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Wang C, Zhang X, Wu K, Liu S, Li X, Zhu C, Xiao Y, Fang Z, Liu J. Two Zn 2Cys 6-type transcription factors respond to aromatic compounds and regulate the expression of laccases in the white-rot fungus Trametes hirsuta. Appl Environ Microbiol 2024; 90:e0054524. [PMID: 38899887 PMCID: PMC11267944 DOI: 10.1128/aem.00545-24] [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: 03/22/2024] [Accepted: 05/29/2024] [Indexed: 06/21/2024] Open
Abstract
White-rot fungi differentially express laccases when they encounter aromatic compounds. However, the underlying mechanisms are still being explored. Here, proteomics analysis revealed that in addition to increased laccase activity, proteins involved in sphingolipid metabolism and toluene degradation as well as some cytochrome P450s (CYP450s) were differentially expressed and significantly enriched during 48 h of o-toluidine exposure, in Trametes hirsuta AH28-2. Two Zn2Cys6-type transcription factors (TFs), TH8421 and TH4300, were upregulated. Bioinformatics docking and isothermal titration calorimetry assays showed that each of them could bind directly to o-toluidine and another aromatic monomer, guaiacol. Binding to aromatic compounds promoted the formation of TH8421/TH4300 heterodimers. TH8421 and TH4300 silencing in T. hirsuta AH28-2 led to decreased transcriptional levels and activities of LacA and LacB upon o-toluidine and guaiacol exposure. EMSA and ChIP-qPCR analysis further showed that TH8421 and TH4300 bound directly with the promoter regions of lacA and lacB containing CGG or CCG motifs. Furthermore, the two TFs were involved in direct and positive regulation of the transcription of some CYP450s. Together, TH8421 and TH4300, two key regulators found in T. hirsuta AH28-2, function as heterodimers to simultaneously trigger the expression of downstream laccases and intracellular enzymes. Monomeric aromatic compounds act as ligands to promote heterodimer formation and enhance the transcriptional activities of the two TFs.IMPORTANCEWhite-rot fungi differentially express laccase isoenzymes when exposed to aromatic compounds. Clarification of the molecular mechanisms underlying differential laccase expression is essential to elucidate how white-rot fungi respond to the environment. Our study shows that two Zn2Cys6-type transcription factors form heterodimers, interact with the promoters of laccase genes, and positively regulate laccase transcription in Trametes hirsuta AH28-2. Aromatic monomer addition induces faster heterodimer formation and rate of activity. These findings not only identify two new transcription factors involved in fungal laccase transcription but also deepen our understanding of the mechanisms underlying the response to aromatics exposure in white-rot fungi.
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Affiliation(s)
- Chenkai Wang
- School of Life Sciences, Anhui University, Hefei, Anhui, China
- Anhui Key Laboratory of Modern Biomanufacturing, Hefei, Anhui, China
- Anhui Provincial Engineering Technology Research Center of Microorganisms and Biocatalysis, Hefei, Anhui, China
| | - Xinlei Zhang
- School of Life Sciences, Anhui University, Hefei, Anhui, China
- Anhui Key Laboratory of Modern Biomanufacturing, Hefei, Anhui, China
- Anhui Provincial Engineering Technology Research Center of Microorganisms and Biocatalysis, Hefei, Anhui, China
| | - Kun Wu
- School of Life Sciences, Anhui University, Hefei, Anhui, China
- Anhui Key Laboratory of Modern Biomanufacturing, Hefei, Anhui, China
- Anhui Provincial Engineering Technology Research Center of Microorganisms and Biocatalysis, Hefei, Anhui, China
| | - Shenglong Liu
- School of Life Sciences, Anhui University, Hefei, Anhui, China
- Anhui Key Laboratory of Modern Biomanufacturing, Hefei, Anhui, China
- Anhui Provincial Engineering Technology Research Center of Microorganisms and Biocatalysis, Hefei, Anhui, China
| | - Xiang Li
- School of Life Sciences, Anhui University, Hefei, Anhui, China
| | - Chaona Zhu
- School of Life Sciences, Anhui University, Hefei, Anhui, China
| | - Yazhong Xiao
- School of Life Sciences, Anhui University, Hefei, Anhui, China
- Anhui Key Laboratory of Modern Biomanufacturing, Hefei, Anhui, China
- Anhui Provincial Engineering Technology Research Center of Microorganisms and Biocatalysis, Hefei, Anhui, China
| | - Zemin Fang
- School of Life Sciences, Anhui University, Hefei, Anhui, China
- Anhui Key Laboratory of Modern Biomanufacturing, Hefei, Anhui, China
- Anhui Provincial Engineering Technology Research Center of Microorganisms and Biocatalysis, Hefei, Anhui, China
| | - Juanjuan Liu
- School of Life Sciences, Anhui University, Hefei, Anhui, China
- Anhui Key Laboratory of Modern Biomanufacturing, Hefei, Anhui, China
- Anhui Provincial Engineering Technology Research Center of Microorganisms and Biocatalysis, Hefei, Anhui, China
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A structural signature motif enlightens the origin and diversification of nuclear receptors. PLoS Genet 2021; 17:e1009492. [PMID: 33882063 PMCID: PMC8092661 DOI: 10.1371/journal.pgen.1009492] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 05/03/2021] [Accepted: 03/15/2021] [Indexed: 12/11/2022] Open
Abstract
Nuclear receptors are ligand-activated transcription factors that modulate gene regulatory networks from embryonic development to adult physiology and thus represent major targets for clinical interventions in many diseases. Most nuclear receptors function either as homodimers or as heterodimers. The dimerization is crucial for gene regulation by nuclear receptors, by extending the repertoire of binding sites in the promoters or the enhancers of target genes via combinatorial interactions. Here, we focused our attention on an unusual structural variation of the α-helix, called π-turn that is present in helix H7 of the ligand-binding domain of RXR and HNF4. By tracing back the complex evolutionary history of the π-turn, we demonstrate that it was present ancestrally and then independently lost in several nuclear receptor lineages. Importantly, the evolutionary history of the π-turn motif is parallel to the evolutionary diversification of the nuclear receptor dimerization ability from ancestral homodimers to derived heterodimers. We then carried out structural and biophysical analyses, in particular through point mutation studies of key RXR signature residues and showed that this motif plays a critical role in the network of interactions stabilizing homodimers. We further showed that the π-turn was instrumental in allowing a flexible heterodimeric interface of RXR in order to accommodate multiple interfaces with numerous partners and critical for the emergence of high affinity receptors. Altogether, our work allows to identify a functional role for the π-turn in oligomerization of nuclear receptors and reveals how this motif is linked to the emergence of a critical biological function. We conclude that the π-turn can be viewed as a structural exaptation that has contributed to enlarging the functional repertoire of nuclear receptors. The origin of novelties is a central topic in evolutionary biology. A fundamental question is how organisms constrained by natural selection can divert from existing schemes to set up novel structures or pathways. Among the most important strategies are exaptations, which represent pre-adaptation strategies. Many examples exist in biology, at both morphological and molecular levels, such as the one reported here that focuses on an unusual structural feature called the π-turn. It is found in the structure of the most ancestral nuclear receptors RXR and HNF4. The analyses trace back the complex evolutionary history of the π-turn to more than 500 million years ago, before the Cambrian explosion and show that this feature was essential for the heterodimerization capacity of RXR. Nuclear receptor lineages that emerged later in evolution lost the π-turn. We demonstrate here that this loss in nuclear receptors that heterodimerize with RXR was critical for the emergence of high affinity receptors, such as the vitamin D and the thyroid hormone receptors. On the other hand, the conserved π-turn in RXR allowed it to accommodate multiple heterodimer interfaces with numerous partners. This structural exaptation allowed for the remarkable diversification of nuclear receptors.
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Shao M, Lu L, Wang Q, Ma L, Tian X, Li C, Li C, Guo D, Wang Q, Wang W, Wang Y. The multi-faceted role of retinoid X receptor in cardiovascular diseases. Biomed Pharmacother 2021; 137:111264. [PMID: 33761589 DOI: 10.1016/j.biopha.2021.111264] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 01/04/2021] [Accepted: 01/07/2021] [Indexed: 01/14/2023] Open
Abstract
Retinoid X receptors (RXRs) are members of ligand-dependent transcription factors whose effects on a diversity of cellular processes, including cellular proliferation, the immune response, and lipid and glucose metabolism. Knock out of RXRα causes a hypoplasia of the myocardium which is lethal during fetal life. In addition, the heart maintains a well-orchestrated balances in utilizing fatty acids (FAs) and other substrates to meet the high energy requirements. As the master transcriptional regulators of lipid metabolism, RXRs become particularly important for the energy needs of the heart. Accumulating evidence suggested that RXRs may exert direct beneficial effects in the heart both through heterodimerization with other nuclear receptors (NRs) and homodimerization, thus standing as suitable targets for treating in cardiovascular diseases. Although compounds that target RXRs are promising drugs, their use is limited by toxicity. A better understanding of the structural biology of RXRs in cardiovascular disease should enable the rational design of more selective nuclear receptor modulators to overcome these problems. Here, this review summarizes a brief overview of RXRs structure and versatility of RXR action in the control of cardiovascular diseases. And we also discussed the therapeutic potential of RXR ligand.
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Affiliation(s)
- Mingyan Shao
- School of Life Science, Beijing University of Chinese Medicine, Beijing, 100029, China
| | - Linghui Lu
- College of Traditional Chinese Medicine, Beijing University of Chinese Medicine, Beijing, 100029, China
| | - Qian Wang
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing, 100191, China
| | - Lin Ma
- School of Life Science, Beijing University of Chinese Medicine, Beijing, 100029, China
| | - Xue Tian
- School of Life Science, Beijing University of Chinese Medicine, Beijing, 100029, China
| | - Changxiang Li
- College of Traditional Chinese Medicine, Beijing University of Chinese Medicine, Beijing, 100029, China
| | - Chun Li
- Modern Research Center of Traditional Chinese Medicine, School of Traditional Chinese Material Medica, Beijing University of Chinese Medicine, Beijing, 100029, China
| | - Dongqing Guo
- School of Life Science, Beijing University of Chinese Medicine, Beijing, 100029, China
| | - Qiyan Wang
- School of Life Science, Beijing University of Chinese Medicine, Beijing, 100029, China
| | - Wei Wang
- School of Life Science, Beijing University of Chinese Medicine, Beijing, 100029, China.
| | - Yong Wang
- School of Life Science, Beijing University of Chinese Medicine, Beijing, 100029, China; College of Traditional Chinese Medicine, Beijing University of Chinese Medicine, Beijing, 100029, China.
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Miglioli A, Canesi L, Gomes IDL, Schubert M, Dumollard R. Nuclear Receptors and Development of Marine Invertebrates. Genes (Basel) 2021; 12:genes12010083. [PMID: 33440651 PMCID: PMC7827873 DOI: 10.3390/genes12010083] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 12/31/2020] [Accepted: 01/04/2021] [Indexed: 12/12/2022] Open
Abstract
Nuclear Receptors (NRs) are a superfamily of transcription factors specific to metazoans that have the unique ability to directly translate the message of a signaling molecule into a transcriptional response. In vertebrates, NRs are pivotal players in countless processes of both embryonic and adult physiology, with embryonic development being one of the most dynamic periods of NR activity. Accumulating evidence suggests that NR signaling is also a major regulator of development in marine invertebrates, although ligands and transactivation dynamics are not necessarily conserved with respect to vertebrates. The explosion of genome sequencing projects and the interpretation of the resulting data in a phylogenetic context allowed significant progress toward an understanding of NR superfamily evolution, both in terms of molecular activities and developmental functions. In this context, marine invertebrates have been crucial for characterizing the ancestral states of NR-ligand interactions, further strengthening the importance of these organisms in the field of evolutionary developmental biology.
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Affiliation(s)
- Angelica Miglioli
- Laboratoire de Biologie du Développement de Villefranche-sur-Mer (LBDV), Institut de la Mer de Villefranche, Sorbonne Université, CNRS, 181 Chemin du Lazaret, 06230 Villefranche-sur-Mer, France; (A.M.); (I.D.L.G.); (M.S.)
- Dipartimento di Scienze della Terra, dell’Ambiente e della Vita (DISTAV), Università degli Studi di Genova, Corso Europa 26, 16132 Genova, Italy;
| | - Laura Canesi
- Dipartimento di Scienze della Terra, dell’Ambiente e della Vita (DISTAV), Università degli Studi di Genova, Corso Europa 26, 16132 Genova, Italy;
| | - Isa D. L. Gomes
- Laboratoire de Biologie du Développement de Villefranche-sur-Mer (LBDV), Institut de la Mer de Villefranche, Sorbonne Université, CNRS, 181 Chemin du Lazaret, 06230 Villefranche-sur-Mer, France; (A.M.); (I.D.L.G.); (M.S.)
| | - Michael Schubert
- Laboratoire de Biologie du Développement de Villefranche-sur-Mer (LBDV), Institut de la Mer de Villefranche, Sorbonne Université, CNRS, 181 Chemin du Lazaret, 06230 Villefranche-sur-Mer, France; (A.M.); (I.D.L.G.); (M.S.)
| | - Rémi Dumollard
- Laboratoire de Biologie du Développement de Villefranche-sur-Mer (LBDV), Institut de la Mer de Villefranche, Sorbonne Université, CNRS, 181 Chemin du Lazaret, 06230 Villefranche-sur-Mer, France; (A.M.); (I.D.L.G.); (M.S.)
- Correspondence:
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Yang M, Chen J, Wei W. Dimerization of glucocorticoid receptors and its role in inflammation and immune responses. Pharmacol Res 2020; 166:105334. [PMID: 33276107 DOI: 10.1016/j.phrs.2020.105334] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 11/18/2020] [Accepted: 11/27/2020] [Indexed: 12/19/2022]
Abstract
Glucocorticoids (GCs) plays an irreplaceable role in inflammation and immune responses, fat metabolism and sugar metabolism, it is often used for the treatment of asthma, rheumatoid arthritis and allergic rhinitis clinically, but long-term or high-dose use will produce adverse drug reactions (ADRs). Its biological action is mediated by glucocorticoid receptors (GRs), of which the oligomerization state is closely related to the target gene of which the GRs act. A leading hypothesis is that the beneficial anti-inflammatory effects of GCs occur through the transrepression mechanism mediated by GR monomers, while ADRs may be dependent on the transactivation mechanism mediated by GR dimers. However, in recent years, multiple studies have shown that the transactivation and transrepression functions of the GR dimer also confer anti-inflammatory effects. Furthermore, some studies have shown that some selective glucocorticoid receptor agonists and modulators (SEGRAMs) have good separation characteristics (i.e., preferentially mediate the transrepression of proinflammatory genes or preferentially activate anti-inflammatory target genes). This article reviewed the formation of GR dimers, the role of GR dimers in the inflammation and immune responses, and the progress of SEGRAMs to provide novel ideas for further understanding the anti-inflammatory mechanism of GR and the development of SEGRAMs.
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Affiliation(s)
- Mei Yang
- Institute of Clinical Pharmacology, Anhui Medical University, Key Laboratory of Anti-Inflammatory and Immune Medicine, Ministry of Education, Anhui Collaborative Innovation Center of Anti-Inflammatory and Immune Medicine, Meishan Road 81, Hefei, 230032, China
| | - Jingyu Chen
- Institute of Clinical Pharmacology, Anhui Medical University, Key Laboratory of Anti-Inflammatory and Immune Medicine, Ministry of Education, Anhui Collaborative Innovation Center of Anti-Inflammatory and Immune Medicine, Meishan Road 81, Hefei, 230032, China.
| | - Wei Wei
- Institute of Clinical Pharmacology, Anhui Medical University, Key Laboratory of Anti-Inflammatory and Immune Medicine, Ministry of Education, Anhui Collaborative Innovation Center of Anti-Inflammatory and Immune Medicine, Meishan Road 81, Hefei, 230032, China.
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6
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Kalaskar VK, Alur RP, Li LK, Thomas JW, Sergeev YV, Blain D, Hufnagel RB, Cogliati T, Brooks BP. High-throughput custom capture sequencing identifies novel mutations in coloboma-associated genes: Mutation in DNA-binding domain of retinoic acid receptor beta affects nuclear localization causing ocular coloboma. Hum Mutat 2019; 41:678-695. [PMID: 31816153 PMCID: PMC7027867 DOI: 10.1002/humu.23954] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 10/04/2019] [Accepted: 11/09/2019] [Indexed: 12/11/2022]
Abstract
Uveal coloboma is a potentially blinding congenital ocular malformation caused by the failure of optic fissure closure during the fifth week of human gestation. We performed custom capture high‐throughput screening of 38 known coloboma‐associated genes in 66 families. Suspected causative novel variants were identified in TFAP2A and CHD7, as well as two previously reported variants of uncertain significance in RARB and BMP7. The variant in RARB, unlike previously reported disease mutations in the ligand‐binding domain, was a missense change in the highly conserved DNA‐binding domain predicted to affect the protein's DNA‐binding ability. In vitro studies revealed lower steady‐state protein levels, reduced transcriptional activity, and incomplete nuclear localization of the mutant RARB protein compared with wild‐type. Zebrafish studies showed that human RARB messenger RNA partially reduced the ocular phenotype caused by morpholino knockdown of rarga gene, a zebrafish homolog of human RARB. Our study indicates that sequence alterations in known coloboma genes account for a small percentage of coloboma cases and that mutations in the RARB DNA‐binding domain could result in human disease.
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Affiliation(s)
- Vijay K Kalaskar
- Pediatric, Developmental & Genetic Ophthalmology Section, Ophthalmic Genetics and Visual Function Branch (OGVFB), National Eye Institute (NEI), National Institutes of Health (NIH), Bethesda, Maryland
| | - Ramakrishna P Alur
- Pediatric, Developmental & Genetic Ophthalmology Section, Ophthalmic Genetics and Visual Function Branch (OGVFB), National Eye Institute (NEI), National Institutes of Health (NIH), Bethesda, Maryland
| | - LeeAnn K Li
- Pediatric, Developmental & Genetic Ophthalmology Section, Ophthalmic Genetics and Visual Function Branch (OGVFB), National Eye Institute (NEI), National Institutes of Health (NIH), Bethesda, Maryland
| | - James W Thomas
- National Institutes of Health Intramural Sequencing Center, National Human Genome Research Institute, NIH, Bethesda, Maryland
| | - Yuri V Sergeev
- Protein Biochemistry and Molecular Modeling Group, OGVFB, NEI, NIH, Bethesda, Maryland
| | - Delphine Blain
- Ophthalmic Clinical Genetics Section, OGVFB, NEI, NIH, Bethesda, Maryland
| | - Robert B Hufnagel
- Medical Genetics and Ophthalmic Genomics Unit, OGVFB, NEI, NIH, Bethesda, Maryland
| | - Tiziana Cogliati
- Pediatric, Developmental & Genetic Ophthalmology Section, Ophthalmic Genetics and Visual Function Branch (OGVFB), National Eye Institute (NEI), National Institutes of Health (NIH), Bethesda, Maryland
| | - Brian P Brooks
- Pediatric, Developmental & Genetic Ophthalmology Section, Ophthalmic Genetics and Visual Function Branch (OGVFB), National Eye Institute (NEI), National Institutes of Health (NIH), Bethesda, Maryland.,Ophthalmic Clinical Genetics Section, OGVFB, NEI, NIH, Bethesda, Maryland
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Singh P, Tung SP, Han EH, Lee IK, Chi YI. Dimerization defective MODY mutations of hepatocyte nuclear factor 4α. Mutat Res 2019; 814:1-6. [PMID: 30648609 DOI: 10.1016/j.mrfmmm.2019.01.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 11/13/2018] [Accepted: 01/08/2019] [Indexed: 10/27/2022]
Abstract
HNF4α is a culprit gene product for a monogenic and dominantly-inherited form of diabetes, referred to as MODY1 (Maturity Onset Diabetes of the Young type 1). Reduced HNF4α activities have been linked to impaired insulin secretion and β-cell function. Numerous mutations have been identified from the patients and they have been instructive as to the individual residue's role in protein structure-function and dysfunction. As a member of the nuclear receptor (NR) superfamily, HNF4α is made of characteristic modular domains and it functions exclusively as a homodimer despite its sequence homology to RXR, a common heterodimer partner of non-steroidal NRs. Transcription factors commonly dimerize to enhance their molecular functions mainly by facilitating the recognition of double helix target DNAs that display an intrinsic pseudo-2-fold symmetry and the recruitment of the remainder of the main transcriptional machinery. HNF4α is no exception and its dimerization is maintained by the ligand binding domain (LBD) mainly through the leucine-zipper-like interactions at the stalk of two interacting helices. Although many MODY1 mutations have been previously characterized, including DNA binding disruptors, ligand binding disruptors, coactivator binding disruptors, and protein stability disruptors, protein dimerization disruptors have not been formally reported. In this report, we present a set of data for the two MODY1 mutations found right at the dimerization interface (L332 P and L328del mutations) which clearly exhibit the disruptive effects of directly affecting dimerization, protein stability, and transcriptional activities. These data reinforced the fact that MODY mutations are loss-of-function mutations and HNF4α dimerization is essential for its optimal function and normal physiology.
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Affiliation(s)
- Puja Singh
- Section of Structural Biology, Hormel Institute, University of Minnesota, Austin, MN, United States
| | - Shu-Ping Tung
- Section of Structural Biology, Hormel Institute, University of Minnesota, Austin, MN, United States
| | - Eun Hee Han
- Drug & Disease Target Group, Division of Life Science, Korea Basic Science Institute, Cheongju, Republic of Korea
| | - In-Kyu Lee
- Department of Internal Medicine, School of Medicine, Kyungpook National University, Kyungpook National University Hospital, Daegu, Republic of Korea
| | - Young-In Chi
- Section of Structural Biology, Hormel Institute, University of Minnesota, Austin, MN, United States.
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Bianchetti L, Wassmer B, Defosset A, Smertina A, Tiberti ML, Stote RH, Dejaegere A. Alternative dimerization interfaces in the glucocorticoid receptor-α ligand binding domain. Biochim Biophys Acta Gen Subj 2018; 1862:1810-1825. [PMID: 29723544 DOI: 10.1016/j.bbagen.2018.04.022] [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: 01/12/2018] [Revised: 04/19/2018] [Accepted: 04/27/2018] [Indexed: 10/17/2022]
Abstract
BACKGROUND Nuclear hormone receptors (NRs) constitute a large family of multi-domain ligand-activated transcription factors. Dimerization is essential for their regulation, and both DNA binding domain (DBD) and ligand binding domain (LBD) are implicated in dimerization. Intriguingly, the glucocorticoid receptor-α (GRα) presents a DBD dimeric architecture similar to that of the homologous estrogen receptor-α (ERα), but an atypical dimeric architecture for the LBD. The physiological relevance of the proposed GRα LBD dimer is a subject of debate. METHODS We analyzed all GRα LBD homodimers observed in crystals using an energetic analysis based on the PISA and on the MM/PBSA methods and a sequence conservation analysis, using the ERα LBD dimer as a reference point. RESULTS Several dimeric assemblies were observed for GRα LBD. The assembly generally taken to be physiologically relevant showed weak binding free energy and no significant residue conservation at the contact interface, while an alternative homodimer mediated by both helix 9 and C-terminal residues showed significant binding free energy and residue conservation. However, none of the GRα LBD assemblies found in crystals are as stable or conserved as the canonical ERα LBD dimer. GRα C-terminal sequence (F-domain) forms a steric obstacle to the canonical dimer assembly in all available structures. CONCLUSIONS Our analysis calls for a re-examination of the currently accepted GRα homodimer structure and experimental investigations of the alternative architectures. GENERAL SIGNIFICANCE This work questions the validity of the currently accepted architecture. This has implications for interpreting physiological data and for therapeutic design pertaining to glucocorticoid research.
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Affiliation(s)
- Laurent Bianchetti
- Biocomputing and Molecular Modelling Laboratory, Integrated Structural Biology Department, Institute of Genetics and Molecular and Cellular Biology (IGBMC), CNRS UMR 7104 - Inserm U1258 - Université de Strasbourg, 1 rue Laurent Fries, 67404 Illkirch, France
| | - Bianca Wassmer
- Biocomputing and Molecular Modelling Laboratory, Integrated Structural Biology Department, Institute of Genetics and Molecular and Cellular Biology (IGBMC), CNRS UMR 7104 - Inserm U1258 - Université de Strasbourg, 1 rue Laurent Fries, 67404 Illkirch, France
| | - Audrey Defosset
- Biocomputing and Molecular Modelling Laboratory, Integrated Structural Biology Department, Institute of Genetics and Molecular and Cellular Biology (IGBMC), CNRS UMR 7104 - Inserm U1258 - Université de Strasbourg, 1 rue Laurent Fries, 67404 Illkirch, France
| | - Anna Smertina
- Biocomputing and Molecular Modelling Laboratory, Integrated Structural Biology Department, Institute of Genetics and Molecular and Cellular Biology (IGBMC), CNRS UMR 7104 - Inserm U1258 - Université de Strasbourg, 1 rue Laurent Fries, 67404 Illkirch, France
| | - Marion L Tiberti
- Biocomputing and Molecular Modelling Laboratory, Integrated Structural Biology Department, Institute of Genetics and Molecular and Cellular Biology (IGBMC), CNRS UMR 7104 - Inserm U1258 - Université de Strasbourg, 1 rue Laurent Fries, 67404 Illkirch, France
| | - Roland H Stote
- Biocomputing and Molecular Modelling Laboratory, Integrated Structural Biology Department, Institute of Genetics and Molecular and Cellular Biology (IGBMC), CNRS UMR 7104 - Inserm U1258 - Université de Strasbourg, 1 rue Laurent Fries, 67404 Illkirch, France
| | - Annick Dejaegere
- Biocomputing and Molecular Modelling Laboratory, Integrated Structural Biology Department, Institute of Genetics and Molecular and Cellular Biology (IGBMC), CNRS UMR 7104 - Inserm U1258 - Université de Strasbourg, 1 rue Laurent Fries, 67404 Illkirch, France.
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9
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Hope CM, Rebay I, Reinitz J. DNA Occupancy of Polymerizing Transcription Factors: A Chemical Model of the ETS Family Factor Yan. Biophys J 2017; 112:180-192. [PMID: 28076810 DOI: 10.1016/j.bpj.2016.11.901] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 10/18/2016] [Accepted: 11/11/2016] [Indexed: 11/28/2022] Open
Abstract
Transcription factors use both protein-DNA and protein-protein interactions to assemble appropriate complexes to regulate gene expression. Although most transcription factors operate as monomers or dimers, a few, including the E26 transformation-specific family repressors Drosophila melanogaster Yan and its human homolog TEL/ETV6, can polymerize. Although polymerization is required for both the normal and oncogenic function of Yan and TEL/ETV6, the mechanisms by which it influences the recruitment, organization, and stability of transcriptional complexes remain poorly understood. Further, a quantitative description of the DNA occupancy of a polymerizing transcription factor is lacking, and such a description would have broader applications to the conceptually related area of polymerizing chromatin regulators. To expand the theoretical basis for understanding how the oligomeric state of a transcriptional regulator influences its chromatin occupancy and function, we leveraged the extensive biochemical characterization of E26 transformation-specific factors to develop a mathematical model of Yan occupancy at chemical equilibrium. We find that spreading condensation from a specific binding site can take place in a path-independent manner given reasonable values of the free energies of specific and non-specific DNA binding and protein-protein cooperativity. Our calculations show that polymerization confers upon a transcription factor the unique ability to extend occupancy across DNA regions far from specific binding sites. In contrast, dimerization promotes recruitment to clustered binding sites and maximizes discrimination between specific and non-specific sites. We speculate that the association with non-specific DNA afforded by polymerization may enable regulatory behaviors that are well-suited to transcriptional repressors but perhaps incompatible with precise activation.
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Affiliation(s)
- C Matthew Hope
- Department of Biochemistry and Molecular Biophysics, The University of Chicago, Chicago, Illinois
| | - Ilaria Rebay
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, Illinois; Ben May Department for Cancer Research, The University of Chicago, Chicago, Illinois.
| | - John Reinitz
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, Illinois; Department of Ecology and Evolution, The University of Chicago, Chicago, Illinois; Department of Statistics, The University of Chicago, Chicago, Illinois.
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Sharma V, Pandey AK, Kumar A, Misra S, Gupta HPK, Gupta S, Singh A, Buehner NA, Ravi Ram K. Functional male accessory glands and fertility in Drosophila require novel ecdysone receptor. PLoS Genet 2017; 13:e1006788. [PMID: 28493870 PMCID: PMC5444863 DOI: 10.1371/journal.pgen.1006788] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Revised: 05/25/2017] [Accepted: 05/01/2017] [Indexed: 12/17/2022] Open
Abstract
In many insects, the accessory gland, a secretory tissue of the male reproductive system, is essential for male fertility. Male accessory gland is the major source of proteinaceous secretions, collectively called as seminal proteins (or accessory gland proteins), which upon transfer, manipulate the physiology and behavior of mated females. Insect hormones such as ecdysteroids and juvenoids play a key role in accessory gland development and protein synthesis but little is known about underlying molecular players and their mechanism of action. Therefore, in the present study, we examined the roles of hormone-dependent transcription factors (Nuclear Receptors), in accessory gland development, function and male fertility of a genetically tractable insect model, Drosophila melanogaster. First, we carried out an RNAi screen involving 19 hormone receptors, individually and specifically, in a male reproductive tissue (accessory gland) for their requirement in Drosophila male fertility. Subsequently, by using independent RNAi/ dominant negative forms, we show that Ecdysone Receptor (EcR) is essential for male fertility due to its requirement in the normal development of accessory glands in Drosophila: EcR depleted glands fail to make seminal proteins and have dying cells. Further, our data point to a novel ecdysone receptor that does not include Ultraspiracle but is probably comprised of EcR isoforms in Drosophila male accessory glands. Our data suggest that this novel ecdysone receptor might act downstream of homeodomain transcription factor paired (prd) in the male accessory gland. Overall, the study suggests novel ecdysone receptor as an important player in the hormonal regulation of seminal protein production and insect male fertility. Insects are the major contributors to biodiversity and have economic, agricultural and health importance. This unparalleled abundance of insects, in part, can be attributed to their high reproductive potential. In many insects, proteins derived from the accessory gland, the secretory tissue of male reproductive system, are critical for fertility. The production of these accessory gland proteins is regulated by insect hormones but the underlying mechanisms/molecular players remain poorly understood. Elucidation of the same has potential applications in designing pest control management strategies and to understand the effect of environmental chemicals on reproduction. In view of this, we analyzed the role, if any, of various insect hormone receptors in development and function of the male accessory gland in a genetically tractable insect model, Drosophila melanogaster. Here, we report the involvement of Ecdysone receptor (EcR with novel composition) in Drosophila male fertility. We show that the depletion of this receptor causes cell death in male accessory glands, which fail to produce seminal fluid proteins leading to sterility/sub-fertility of Drosophila males. These findings will find potential applications in designing insect pest control strategies.
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Affiliation(s)
- Vandana Sharma
- Embryotoxicology Laboratory, Environmental Toxicology Group, CSIR- Indian Institute of Toxicology Research (CSIR-IITR), Vishvigyan Bhavan, 31, Mahatma Gandhi Marg, Lucknow, Uttar Pradesh, India
- Academy of Scientific and Innovative Research (AcSIR), CSIR-IITR Campus, Lucknow. Uttar Pradesh, India
| | - Anuj K. Pandey
- Embryotoxicology Laboratory, Environmental Toxicology Group, CSIR- Indian Institute of Toxicology Research (CSIR-IITR), Vishvigyan Bhavan, 31, Mahatma Gandhi Marg, Lucknow, Uttar Pradesh, India
| | - Ajay Kumar
- Embryotoxicology Laboratory, Environmental Toxicology Group, CSIR- Indian Institute of Toxicology Research (CSIR-IITR), Vishvigyan Bhavan, 31, Mahatma Gandhi Marg, Lucknow, Uttar Pradesh, India
- Academy of Scientific and Innovative Research (AcSIR), CSIR-IITR Campus, Lucknow. Uttar Pradesh, India
| | - Snigdha Misra
- Embryotoxicology Laboratory, Environmental Toxicology Group, CSIR- Indian Institute of Toxicology Research (CSIR-IITR), Vishvigyan Bhavan, 31, Mahatma Gandhi Marg, Lucknow, Uttar Pradesh, India
- Academy of Scientific and Innovative Research (AcSIR), CSIR-IITR Campus, Lucknow. Uttar Pradesh, India
| | - Himanshu P. K. Gupta
- Embryotoxicology Laboratory, Environmental Toxicology Group, CSIR- Indian Institute of Toxicology Research (CSIR-IITR), Vishvigyan Bhavan, 31, Mahatma Gandhi Marg, Lucknow, Uttar Pradesh, India
- Academy of Scientific and Innovative Research (AcSIR), CSIR-IITR Campus, Lucknow. Uttar Pradesh, India
| | - Snigdha Gupta
- Embryotoxicology Laboratory, Environmental Toxicology Group, CSIR- Indian Institute of Toxicology Research (CSIR-IITR), Vishvigyan Bhavan, 31, Mahatma Gandhi Marg, Lucknow, Uttar Pradesh, India
- Academy of Scientific and Innovative Research (AcSIR), CSIR-IITR Campus, Lucknow. Uttar Pradesh, India
| | - Anshuman Singh
- Embryotoxicology Laboratory, Environmental Toxicology Group, CSIR- Indian Institute of Toxicology Research (CSIR-IITR), Vishvigyan Bhavan, 31, Mahatma Gandhi Marg, Lucknow, Uttar Pradesh, India
| | - Norene A. Buehner
- Dept. of Molecular Biology and Genetics, Cornell University, Ithaca, NY, United States of America
| | - Kristipati Ravi Ram
- Embryotoxicology Laboratory, Environmental Toxicology Group, CSIR- Indian Institute of Toxicology Research (CSIR-IITR), Vishvigyan Bhavan, 31, Mahatma Gandhi Marg, Lucknow, Uttar Pradesh, India
- Academy of Scientific and Innovative Research (AcSIR), CSIR-IITR Campus, Lucknow. Uttar Pradesh, India
- * E-mail:
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Tan NS, Vázquez-Carrera M, Montagner A, Sng MK, Guillou H, Wahli W. Transcriptional control of physiological and pathological processes by the nuclear receptor PPARβ/δ. Prog Lipid Res 2016; 64:98-122. [PMID: 27665713 DOI: 10.1016/j.plipres.2016.09.001] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Revised: 08/31/2016] [Accepted: 09/20/2016] [Indexed: 12/14/2022]
Affiliation(s)
- Nguan Soon Tan
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, 637551, Singapore; Lee Kong Chian School of Medicine, Nanyang Technological University, Academia, 20 College Road, 169856, Singapore; Institute of Molecular and Cell Biology, 61 Biopolis Drive, Proteos, Agency for Science Technology & Research, 138673, Singapore; KK Research Centre, KK Women's and Children's Hospital, 100 Bukit Timah Road, 229899, Singapore.
| | - Manuel Vázquez-Carrera
- Department of Pharmacology and Therapeutic Chemistry, Faculty of Pharmacy, University of Barcelona, Institute of Biomedicine of the University of Barcelona (IBUB), Pediatric Research Institute-Hospital Sant Joan de Déu, Spanish Biomedical Research Centre in Diabetes and Associated Metabolic Diseases (CIBERDEM), Barcelona, Spain
| | | | - Ming Keat Sng
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, 637551, Singapore; Lee Kong Chian School of Medicine, Nanyang Technological University, Academia, 20 College Road, 169856, Singapore
| | - Hervé Guillou
- INRA ToxAlim, UMR1331, Chemin de Tournefeuille, Toulouse Cedex 3, France
| | - Walter Wahli
- Lee Kong Chian School of Medicine, Nanyang Technological University, Academia, 20 College Road, 169856, Singapore; INRA ToxAlim, UMR1331, Chemin de Tournefeuille, Toulouse Cedex 3, France; Center for Integrative Genomics, University of Lausanne, Le Génopode, CH 1015 Lausanne, Switzerland.
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12
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Smirnova OV. Competitive Agonists and Antagonists of Steroid Nuclear Receptors: Evolution of the Concept or Its Reversal. BIOCHEMISTRY (MOSCOW) 2016; 80:1227-34. [PMID: 26567566 DOI: 10.1134/s000629791510003x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The mechanisms displaying pure and mixed steroid agonist/antagonist activity as well as principles underlying in vivo action of selective steroid receptor modulators dependent on tissue or cell type including interaction with various types of nuclear receptors are analyzed in this work. Mechanisms of in vitro action for mixed agonist/antagonist steroids are discussed depending on: specific features of their interaction with receptor hormone-binding pocket; steroid-dependent allosteric modulation of interaction between hormone-receptor complex and hormone response DNA elements; features of interacting hormone-receptor complex with protein transcriptional coregulators; level and tissue-specific composition of transcriptional coregulators. A novel understanding regarding context-selective modulators replacing the concept of steroid agonists and antagonists is discussed.
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Affiliation(s)
- O V Smirnova
- Lomonosov Moscow State University, Biological Faculty, Moscow, 119991, Russia.
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Bhatt JM, Viktorova EG, Busby T, Wyrozumska P, Newman LE, Lin H, Lee E, Wright J, Belov GA, Kahn RA, Sztul E. Oligomerization of the Sec7 domain Arf guanine nucleotide exchange factor GBF1 is dispensable for Golgi localization and function but regulates degradation. Am J Physiol Cell Physiol 2015; 310:C456-69. [PMID: 26718629 DOI: 10.1152/ajpcell.00185.2015] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Accepted: 12/14/2015] [Indexed: 12/15/2022]
Abstract
Members of the large Sec7 domain-containing Arf guanine nucleotide exchange factor (GEF) family have been shown to dimerize through their NH2-terminal dimerization and cyclophilin binding (DCB) and homology upstream of Sec7 (HUS) domains. However, the importance of dimerization in GEF localization and function has not been assessed. We generated a GBF1 mutant (91/130) in which two residues required for oligomerization (K91 and E130 within the DCB domain) were replaced with A and assessed the effects of these mutations on GBF1 localization and cellular functions. We show that 91/130 is compromised in oligomerization but that it targets to the Golgi in a manner indistinguishable from wild-type GBF1 and that it rapidly exchanges between the cytosolic and membrane-bound pools. The 91/130 mutant appears active as it integrates within the functional network at the Golgi, supports Arf activation and COPI recruitment, and sustains Golgi homeostasis and cargo secretion when provided as a sole copy of functional GBF1 in cells. In addition, like wild-type GBF1, the 91/130 mutant supports poliovirus RNA replication, a process requiring GBF1 but believed to be independent of GBF1 catalytic activity. However, oligomerization appears to stabilize GBF1 in cells, and the 91/130 mutant is degraded faster than the wild-type GBF1. Our data support a model in which oligomerization is not a key regulator of GBF1 activity but impacts its function by regulating the cellular levels of GBF1.
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Affiliation(s)
- Jay M Bhatt
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Ekaterina G Viktorova
- Department of Veterinary Medicine, Virginia-Maryland Regional College of Veterinary Medicine, University of Maryland, College Park, Maryland; and
| | - Theodore Busby
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Paulina Wyrozumska
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Laura E Newman
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia
| | - Helen Lin
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Eunjoo Lee
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama
| | - John Wright
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama
| | - George A Belov
- Department of Veterinary Medicine, Virginia-Maryland Regional College of Veterinary Medicine, University of Maryland, College Park, Maryland; and
| | - Richard A Kahn
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia
| | - Elizabeth Sztul
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, Alabama;
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14
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Mazaira GI, Lagadari M, Erlejman AG, Galigniana MD. The Emerging Role of TPR-Domain Immunophilins in the Mechanism of Action of Steroid Receptors. NUCLEAR RECEPTOR RESEARCH 2014. [DOI: 10.11131/2014/101094] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Affiliation(s)
- G. I. Mazaira
- Departamento de Química Biológica-IQUIBICEN, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - M. Lagadari
- Instituto de Biología y Medicina Experimental, CONICET, Buenos Aires, Argentina
| | - A. G. Erlejman
- Departamento de Química Biológica-IQUIBICEN, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - M. D. Galigniana
- Departamento de Química Biológica-IQUIBICEN, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
- Instituto de Biología y Medicina Experimental, CONICET, Buenos Aires, Argentina
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