed, and potent, selective, and bioavailable tools to explore LRH-1 modulation in vivo are lacking. In view of the therapeutic potential of LRH-1 in prevalent diseases, improved chemical tools are needed to probe the beneficial and adverse effects of pharmacological LRH-1 modulation in sophisticated preclinical models and to further elucidate the receptor's molecular function.
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Affiliation(s)
- Alisa Lang
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, D-60438 Frankfurt, Germany
| | - Laura Isigkeit
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, D-60438 Frankfurt, Germany
| | | | - Daniel Merk
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, D-60438 Frankfurt, Germany.,Department of Pharmacy, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13, D-81377 Munich, Germany
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Overduin M, Kervin TA. The phosphoinositide code is read by a plethora of protein domains. Expert Rev Proteomics 2021; 18:483-502. [PMID: 34351250 DOI: 10.1080/14789450.2021.1962302] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
INTRODUCTION The proteins that decipher nucleic acid- and protein-based information are well known, however, those that read membrane-encoded information remain understudied. Here we report 70 different human, microbial and viral protein folds that recognize phosphoinositides (PIs), comprising the readers of a vast membrane code. AREAS COVERED Membrane recognition is best understood for FYVE, PH and PX domains, which exemplify hundreds of PI code readers. Comparable lipid interaction mechanisms may be mediated by kinases, adjacent C1 and C2 domains, trafficking arrestin, GAT and VHS modules, membrane-perturbing annexin, BAR, CHMP, ENTH, HEAT, syntaxin and Tubby helical bundles, multipurpose FERM, EH, MATH, PHD, PDZ, PROPPIN, PTB and SH2 domains, as well as systems that regulate receptors, GTPases and actin filaments, transfer lipids and assembled bacterial and viral particles. EXPERT OPINION The elucidation of how membranes are recognized has extended the genetic code to the PI code. Novel discoveries include PIP-stop and MET-stop residues to which phosphates and metabolites are attached to block phosphatidylinositol phosphate (PIP) recognition, memteins as functional membrane protein apparatuses, and lipidons as lipid "codons" recognized by membrane readers. At least 5% of the human proteome senses such membrane signals and allows eukaryotic organelles and pathogens to operate and replicate.
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Affiliation(s)
- Michael Overduin
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
| | - Troy A Kervin
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
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12
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Nuclear Phosphatidylinositol 3,4,5-Trisphosphate Interactome Uncovers an Enrichment in Nucleolar Proteins. Mol Cell Proteomics 2021; 20:100102. [PMID: 34048982 PMCID: PMC8255942 DOI: 10.1016/j.mcpro.2021.100102] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Accepted: 05/20/2021] [Indexed: 02/07/2023] Open
Abstract
Polyphosphoinositides (PPIns) play essential roles as lipid signaling molecules, and many of their functions have been elucidated in the cytoplasm. However, PPIns are also intranuclear where they contribute to chromatin remodeling, transcription, and mRNA splicing. The PPIn, phosphatidylinositol 3,4,5-trisphosphate (PtdIns(3,4,5)P3), has been mapped to the nucleus and nucleoli, but its role remains unclear in this subcellular compartment. To gain further insights into the nuclear functions of PtdIns(3,4,5)P3, we applied a previously developed quantitative MS-based approach to identify the targets of PtdIns(3,4,5)P3 from isolated nuclei. We identified 179 potential PtdIns(3,4,5)P3-interacting partners, and gene ontology analysis for the biological functions of this dataset revealed an enrichment in RNA processing/splicing, cytokinesis, protein folding, and DNA repair. Interestingly, about half of these interactors were common to nucleolar protein datasets, some of which had dual functions in rRNA processes and DNA repair, including poly(ADP-ribose) polymerase 1 (PARP1, now referred as ADP-ribosyltransferase 1). PARP1 was found to interact directly with PPIn via three polybasic regions in the DNA-binding domain and the linker located N-terminal of the catalytic region. PARP1 was shown to bind to PtdIns(3,4,5)P3 as well as phosphatidylinositol 3,4-bisphosphate in vitro and to colocalize with PtdIns(3,4,5)P3 in the nucleolus and with phosphatidylinositol 3,4-bisphosphate in nucleoplasmic foci. In conclusion, the PtdIns(3,4,5)P3 interactome reported here will serve as a resource to further investigate the molecular mechanisms underlying PtdIns(3,4,5)P3-mediated interactions in the nucleus and nucleolus. Phosphatidylinositol 3,4,5-trisphosphate (PtdIns(3,4,5)P3) localizes to nucleoli. PtdIns(3,4,5)P3 interactomics from isolated nuclei identifies nucleolar proteins. PARP1 interacts directly with polyphosphoinositides via several polybasic regions. PARP1 colocalizes with PtdIns(3,4,5)P3 in the nucleolus.
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13
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Bryant JM, Malabanan MM, Vanderloop BH, Nichols CM, Haratipour Z, Poon KT, Sherrod SD, McLean JA, Blind RD. The acyl chains of phosphoinositide PIP3 alter the structure and function of nuclear receptor steroidogenic factor-1. J Lipid Res 2021; 62:100081. [PMID: 33933440 PMCID: PMC8178125 DOI: 10.1016/j.jlr.2021.100081] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 04/01/2021] [Accepted: 04/05/2021] [Indexed: 11/28/2022] Open
Abstract
Nuclear receptors are transcription factors that bind lipids, an event that induces a structural conformation of the receptor that favors interaction with transcriptional coactivators. The nuclear receptor steroidogenic factor-1 (SF-1, NR5A1) binds the signaling phosphoinositides PI(4,5)P2 (PIP2) and PI(3,4,5)P3 (PIP3), and our previous crystal structures showed how the phosphoinositide headgroups regulate SF-1 function. However, what role the acyl chains play in regulating SF-1 structure remains unaddressed. Here, we used X-ray crystallography with in vitro binding and functional assays to examine how the acyl chains of PIP3 regulate human SF-1 ligand-binding domain structure and function. Altering acyl chain length and unsaturation regulates apparent binding of all tested phosphoinositides to SF-1. Mass spectrometry-based lipidomics data suggest C16 and C18 phospholipids preferentially associate with SF-1 expressed ectopically in bacteria. We then solved the 2.5 Å crystal structure of SF-1 bound to dioleoyl PIP3(18:1/18:1) to compare it with a matched structure of SF-1 bound to dipalmitoyl PIP3(16:0/16:0). The dioleoyl-bound structure was severely disordered in a specific SF-1 region associated with pathogenic human polymorphisms and within the coactivator-binding region critical for SF-1 function while inducing increased sensitivity to protease digestion in solution. Validating these structural observations, in vitro functional studies showed dioleoyl PIP3 induced 6-fold poorer affinity of a peroxisome proliferator-activated receptor gamma coactivator 1-alpha coactivator peptide for SF-1 compared with dipalmitoyl PIP3. Together, these data suggest the chemical nature of the phosphoinositide acyl chains controls the ordered state of specific, clinically important structural regions in SF-1, regulating SF-1 function in vitro.
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Affiliation(s)
- Jamal M Bryant
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - M Merced Malabanan
- Department of Medicine, Division of Diabetes, Endocrinology and Metabolism, Vanderbilt University Medical Center, Nashville, TN, USA; Vanderbilt Diabetes Research and Training Center, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Boden H Vanderloop
- Department of Medicine, Division of Diabetes, Endocrinology and Metabolism, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Charles M Nichols
- Center for Innovative Technology and Department of Chemistry, Vanderbilt University, Nashville, TN, USA
| | - Zeinab Haratipour
- Department of Medicine, Division of Diabetes, Endocrinology and Metabolism, Vanderbilt University Medical Center, Nashville, TN, USA; Vanderbilt Diabetes Research and Training Center, Vanderbilt University Medical Center, Nashville, TN, USA; Genomic Medicine Training Program, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Katrina T Poon
- Department of Medicine, Division of Diabetes, Endocrinology and Metabolism, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Stacy D Sherrod
- Center for Innovative Technology and Department of Chemistry, Vanderbilt University, Nashville, TN, USA
| | - John A McLean
- Center for Innovative Technology and Department of Chemistry, Vanderbilt University, Nashville, TN, USA
| | - Raymond D Blind
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN, USA; Department of Medicine, Division of Diabetes, Endocrinology and Metabolism, Vanderbilt University Medical Center, Nashville, TN, USA; Vanderbilt Diabetes Research and Training Center, Vanderbilt University Medical Center, Nashville, TN, USA; Genomic Medicine Training Program, Vanderbilt University School of Medicine, Nashville, TN, USA; Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA; Center for Structural Biology, Vanderbilt University School of Medicine, Nashville, TN, USA.
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14
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Sun Y, Demagny H, Schoonjans K. Emerging functions of the nuclear receptor LRH-1 in liver physiology and pathology. Biochim Biophys Acta Mol Basis Dis 2021; 1867:166145. [PMID: 33862147 DOI: 10.1016/j.bbadis.2021.166145] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 03/30/2021] [Accepted: 04/08/2021] [Indexed: 02/06/2023]
Abstract
Nuclear receptors play pleiotropic roles in cell differentiation, development, proliferation, and metabolic processes to govern liver physiology and pathology. The nuclear receptor, liver receptor homolog-1 (LRH-1, NR5A2), originally identified in the liver as a regulator of bile acid and cholesterol homeostasis, was recently recognized to coordinate a multitude of other hepatic metabolic processes, including glucose and lipid processing, methyl group sensing, and cellular stress responses. In this review, we summarize the physiological and pathophysiological functions of LRH-1 in the liver, as well as the molecular mechanisms underlying these processes. This review also focuses on the recent advances highlighting LRH-1 as an attractive target for liver-associated diseases, such as non-alcoholic fatty liver disease (NAFLD) and hepatocellular carcinoma (HCC).
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Affiliation(s)
- Yu Sun
- Institute of Bioengineering, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - Hadrien Demagny
- Institute of Bioengineering, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - Kristina Schoonjans
- Institute of Bioengineering, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland.
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15
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Mays SG, Stec J, Liu X, D'Agostino EH, Whitby RJ, Ortlund EA. Enantiomer-specific activities of an LRH-1 and SF-1 dual agonist. Sci Rep 2020; 10:22279. [PMID: 33335203 PMCID: PMC7747700 DOI: 10.1038/s41598-020-79251-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Accepted: 11/09/2020] [Indexed: 12/28/2022] Open
Abstract
Chirality is an important consideration in drug development: it can influence recognition of the intended target, pharmacokinetics, and off-target effects. Here, we investigate how chirality affects the activity and mechanism of action of RJW100, a racemic agonist of the nuclear receptors liver receptor homolog-1 (LRH-1) and steroidogenic factor-1 (SF-1). LRH-1 and SF-1 modulators are highly sought as treatments for metabolic and neoplastic diseases, and RJW100 has one of the few scaffolds shown to activate them. However, enantiomer-specific effects on receptor activation are poorly understood. We show that the enantiomers have similar binding affinities, but RR-RJW100 stabilizes both receptors and is 46% more active than SS-RJW100 in LRH-1 luciferase reporter assays. We present an LRH-1 crystal structure that illuminates striking mechanistic differences: SS-RJW100 adopts multiple configurations in the pocket and fails to make an interaction critical for activation by RR-RJW100. In molecular dynamics simulations, SS-RJW100 attenuates intramolecular signalling important for coregulator recruitment, consistent with previous observations that it weakly recruits coregulators in vitro. These studies provide a rationale for pursuing enantiomerically pure RJW100 derivatives: they establish RR-RJW100 as the stronger LRH-1 agonist and identify a potential for optimizing the SS-RJW100 scaffold for antagonist design.
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Affiliation(s)
- Suzanne G Mays
- Department of Biochemistry, Emory University, Atlanta, GA, 30322, USA
- Centre for Genomic Regulation, Carrer Dr. Aiguader, 88, 08003, Barcelona, Spain
| | - Józef Stec
- School of Chemistry, University of Southampton, Southampton, Hants, SO17, United Kingdom
- Department of Pharmaceutical Sciences, College of Pharmacy, Marshall B. Ketchum University, 2575 Yorba Linda Blvd, Fullerton, CA, 82831, USA
| | - Xu Liu
- Department of Biochemistry, Emory University, Atlanta, GA, 30322, USA
| | - Emma H D'Agostino
- Department of Biochemistry, Emory University, Atlanta, GA, 30322, USA
| | - Richard J Whitby
- School of Chemistry, University of Southampton, Southampton, Hants, SO17, United Kingdom
| | - Eric A Ortlund
- Department of Biochemistry, Emory University, Atlanta, GA, 30322, USA.
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16
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Cestari I, Stuart K. The phosphoinositide regulatory network in Trypanosoma brucei: Implications for cell-wide regulation in eukaryotes. PLoS Negl Trop Dis 2020; 14:e0008689. [PMID: 33119588 PMCID: PMC7595295 DOI: 10.1371/journal.pntd.0008689] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The unicellular eukaryote Trypanosoma brucei undergoes extensive cellular and developmental changes during its life cycle. These include regulation of mammalian stage surface antigen variation and surface composition changes between life stages; switching between glycolysis and oxidative phosphorylation; differential mRNA editing; and changes in posttranscriptional gene expression, protein trafficking, organellar function, and cell morphology. These diverse events are coordinated and controlled throughout parasite development, maintained in homeostasis at each life stage, and are essential for parasite survival in both the host and insect vector. Described herein are the enzymes and metabolites of the phosphatidylinositol (PI) cellular regulatory network, its integration with other cellular regulatory systems that collectively control and coordinate these numerous cellular processes, including cell development and differentiation and the many associated complex processes in multiple subcellular compartments. We conclude that this regulation is the product of the organization of these enzymes within the cellular architecture, their activities, metabolite fluxes, and responses to environmental changes via signal transduction and other processes. We describe a paradigm for how these enzymes and metabolites could function to control and coordinate multiple cellular functions. The significance of the PI system's regulatory functions in single-celled eukaryotes to metazoans and their potential as chemotherapeutic targets are indicated.
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Affiliation(s)
- Igor Cestari
- Institute of Parasitology, McGill University, Sainte-Anne-de-Bellevue, Quebec, Canada
- Division of Experimental Medicine, McGill University, Montreal, Quebec, Canada
- * E-mail: (IC); (KS)
| | - Kenneth Stuart
- Center for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, Washington, United States of America
- Department of Global Health, University of Washington, Seattle, Washington, United States of America
- * E-mail: (IC); (KS)
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17
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Seacrist CD, Kuenze G, Hoffmann RM, Moeller BE, Burke JE, Meiler J, Blind RD. Integrated Structural Modeling of Full-Length LRH-1 Reveals Inter-domain Interactions Contribute to Receptor Structure and Function. Structure 2020; 28:830-846.e9. [PMID: 32433991 DOI: 10.1016/j.str.2020.04.020] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 03/03/2020] [Accepted: 04/27/2020] [Indexed: 01/06/2023]
Abstract
Liver receptor homolog-1 (LRH-1; NR5A2) is a nuclear receptor that regulates a diverse array of biological processes. In contrast to dimeric nuclear receptors, LRH-1 is an obligate monomer and contains a subtype-specific helix at the C terminus of the DNA-binding domain (DBD), termed FTZ-F1. Although detailed structural information is available for individual domains of LRH-1, it is unknown how these domains exist in the intact nuclear receptor. Here, we developed an integrated structural model of human full-length LRH-1 using a combination of HDX-MS, XL-MS, Rosetta computational docking, and SAXS. The model predicts the DBD FTZ-F1 helix directly interacts with ligand binding domain helix 2. We confirmed several other predicted inter-domain interactions via structural and functional analyses. Comparison between the LRH-1/Dax-1 co-crystal structure and the integrated model predicted and confirmed Dax-1 co-repressor to modulate LRH-1 inter-domain dynamics. Together, these data support individual LRH-1 domains interacting to influence receptor structure and function.
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Affiliation(s)
- Corey D Seacrist
- Department of Pharmacology, Vanderbilt University, Nashville, TN, USA; Center for Structural Biology, Vanderbilt University, Nashville, TN, USA
| | - Georg Kuenze
- Department of Chemistry, Vanderbilt University, Nashville, TN, USA; Center for Structural Biology, Vanderbilt University, Nashville, TN, USA
| | - Reece M Hoffmann
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, Canada
| | - Brandon E Moeller
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, Canada
| | - John E Burke
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, Canada
| | - Jens Meiler
- Department of Pharmacology, Vanderbilt University, Nashville, TN, USA; Department of Chemistry, Vanderbilt University, Nashville, TN, USA; Institute for Drug Discovery, Leipzig University, Leipzig, Germany; Center for Structural Biology, Vanderbilt University, Nashville, TN, USA.
| | - Raymond D Blind
- Department of Pharmacology, Vanderbilt University, Nashville, TN, USA; Department of Medicine, Division of Diabetes Endocrinology and Metabolism, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Biochemistry, Vanderbilt University, Nashville, TN, USA; Center for Structural Biology, Vanderbilt University, Nashville, TN, USA.
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18
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D’Agostino EH, Flynn AR, Cornelison JL, Mays SG, Patel A, Jui NT, Ortlund EA. Development of a Versatile and Sensitive Direct Ligand Binding Assay for Human NR5A Nuclear Receptors. ACS Med Chem Lett 2020; 11:365-370. [PMID: 32184971 DOI: 10.1021/acsmedchemlett.9b00442] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Accepted: 11/21/2019] [Indexed: 02/07/2023] Open
Abstract
As regulators of steroidogenesis, development, and metabolism, the nuclear receptor 5A (NR5A) subfamily members steroidogenic factor 1 (SF-1) and liver receptor homologue 1 (LRH-1) are important pharmacological targets for cancers and metabolic diseases. Evaluation of small molecule modulators and candidate endogenous ligands for these orphan receptors has been hindered by the lack of accessible, robust direct-binding assays. Here, we leverage the potency of our new NR5A agonist (6N) to create a high-affinity probe for fluorescence polarization competition assays by conjugating 6N to fluorescein (FAM). The 6N-FAM probe tightly binds the NR5A receptors and detects direct binding of synthetic and phospholipid ligands. For 25 LRH-1 agonists, affinity predicts potency in cellular activation assays, demonstrating the potential for this assay in drug discovery. Moreover, phospholipids dilauroylphosphatidylcholine and phosphatidylinositol(4,5)phosphate bind with high affinity, demonstrating this assay is robust for evaluation of candidate endogenous ligands for human NR5A receptors.
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19
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Choi S, Dong B, Lin CCJ, Heo MJ, Ho Kim K, Sun Z, Wagner M, Suh JM, Wang MC, Moore DD, Moore DD. Methyl-Sensing Nuclear Receptor Liver Receptor Homolog-1 Regulates Mitochondrial Function in Mouse Hepatocytes. Hepatology 2020; 71:1055-1069. [PMID: 31355949 PMCID: PMC6987012 DOI: 10.1002/hep.30884] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Accepted: 07/23/2019] [Indexed: 12/13/2022]
Abstract
BACKGROUND AND AIMS Liver receptor homolog-1 (LRH-1; NR5A2) is a nuclear receptor that regulates metabolic homeostasis in the liver. Previous studies identified phosphatidylcholines as potential endogenous agonist ligands for LRH-1. In the liver, distinct subsets of phosphatidylcholine species are generated by two different pathways: choline addition to phosphatidic acid through the Kennedy pathway and trimethylation of phosphatidylethanolamine through phosphatidylethanolamine N-methyl transferase (PEMT). APPROACH AND RESULTS Here, we report that a PEMT-LRH-1 pathway specifically couples methyl metabolism and mitochondrial activities in hepatocytes. We show that the loss of Lrh-1 reduces mitochondrial number, basal respiration, beta-oxidation, and adenosine triphosphate production in hepatocytes and decreases expression of mitochondrial biogenesis and beta-oxidation genes. In contrast, activation of LRH-1 by its phosphatidylcholine agonists exerts opposite effects. While disruption of the Kennedy pathway does not affect the LRH-1-mediated regulation of mitochondrial activities, genetic or pharmaceutical inhibition of the PEMT pathway recapitulates the effects of Lrh-1 knockdown on mitochondria. Furthermore, we show that S-adenosyl methionine, a cofactor required for PEMT, is sufficient to induce Lrh-1 transactivation and consequently mitochondrial biogenesis. CONCLUSIONS A PEMT-LRH-1 axis regulates mitochondrial biogenesis and beta-oxidation in hepatocytes.
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Affiliation(s)
- Sungwoo Choi
- Program in Developmental Biology, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Bingning Dong
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA
| | - Chih-Chun Janet Lin
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Mi Jeong Heo
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA
| | - Kang Ho Kim
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA
| | - Zhen Sun
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA
| | - Martin Wagner
- Division of Gastroenterology and Hepatology, Medical University Graz, Graz, Austria
| | - Jae Myoung Suh
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
| | - Meng C. Wang
- Program in Developmental Biology, Baylor College of Medicine, Houston, Texas 77030, USA;,Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA;,Correspondence: David D. Moore, Department of Molecular and Cellular Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX, 77030, USA, Phone: 713-798-3313, Fax: 713-798-3017, , Meng C. Wang, Huffington Center on Aging, Baylor College of Medicine, One Baylor Plaza, Houston, TX, 77030, USA, Phone: 713-798-1566,
| | - David D. Moore
- Program in Developmental Biology, Baylor College of Medicine, Houston, Texas 77030, USA;,Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, USA;,Correspondence: David D. Moore, Department of Molecular and Cellular Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX, 77030, USA, Phone: 713-798-3313, Fax: 713-798-3017, , Meng C. Wang, Huffington Center on Aging, Baylor College of Medicine, One Baylor Plaza, Houston, TX, 77030, USA, Phone: 713-798-1566,
| | - David D. Moore
- Program in Developmental Biology Baylor College of Medicine Houston TX
- Department of Molecular and Cellular Biology Baylor College of Medicine Houston TX
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20
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Mays SG, Flynn AR, Cornelison JL, Okafor CD, Wang H, Wang G, Huang X, Donaldson HN, Millings EJ, Polavarapu R, Moore DD, Calvert JW, Jui NT, Ortlund EA. Development of the First Low Nanomolar Liver Receptor Homolog-1 Agonist through Structure-guided Design. J Med Chem 2019; 62:11022-11034. [PMID: 31419141 PMCID: PMC10026690 DOI: 10.1021/acs.jmedchem.9b00753] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
As a key regulator of metabolism and inflammation, the orphan nuclear hormone receptor, liver receptor homolog-1 (LRH-1), has potential as a therapeutic target for diabetes, nonalcoholic fatty liver disease, and inflammatory bowel diseases (IBD). Discovery of LRH-1 modulators has been difficult, in part due to the tendency for synthetic compounds to bind unpredictably within the lipophilic binding pocket. Using a structure-guided approach, we exploited a newly discovered polar interaction to lock agonists in a consistent orientation. This enabled the discovery of the first low nanomolar LRH-1 agonist, one hundred times more potent than the best previous modulator. We elucidate a novel mechanism of action that relies upon specific polar interactions deep in the LRH-1 binding pocket. In an organoid model of IBD, the new agonist increases expression of LRH-1-controlled steroidogenic genes and promotes anti-inflammatory gene expression changes. These studies constitute major progress in developing LRH-1 modulators with potential clinical utility.
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Affiliation(s)
- Suzanne G. Mays
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia 30322, USA
| | - Autumn R. Flynn
- Department of Chemistry, Emory University, Atlanta, Georgia 30322, USA
| | | | - C. Denise Okafor
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia 30322, USA
| | - Hongtao Wang
- Department of Pediatrics, Section of Gastroenterology, Baylor College of Medicine and Texas Children’s Hospital, Houston, Texas 77030, USA
| | - Guohui Wang
- Department of Pediatrics, Section of Gastroenterology, Baylor College of Medicine and Texas Children’s Hospital, Houston, Texas 77030, USA
| | - Xiangsheng Huang
- Department of Pediatrics, Section of Gastroenterology, Baylor College of Medicine and Texas Children’s Hospital, Houston, Texas 77030, USA
| | - Heather N. Donaldson
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia 30322, USA
| | - Elizabeth J. Millings
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia 30322, USA
- Department of Surgery, Carlyle Fraser Heart Center, Emory University, Atlanta, Georgia 30322, USA
| | - Rohini Polavarapu
- Department of Surgery, Carlyle Fraser Heart Center, Emory University, Atlanta, Georgia 30322, USA
| | - David D. Moore
- Department of Molecular and Cell Biology, Baylor College of Medicine, Houston, Texas 77030, USA
| | - John W. Calvert
- Department of Surgery, Carlyle Fraser Heart Center, Emory University, Atlanta, Georgia 30322, USA
| | - Nathan T. Jui
- Department of Chemistry, Emory University, Atlanta, Georgia 30322, USA
| | - Eric A. Ortlund
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia 30322, USA
- Corresponding Author Eric A. Ortlund, 1525 Clifton Rd. G235, Atlanta, GA 30322,
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21
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Xu L, Chen Z, Shao K, Wang Y, Cui L, Guo N. Rational discovery of novel type-III FTF antagonists to competitively suppress TIF-2 coactivation in liver cancer. J Recept Signal Transduct Res 2019; 39:304-311. [PMID: 31755335 DOI: 10.1080/10799893.2019.1690513] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- Linlin Xu
- Department of Laboratory Medicine, The First People’s Hospital of Yancheng City, the Fourth Affiliated Hospital of Nantong University, Yancheng, China
| | - Zhongming Chen
- Department of Laboratory Medicine, The First People’s Hospital of Yancheng City, the Fourth Affiliated Hospital of Nantong University, Yancheng, China
| | - Keke Shao
- Department of Laboratory Medicine, The First People’s Hospital of Yancheng City, the Fourth Affiliated Hospital of Nantong University, Yancheng, China
| | - Yungang Wang
- Department of Laboratory Medicine, The First People’s Hospital of Yancheng City, the Fourth Affiliated Hospital of Nantong University, Yancheng, China
| | - Leilei Cui
- Department of Laboratory Medicine, The First People’s Hospital of Yancheng City, the Fourth Affiliated Hospital of Nantong University, Yancheng, China
| | - Naizhou Guo
- Department of Laboratory Medicine, The First People’s Hospital of Yancheng City, the Fourth Affiliated Hospital of Nantong University, Yancheng, China
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22
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Structural analyses of inositol phosphate second messengers bound to signaling effector proteins. Adv Biol Regul 2019; 75:100667. [PMID: 31648945 DOI: 10.1016/j.jbior.2019.100667] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Revised: 09/17/2019] [Accepted: 09/30/2019] [Indexed: 01/02/2023]
Abstract
The higher-order inositol phosphate second messengers inositol tetrakisphosphate (IP4), inositol pentakisphosphate (IP5) and inositol hexakisphosphate (IP6) are important signaling molecules that regulate DNA-damage repair, cohesin dynamics, RNA-editing, retroviral assembly, nuclear transport, phosphorylation, acetylation, crotonylation, and ubiquitination. This functional diversity has made understanding how inositol polyphosphates regulate cellular processes challenging to dissect. However, some inositol phosphates have been unexpectedly found in X-ray crystal structures, occasionally revealing structural and mechanistic details of effector protein regulation before functional consequences have been described. This review highlights a sampling of crystal structures describing the interaction between inositol phosphates and protein effectors. This list includes the RNA editing enzyme "adenosine deaminase that acts on RNA 2" (ADAR2), the Pds5B regulator of cohesin dynamics, the class 1 histone deacetylases (HDACs) HDAC1 and HDAC3, and the PH domain of Bruton's tyrosine kinase (Btk). One of the most important enzymes responsible for higher-order inositol phosphate synthesis is inositol polyphosphate multikinase (IPMK), which plays dual roles in both inositol and phosphoinositide signaling. Structures of phosphoinositide lipid binding proteins have also revealed new aspects of protein effector regulation, as mediated by the nuclear receptors Steroidogenic Factor-1 (SF-1, NR5A2) and Liver Receptor Homolog-1 (LRH-1, NR5A2). Together, these studies underscore the structural diversity in binding interactions between effector proteins and inositol phosphate small signaling molecules, and further support that detailed structural studies can lead to new biological discovery.
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23
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Clarke BP, Logeman BL, Hale AT, Luka Z, York JD. A synthetic biological approach to reconstitution of inositide signaling pathways in bacteria. Adv Biol Regul 2019; 73:100637. [PMID: 31378699 DOI: 10.1016/j.jbior.2019.100637] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 07/01/2019] [Accepted: 07/04/2019] [Indexed: 11/19/2022]
Abstract
Inositide lipid (PIP) and soluble (IP) signaling pathways produce essential cellular codes conserved in eukaryotes. In many cases, deconvoluting metabolic and functional aspects of individual pathways are confounded by promiscuity and multiplicity of PIP and IP kinases and phosphatases. We report a molecular genetic approach that reconstitutes eukaryotic inositide lipid and soluble pathways in a prokaryotic cell which inherently lack inositide kinases and phosphatases in their genome. By expressing synthetic cassettes of eukaryotic genes, we have reconstructed the heterologous formation of a range of inositide lipids, including PI(3)P, PI(4,5)P2 and PIP3. In addition, we report the reconstruction of lipid-dependent production of inositol hexakisphosphate (IP6). Our synthetic system is scalable, reduces confounding metabolic issues, for example it is devoid of inositide phosphatases and orthologous kinases, and enables accurate characterization gene product enzymatic activity and substrate selectivity. This genetically engineered tool is designed to help interpret metabolic pathways and may facilitate in vivo testing of regulators and small molecule inhibitors. In summary, heterologous expression of inositide pathways in bacteria provide a malleable experimental platform for aiding signaling biologists and offers new insights into metabolism of these essential pathways.
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Affiliation(s)
- Bradley P Clarke
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Brandon L Logeman
- Department of Pharmacology and Cancer Biology, Duke University, Durham, NC, USA
| | - Andrew T Hale
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Zigmund Luka
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - John D York
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA; Department of Pharmacology and Cancer Biology, Duke University, Durham, NC, USA.
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24
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Polyphosphoinositides in the nucleus: Roadmap of their effectors and mechanisms of interaction. Adv Biol Regul 2019; 72:7-21. [PMID: 31003946 DOI: 10.1016/j.jbior.2019.04.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 04/02/2019] [Accepted: 04/03/2019] [Indexed: 01/01/2023]
Abstract
Biomolecular interactions between proteins and polyphosphoinositides (PPIn) are essential in the regulation of the vast majority of cellular processes. Consequently, alteration of these interactions is implicated in the development of many diseases. PPIn are phosphorylated derivatives of phosphatidylinositol and consist of seven species with different phosphate combinations. PPIn signal by recruiting proteins via canonical domains or short polybasic motifs. Although their actions are predominantly documented on cytoplasmic membranes, six of the seven PPIn are present within the nucleus together with the PPIn kinases, phosphatases and phospholipases that regulate their turnover. Importantly, the contribution of nuclear PPIn in the regulation of nuclear processes has led to an increased recognition of their importance compared to their more accepted cytoplasmic roles. This review summarises our knowledge on the identification and functional characterisation of nuclear PPIn-effector proteins as well as their mode of interactions, which tend to favour polybasic motifs.
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25
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Flynn AR, Mays SG, Ortlund EA, Jui NT. Development of Hybrid Phospholipid Mimics as Effective Agonists for Liver Receptor Homologue-1. ACS Med Chem Lett 2018; 9:1051-1056. [PMID: 30344916 DOI: 10.1021/acsmedchemlett.8b00361] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Accepted: 09/04/2018] [Indexed: 01/18/2023] Open
Abstract
The orphan nuclear receptor Liver Receptor Homologue-1 (LRH-1) is an emerging drug target for metabolic disorders. The most effective known LRH-1 modulators are phospholipids or synthetic hexahydropentalene compounds. While both classes have micromolar efficacy, they target different portions of the ligand binding pocket and activate LRH-1 through different mechanisms. Guided by crystallographic data, we combined aspects of both ligand classes into a single scaffold, resulting in the most potent and efficacious LRH-1 agonists to date.
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26
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Bayrer JR, Wang H, Nattiv R, Suzawa M, Escusa HS, Fletterick RJ, Klein OD, Moore DD, Ingraham HA. LRH-1 mitigates intestinal inflammatory disease by maintaining epithelial homeostasis and cell survival. Nat Commun 2018; 9:4055. [PMID: 30305617 PMCID: PMC6180039 DOI: 10.1038/s41467-018-06137-w] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Accepted: 07/27/2018] [Indexed: 02/06/2023] Open
Abstract
Epithelial dysfunction and crypt destruction are defining features of inflammatory bowel disease (IBD). However, current IBD therapies targeting epithelial dysfunction are lacking. The nuclear receptor LRH-1 (NR5A2) is expressed in intestinal epithelium and thought to contribute to epithelial renewal. Here we show that LRH-1 maintains intestinal epithelial health and protects against inflammatory damage. Knocking out LRH-1 in murine intestinal organoids reduces Notch signaling, increases crypt cell death, distorts the cellular composition of the epithelium, and weakens the epithelial barrier. Human LRH-1 (hLRH-1) rescues epithelial integrity and when overexpressed, mitigates inflammatory damage in murine and human intestinal organoids, including those derived from IBD patients. Finally, hLRH-1 greatly reduces disease severity in T-cell-mediated murine colitis. Together with the failure of a ligand-incompetent hLRH-1 mutant to protect against TNFα-damage, these findings provide compelling evidence that hLRH-1 mediates epithelial homeostasis and is an attractive target for intestinal disease. Inflammatory bowel disease is characterised by epithelial dysfunction. Here the authors show that loss of the nuclear receptor LRH-1 leads to epithelial disruption by altering Notch signaling in mouse intestinal organoids, and that LRH-1 overexpression ameliorates immune-mediated colitis in a mouse model.
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Affiliation(s)
- James R Bayrer
- Department of Pediatrics, Division of Gastroenterology, University of California San Francisco, Mission Bay Campus, San Francisco, CA, 94158, USA.,Department of Cellular and Molecular Pharmacology, University of California San Francisco, Mission Bay Campus, San Francisco, CA, 94158, USA
| | - Hongtao Wang
- Department of Pediatrics, Division of Gastroenterology, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Roy Nattiv
- Department of Pediatrics, Division of Gastroenterology, University of California San Francisco, Mission Bay Campus, San Francisco, CA, 94158, USA
| | - Miyuki Suzawa
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, Mission Bay Campus, San Francisco, CA, 94158, USA
| | - Hazel S Escusa
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, Mission Bay Campus, San Francisco, CA, 94158, USA
| | - Robert J Fletterick
- Department of Biochemistry and Biophysics, University of California San Francisco, Mission Bay Campus, San Francisco, CA, 94158, USA
| | - Ophir D Klein
- Department of Orofacial Sciences & Program in Craniofacial Biology, University of California San Francisco, Mission Bay Campus, San Francisco, CA, 94158, USA.,Department of Pediatrics, Division of Genetics, University of California San Francisco, Mission Bay Campus, San Francisco, CA, 94158, USA
| | - David D Moore
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, 77030, USA.
| | - Holly A Ingraham
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, Mission Bay Campus, San Francisco, CA, 94158, USA.
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27
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Bryant JM, Blind RD. Signaling through non-membrane nuclear phosphoinositide binding proteins in human health and disease. J Lipid Res 2018; 60:299-311. [PMID: 30201631 DOI: 10.1194/jlr.r088518] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Revised: 08/22/2018] [Indexed: 12/22/2022] Open
Abstract
Phosphoinositide membrane signaling is critical for normal physiology, playing well-known roles in diverse human pathologies. The basic mechanisms governing phosphoinositide signaling within the nucleus, however, have remained deeply enigmatic owing to their presence outside the nuclear membranes. Over 40% of nuclear phosphoinositides can exist in this non-membrane state, held soluble in the nucleoplasm by nuclear proteins that remain largely unidentified. Recently, two nuclear proteins responsible for solubilizing phosphoinositides were identified, steroidogenic factor-1 (SF-1; NR5A1) and liver receptor homolog-1 (LRH-1; NR5A2), along with two enzymes that directly remodel these phosphoinositide/protein complexes, phosphatase and tensin homolog (PTEN; MMAC) and inositol polyphosphate multikinase (IPMK; ipk2). These new footholds now permit the assignment of physiological functions for nuclear phosphoinositides in human diseases, such as endometriosis, nonalcoholic fatty liver disease/steatohepatitis, glioblastoma, and hepatocellular carcinoma. The unique nature of nuclear phosphoinositide signaling affords extraordinary clinical opportunities for new biomarkers, diagnostics, and therapeutics. Thus, phosphoinositide biology within the nucleus may represent the next generation of low-hanging fruit for new drugs, not unlike what has occurred for membrane phosphatidylinositol 3-kinase drug development. This review connects recent basic science discoveries in nuclear phosphoinositide signaling to clinical pathologies, with the hope of inspiring development of new therapies.
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Affiliation(s)
- Jamal M Bryant
- Departments of Pharmacology, Biochemistry, and Medicine, Division of Diabetes, Endocrinology, and Metabolism, Vanderbilt Diabetes Research and Training Center, Vanderbilt University School of Medicine, Nashville, TN 37232
| | - Raymond D Blind
- Departments of Pharmacology, Biochemistry, and Medicine, Division of Diabetes, Endocrinology, and Metabolism, Vanderbilt Diabetes Research and Training Center, Vanderbilt University School of Medicine, Nashville, TN 37232
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28
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Zhao J, Gao S, Zhu Y, Shen X. Significant role of microRNA‑219‑5p in diabetic retinopathy and its mechanism of action. Mol Med Rep 2018; 18:385-390. [PMID: 29749515 DOI: 10.3892/mmr.2018.8988] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Accepted: 01/29/2018] [Indexed: 11/06/2022] Open
Affiliation(s)
- Junying Zhao
- Department of Ophthalmology, Dahua Hospital, Shanghai 200237, P.R. China
| | - Sha Gao
- Department of Ophthalmology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200025, P.R. China
| | - Yanji Zhu
- Department of Ophthalmology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200025, P.R. China
| | - Xi Shen
- Department of Ophthalmology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200025, P.R. China
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29
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Miranda DA, Krause WC, Cazenave-Gassiot A, Suzawa M, Escusa H, Foo JC, Shihadih DS, Stahl A, Fitch M, Nyangau E, Hellerstein M, Wenk MR, Silver DL, Ingraham HA. LRH-1 regulates hepatic lipid homeostasis and maintains arachidonoyl phospholipid pools critical for phospholipid diversity. JCI Insight 2018. [PMID: 29515023 DOI: 10.1172/jci.insight.96151] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Excess lipid accumulation is an early signature of nonalcoholic fatty liver disease (NAFLD). Although liver receptor homolog 1 (LRH-1) (encoded by NR5A2) is suppressed in human NAFLD, evidence linking this phospholipid-bound nuclear receptor to hepatic lipid metabolism is lacking. Here, we report an essential role for LRH-1 in hepatic lipid storage and phospholipid composition based on an acute hepatic KO of LRH-1 in adult mice (LRH-1AAV8-Cre mice). Indeed, LRH-1-deficient hepatocytes exhibited large cytosolic lipid droplets and increased triglycerides (TGs). LRH-1-deficient mice fed high-fat diet displayed macrovesicular steatosis, liver injury, and glucose intolerance, all of which were reversed or improved by expressing wild-type human LRH-1. While hepatic lipid synthesis decreased and lipid export remained unchanged in mutants, elevated circulating free fatty acid helped explain the lipid imbalance in LRH-1AAV8-Cre mice. Lipidomic and genomic analyses revealed that loss of LRH-1 disrupts hepatic phospholipid composition, leading to lowered arachidonoyl (AA) phospholipids due to repression of Elovl5 and Fads2, two critical genes in AA biosynthesis. Our findings reveal a role for the phospholipid sensor LRH-1 in maintaining adequate pools of hepatic AA phospholipids, further supporting the idea that phospholipid diversity is an important contributor to healthy hepatic lipid storage.
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Affiliation(s)
- Diego A Miranda
- Department of Cellular and Molecular Pharmacology, UCSF, San Francisco, California, USA
| | - William C Krause
- Department of Cellular and Molecular Pharmacology, UCSF, San Francisco, California, USA
| | - Amaury Cazenave-Gassiot
- Department of Biochemistry, Yong Loo Lin School of Medicine and Singapore Lipidomics Incubator, Life Sciences Institute, National University of Singapore, Singapore
| | - Miyuki Suzawa
- Department of Cellular and Molecular Pharmacology, UCSF, San Francisco, California, USA
| | - Hazel Escusa
- Department of Cellular and Molecular Pharmacology, UCSF, San Francisco, California, USA
| | - Juat Chin Foo
- Department of Biochemistry, Yong Loo Lin School of Medicine and Singapore Lipidomics Incubator, Life Sciences Institute, National University of Singapore, Singapore
| | - Diyala S Shihadih
- Department of Nutritional Sciences and Toxicology, University of California Berkeley, Berkeley, California, USA
| | - Andreas Stahl
- Department of Nutritional Sciences and Toxicology, University of California Berkeley, Berkeley, California, USA
| | - Mark Fitch
- Department of Nutritional Sciences and Toxicology, University of California Berkeley, Berkeley, California, USA
| | - Edna Nyangau
- Department of Nutritional Sciences and Toxicology, University of California Berkeley, Berkeley, California, USA
| | - Marc Hellerstein
- Department of Nutritional Sciences and Toxicology, University of California Berkeley, Berkeley, California, USA
| | - Markus R Wenk
- Department of Biochemistry, Yong Loo Lin School of Medicine and Singapore Lipidomics Incubator, Life Sciences Institute, National University of Singapore, Singapore
| | - David L Silver
- Signature Research Program in Cardiovascular and Metabolic Diseases, Duke-National University of Singapore, Singapore
| | - Holly A Ingraham
- Department of Cellular and Molecular Pharmacology, UCSF, San Francisco, California, USA
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30
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Murtaugh LC, MacDonald RJ. An inflammatory transcriptional switch. Nature 2018; 554:470-472. [DOI: 10.1038/d41586-018-01262-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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31
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Hamann BL, Blind RD. Nuclear phosphoinositide regulation of chromatin. J Cell Physiol 2017; 233:107-123. [PMID: 28256711 DOI: 10.1002/jcp.25886] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Accepted: 03/01/2017] [Indexed: 12/26/2022]
Abstract
Phospholipid signaling has clear connections to a wide array of cellular processes, particularly in gene expression and in controlling the chromatin biology of cells. However, most of the work elucidating how phospholipid signaling pathways contribute to cellular physiology have studied cytoplasmic membranes, while relatively little attention has been paid to the role of phospholipid signaling in the nucleus. Recent work from several labs has shown that nuclear phospholipid signaling can have important roles that are specific to this cellular compartment. This review focuses on the nuclear phospholipid functions and the activities of phospholipid signaling enzymes that regulate metazoan chromatin and gene expression. In particular, we highlight the roles that nuclear phosphoinositides play in several nuclear-driven physiological processes, such as differentiation, proliferation, and gene expression. Taken together, the recent discovery of several specifically nuclear phospholipid functions could have dramatic impact on our understanding of the fundamental mechanisms that enable tight control of cellular physiology.
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Affiliation(s)
- Bree L Hamann
- Division of Diabetes Endocrinology and Metabolism, Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Raymond D Blind
- Division of Diabetes Endocrinology and Metabolism, Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee.,Departments of Medicine, Biochemistry and Pharmacology, Division of Diabetes Endocrinology and Metabolism, The Vanderbilt Diabetes Research and Training Center and the Vanderbilt-Ingram Cancer Center, Nashville, Tennessee
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32
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Fletterick R. NR5A2 discovering compounds that block tumor growth in PDAC. J Surg Oncol 2017; 116:89-93. [PMID: 28445593 DOI: 10.1002/jso.24639] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Accepted: 03/22/2017] [Indexed: 11/08/2022]
Abstract
Pancreatic cancers depend on driver molecules, oncogene proteins such as RAS. NR5A2 protein is a transcription factor and either activates or inhibits transcription through actions at hundreds of enhancers. It has unusual properties with effects appearing in multiple signaling networks. NR5A2 is a pluripotency reprogramming factor in the class nuclear receptor. Its controlling hormone is PIP3. Experiments suggest NR5A2 activation drives PDAC and inhibitors blunt cancer cell proliferation.
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Affiliation(s)
- Robert Fletterick
- Department of Biochemistry, School of Medicine, UCSF, San Francisco, California
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33
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Yan L, Qiu J, Yao J. Downregulation of microRNA-30d promotes cell proliferation and invasion by targeting LRH-1 in colorectal carcinoma. Int J Mol Med 2017; 39:1371-1380. [PMID: 28440426 PMCID: PMC5428944 DOI: 10.3892/ijmm.2017.2958] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 04/03/2017] [Indexed: 12/13/2022] Open
Abstract
The aberrant expression of miR-30d has been reported in several types of human malignancies. However, its biological function in colorectal cancer (CRC) remains largely unknown. In this study, we identified that miR-30d was significantly downregulated in CRC tissues compared to that observed in normal controls as detected by RT-qPCR analysis. Downregulation of miR-30d was significantly associated with aggressive clinicopathological parameters including tumor differentiation, invasive depth, TNM stage, lymph node metastasis, distant metastasis, and poor prognosis. Furthermore, functional analysis revealed that overexpression of miR-30d significantly inhibited cell proliferation, caused cell cycle arrest at the G0/G1 phase, suppressed cell migration and invasion, induced cell apoptosis in vitro, and decreased tumor growth in a xenograft mouse model. Bioinformatic analysis and dual-luciferase reporter assay revealed that liver receptor homologue-1 (LRH-1) is a direct target of miR-30d in CRC cells. Rescue assay showed that LRH-1 overexpression could restore the inhibitory effect of miR-30d on CRC cells. In addition, miR-30d overexpression suppressed the activation of key components of the Wnt/β-catenin signaling pathway, β-catenin, c-Myc and cyclin D1, which contributed to the inhibition of CRC development. Thus, our findings suggest that miR-30d functions as a tumor suppressor against CRC development and miR-30d/LRH-1/Wnt signaling may be novel potential targets for CRC treatment.
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Affiliation(s)
- Likun Yan
- Department of General Surgery, Shaanxi Provincial People's Hospital, Xi'an, Shaanxi 710068, P.R. China
| | - Jian Qiu
- Department of General Surgery, Shaanxi Provincial People's Hospital, Xi'an, Shaanxi 710068, P.R. China
| | - Jianfeng Yao
- Department of General Surgery, Shaanxi Provincial People's Hospital, Xi'an, Shaanxi 710068, P.R. China
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34
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Crowder MK, Seacrist CD, Blind RD. Phospholipid regulation of the nuclear receptor superfamily. Adv Biol Regul 2016; 63:6-14. [PMID: 27838257 DOI: 10.1016/j.jbior.2016.10.006] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Revised: 10/24/2016] [Accepted: 10/26/2016] [Indexed: 11/27/2022]
Abstract
Nuclear receptors are ligand-activated transcription factors whose diverse biological functions are classically regulated by cholesterol-based small molecules. Over the past few decades, a growing body of evidence has demonstrated that phospholipids and other similar amphipathic molecules can also specifically bind and functionally regulate the activity of certain nuclear receptors, suggesting a critical role for these non-cholesterol-based molecules in transcriptional regulation. Phosphatidylcholines, phosphoinositides and sphingolipids are a few of the many phospholipid like molecules shown to quite specifically regulate nuclear receptors in mouse models, cell lines and in vitro. More recent evidence has also shown that certain nuclear receptors can "present" a bound phospholipid headgroup to key lipid signaling enzymes, which can then modify the phospholipid headgroup with very unique kinetic properties. Here, we review the broad array of phospholipid/nuclear receptor interactions, from the perspective of the chemical nature of the phospholipid, and the cellular abundance of the phospholipid. We also view the data in the light of well established paradigms for phospholipid mediated transcriptional regulation, as well as newer models of how phospholipids might effect transcription in the acute regulation of complex nuclear signaling pathways. Thus, this review provides novel insight into the new, non-membrane associated roles nuclear phospholipids play in regulating complex nuclear events, centered on the nuclear receptor superfamily of transcription factors.
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Affiliation(s)
- Mark K Crowder
- Department of Pharmacology, Vanderbilt University School of Medicine, USA
| | - Corey D Seacrist
- Department of Pharmacology, Vanderbilt University School of Medicine, USA
| | - Raymond D Blind
- Department of Pharmacology, Vanderbilt University School of Medicine, USA; Department of Biochemistry, Vanderbilt University School of Medicine, USA; Department of Medicine, Division of Diabetes, Endocrinology and Metabolism, Vanderbilt University School of Medicine, USA.
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35
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Mays SG, Okafor CD, Whitby RJ, Goswami D, Stec J, Flynn AR, Dugan MC, Jui NT, Griffin PR, Ortlund EA. Crystal Structures of the Nuclear Receptor, Liver Receptor Homolog 1, Bound to Synthetic Agonists. J Biol Chem 2016; 291:25281-25291. [PMID: 27694446 DOI: 10.1074/jbc.m116.753541] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Revised: 09/26/2016] [Indexed: 12/21/2022] Open
Abstract
Liver receptor homolog 1 (NR5A2, LRH-1) is an orphan nuclear hormone receptor that regulates diverse biological processes, including metabolism, proliferation, and the resolution of endoplasmic reticulum stress. Although preclinical and cellular studies demonstrate that LRH-1 has great potential as a therapeutic target for metabolic diseases and cancer, development of LRH-1 modulators has been difficult. Recently, systematic modifications to one of the few known chemical scaffolds capable of activating LRH-1 failed to improve efficacy substantially. Moreover, mechanisms through which LRH-1 is activated by synthetic ligands are entirely unknown. Here, we use x-ray crystallography and other structural methods to explore conformational changes and receptor-ligand interactions associated with LRH-1 activation by a set of related agonists. Unlike phospholipid LRH-1 ligands, these agonists bind deep in the pocket and do not interact with residues near the mouth nor do they expand the pocket like phospholipids. Unexpectedly, two closely related agonists with similar efficacies (GSK8470 and RJW100) exhibit completely different binding modes. The dramatic repositioning is influenced by a differential ability to establish stable face-to-face π-π-stacking with the LRH-1 residue His-390, as well as by a novel polar interaction mediated by the RJW100 hydroxyl group. The differing binding modes result in distinct mechanisms of action for the two agonists. Finally, we identify a network of conserved water molecules near the ligand-binding site that are important for activation by both agonists. This work reveals a previously unappreciated complexity associated with LRH-1 agonist development and offers insights into rational design strategies.
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Affiliation(s)
- Suzanne G Mays
- From the Department of Biochemistry, Emory University School of Medicine, and
| | - C Denise Okafor
- From the Department of Biochemistry, Emory University School of Medicine, and
| | - Richard J Whitby
- the School of Chemistry, University of Southampton, Southampton, Hants SO17 1BJ, United Kingdom, and
| | | | - Józef Stec
- the School of Chemistry, University of Southampton, Southampton, Hants SO17 1BJ, United Kingdom, and
| | - Autumn R Flynn
- the Department of Chemistry, Emory University, Atlanta, Georgia 30322
| | - Michael C Dugan
- the Department of Chemistry, Emory University, Atlanta, Georgia 30322
| | - Nathan T Jui
- the Department of Chemistry, Emory University, Atlanta, Georgia 30322
| | | | - Eric A Ortlund
- From the Department of Biochemistry, Emory University School of Medicine, and
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36
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de Jesus Cortez F, Suzawa M, Irvy S, Bruning JM, Sablin E, Jacobson MP, Fletterick RJ, Ingraham HA, England PM. Disulfide-Trapping Identifies a New, Effective Chemical Probe for Activating the Nuclear Receptor Human LRH-1 (NR5A2). PLoS One 2016; 11:e0159316. [PMID: 27467220 PMCID: PMC4965143 DOI: 10.1371/journal.pone.0159316] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Accepted: 06/30/2016] [Indexed: 11/21/2022] Open
Abstract
Conventional efforts relying on high-throughput physical and virtual screening of large compound libraries have failed to yield high-efficiency chemical probes for many of the 48 human nuclear receptors. Here, we investigated whether disulfide-trapping, an approach new to nuclear receptors, would provide effective lead compounds targeting human liver receptor homolog 1 (hLRH-1, NR5A2). Despite the fact that hLRH-1 contains a large ligand binding pocket and binds phospholipids with high affinity, existing synthetic hLRH-1 ligands are of limited utility due to poor solubility, low efficacy or significant off-target effects. Using disulfide-trapping, we identified a lead compound that conjugates with remarkably high-efficiency to a native cysteine residue (Cys346) lining the hydrophobic cavity in the ligand binding domain of hLRH-1. Guided by computational modeling and cellular assays, the lead compound was elaborated into ligands PME8 and PME9 that bind hLRH-1 reversibly (no cysteine reactivity) and increase hLRH-1 activity in cells. When compared with the existing hLRH-1 synthetic agonist RJW100, both PME8 and PME9 showed comparable induction of the LRH-1 dependent target gene CYP24A1 in human HepG2 cells, beginning as early as 3 h after drug treatment. The induction is specific as siRNA-mediated knock-down of hLRH-1 renders both PME8 and PME9 ineffective. These data show that PME8 and PME9 are potent activators of hLRH-1 and suggest that with further development this lead series may yield useful chemical probes for manipulating LRH-1 activity in vivo.
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Affiliation(s)
- Felipe de Jesus Cortez
- Department of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, California 94158, United States of America
| | - Miyuki Suzawa
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, California 94158, United States of America
| | - Sam Irvy
- Chemistry and Chemical Biology Graduate Program, University of California San Francisco, San Francisco, California 94158, United States of America
| | - John M. Bruning
- Pharmaceutical Sciences and Pharmacogenomics Graduate Program, University of California San Francisco, San Francisco, California 94158, United States of America
| | - Elena Sablin
- Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, California 94158, United States of America
| | - Matthew P. Jacobson
- Department of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, California 94158, United States of America
| | - Robert J. Fletterick
- Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, California 94158, United States of America
| | - Holly A. Ingraham
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, California 94158, United States of America
- * E-mail: (HAI); (PME)
| | - Pamela M. England
- Department of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, California 94158, United States of America
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, California 94158, United States of America
- * E-mail: (HAI); (PME)
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37
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Tribble EK, Ivanova PT, Grabon A, Alb JG, Faenza I, Cocco L, Brown HA, Bankaitis VA. Quantitative profiling of the endonuclear glycerophospholipidome of murine embryonic fibroblasts. J Lipid Res 2016; 57:1492-506. [PMID: 27256690 DOI: 10.1194/jlr.m068734] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Indexed: 01/18/2023] Open
Abstract
A reliable method for purifying envelope-stripped nuclei from immortalized murine embryonic fibroblasts (iMEFs) was established. Quantitative profiling of the glycerophospholipids (GPLs) in envelope-free iMEF nuclei yields several conclusions. First, we find the endonuclear glycerophospholipidome differs from that of bulk membranes, and phosphatidylcholine (PtdCho) and phosphatidylethanolamine species are the most abundant endonuclear GPLs by mass. By contrast, phosphatidylinositol (PtdIns) represents a minor species. We also find only a slight enrichment of saturated versus unsaturated GPL species in iMEF endonuclear fractions. Moreover, much lower values for GPL mass were measured in the iMEF nuclear matrix than those reported for envelope-stripped IMF-32 nuclei. The collective results indicate that the nuclear matrix in these cells is a GPL-poor environment where GPL occupies only approximately 0.1% of the total nuclear matrix volume. This value suggests GPL accommodation in this compartment can be satisfied by binding to resident proteins. Finally, we find no significant role for the PtdIns/PtdCho-transfer protein, PITPα, in shuttling PtdIns into the iMEF nuclear matrix.
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Affiliation(s)
- Emily K Tribble
- Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine, Chapel Hill, NC
| | - Pavlina T Ivanova
- Departments of Pharmacology and Biochemistry, Vanderbilt University School of Medicine, Vanderbilt Institute of Chemical Biology, Nashville, TN
| | - Aby Grabon
- Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine, Chapel Hill, NC Department of Molecular and Cellular Medicine, Texas A&M Health Science Center, College Station, TX
| | - James G Alb
- Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine, Chapel Hill, NC
| | - Irene Faenza
- Cellular Signaling Laboratory, Department of Biomedical Sciences, University of Bologna, Bologna, Italy
| | - Lucio Cocco
- Cellular Signaling Laboratory, Department of Biomedical Sciences, University of Bologna, Bologna, Italy
| | - H Alex Brown
- Departments of Pharmacology and Biochemistry, Vanderbilt University School of Medicine, Vanderbilt Institute of Chemical Biology, Nashville, TN
| | - Vytas A Bankaitis
- Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine, Chapel Hill, NC Department of Molecular and Cellular Medicine, Texas A&M Health Science Center, College Station, TX
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A polybasic motif in ErbB3-binding protein 1 (EBP1) has key functions in nucleolar localization and polyphosphoinositide interaction. Biochem J 2016; 473:2033-47. [PMID: 27118868 PMCID: PMC4941749 DOI: 10.1042/bcj20160274] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Accepted: 04/26/2016] [Indexed: 12/29/2022]
Abstract
We reveal the identification of a polybasic motif necessary for polyphosphoinositide interaction and nucleolar targeting of ErbB3 binding protein 1 (EBP1). EBP1 interacts directly with phosphatidylinositol(3,4,5)-triphosphate and their association is detected in the nucleolus, implying regulatory roles of nucleolar processes. Polyphosphoinositides (PPIns) are present in the nucleus where they participate in crucial nuclear processes, such as chromatin remodelling, transcription and mRNA processing. In a previous interactomics study, aimed to gain further insight into nuclear PPIns functions, we identified ErbB3 binding protein 1 (EBP1) as a potential nuclear PPIn-binding protein in a lipid pull-down screen. EBP1 is a ubiquitous and conserved protein, located in both the cytoplasm and nucleolus, and associated with cell proliferation and survival. In the present study, we show that EBP1 binds directly to several PPIns via two distinct PPIn-binding sites consisting of clusters of lysine residues and positioned at the N- and C-termini of the protein. Using interaction mutants, we show that the C-terminal PPIn-binding motif contributes the most to the localization of EBP1 in the nucleolus. Importantly, a K372N point mutation, located within the C-terminal motif and found in endometrial tumours, is sufficient to alter the nucleolar targeting of EBP1. Our study reveals also the presence of the class I phosphoinositide 3-kinase (PI3K) catalytic subunit p110β and its product PtdIns(3,4,5)P3 together with EBP1 in the nucleolus. Using NMR, we further demonstrate an association between EBP1 and PtdIns(3,4,5)P3 via both electrostatic and hydrophobic interactions. Taken together, these results show that EBP1 interacts directly with PPIns and associate with PtdIns(3,4,5)P3 in the nucleolus. The presence of p110β and PtdIns(3,4,5)P3 in the nucleolus indicates their potential role in regulating nucleolar processes, at least via EBP1.
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Tian Z, Guo F, Biswas S, Deng W. Rationale and Methodology of Reprogramming for Generation of Induced Pluripotent Stem Cells and Induced Neural Progenitor Cells. Int J Mol Sci 2016; 17:E594. [PMID: 27104529 PMCID: PMC4849048 DOI: 10.3390/ijms17040594] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Revised: 04/14/2016] [Accepted: 04/14/2016] [Indexed: 01/23/2023] Open
Abstract
Great progress has been made regarding the capabilities to modify somatic cell fate ever since the technology for generation of induced pluripotent stem cells (iPSCs) was discovered in 2006. Later, induced neural progenitor cells (iNPCs) were generated from mouse and human cells, bypassing some of the concerns and risks of using iPSCs in neuroscience applications. To overcome the limitation of viral vector induced reprogramming, bioactive small molecules (SM) have been explored to enhance the efficiency of reprogramming or even replace transcription factors (TFs), making the reprogrammed cells more amenable to clinical application. The chemical induced reprogramming process is a simple process from a technical perspective, but the choice of SM at each step is vital during the procedure. The mechanisms underlying cell transdifferentiation are still poorly understood, although, several experimental data and insights have indicated the rationale of cell reprogramming. The process begins with the forced expression of specific TFs or activation/inhibition of cell signaling pathways by bioactive chemicals in defined culture condition, which initiates the further reactivation of endogenous gene program and an optimal stoichiometric expression of the endogenous pluri- or multi-potency genes, and finally leads to the birth of reprogrammed cells such as iPSCs and iNPCs. In this review, we first outline the rationale and discuss the methodology of iPSCs and iNPCs in a stepwise manner; and then we also discuss the chemical-based reprogramming of iPSCs and iNPCs.
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Affiliation(s)
- Zuojun Tian
- Department of Neurology, the Institute of Guangzhou Respiratory Disease, State Key Laboratory of Respiratory Disease, the First Affiliated Hospital of Guangzhou Medical University, Guangzhou 510120, China.
- Department of Biochemistry and Molecular Medicine, School of Medicine, University of California, Davis, CA 95817, USA.
- Institute for Pediatric Regenerative Medicine, Shriners Hospitals for Children, Sacramento, CA 95817, USA.
| | - Fuzheng Guo
- Institute for Pediatric Regenerative Medicine, Shriners Hospitals for Children, Sacramento, CA 95817, USA.
| | - Sangita Biswas
- Department of Biochemistry and Molecular Medicine, School of Medicine, University of California, Davis, CA 95817, USA.
- Institute for Pediatric Regenerative Medicine, Shriners Hospitals for Children, Sacramento, CA 95817, USA.
| | - Wenbin Deng
- Department of Biochemistry and Molecular Medicine, School of Medicine, University of California, Davis, CA 95817, USA.
- Institute for Pediatric Regenerative Medicine, Shriners Hospitals for Children, Sacramento, CA 95817, USA.
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Tools for visualization of phosphoinositides in the cell nucleus. Histochem Cell Biol 2016; 145:485-96. [DOI: 10.1007/s00418-016-1409-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/14/2016] [Indexed: 01/09/2023]
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