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Kubickova B, Martinkova S, Bohaciakova D, Nezvedova M, Liu R, Brozman O, Spáčil Z, Hilscherova K. Effects of all-trans and 9-cis retinoic acid on differentiating human neural stem cells in vitro. Toxicology 2023; 487:153461. [PMID: 36805303 PMCID: PMC10019519 DOI: 10.1016/j.tox.2023.153461] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 02/02/2023] [Accepted: 02/14/2023] [Indexed: 02/17/2023]
Abstract
Cyanobacterial blooms are known sources of environmentally-occurring retinoid compounds, including all-trans and 9-cis retinoic acids (RAs). The developmental hazard for aquatic organisms has been described, while the implications for human health hazard assessment are not yet sufficiently characterized. Here, we employ a human neural stem cell model that can differentiate in vitro into a mixed culture of neurons and glia. Cells were exposed to non-cytotoxic 8-1000 nM all-trans or 9-cis RA for 9-18 days (DIV13 and DIV22, respectively). Impact on biomarkers was analyzed on gene expression (RT-qPCR) and protein level (western blot and proteomics) at both time points; network patterning (immunofluorescence) on DIV22. RA exposure significantly concentration-dependently increased gene expression of retinoic acid receptors and the metabolizing enzyme CYP26A1, confirming the chemical-specific response of the model. Expression of thyroid hormone signaling-related genes remained mostly unchanged. Markers of neural progenitors/stem cells (PAX6, SOX1, SOX2, NESTIN) were decreased with increasing RA concentrations, though a basal population remained. Neural markers (DCX, TUJ1, MAP2, NeuN, SYP) remained unchanged or were decreased at high concentrations (200-1000 nM). Conversely, (astro-)glial marker S100β was increased concentration-dependently on DIV22. Together, the biomarker analysis indicates an RA-dependent promotion of glial cell fates over neural differentiation, despite the increased abundance of neural protein biomarkers during differentiation. Interestingly, RA exposure induced substantial changes to the cell culture morphology: while low concentrations resulted in a network-like differentiation pattern, high concentrations (200-1000 nM RA) almost completely prevented such network patterning. After functional confirmation for implications in network function, such morphological features could present a proxy for network formation assessment, an apical key event in (neuro-)developmental Adverse Outcome Pathways. The described application of a human in vitro model for (developmental) neurotoxicity to emerging environmentally-relevant retinoids contributes to the evidence-base for the use of differentiating human in vitro models for human health hazard and risk assessment.
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Affiliation(s)
- Barbara Kubickova
- RECETOX, Faculty of Science, Masaryk University, Kotlarska 2, Brno, Czech Republic.
| | - Sarka Martinkova
- RECETOX, Faculty of Science, Masaryk University, Kotlarska 2, Brno, Czech Republic.
| | - Dasa Bohaciakova
- Masaryk University, Faculty of Medicine, Department of Histology and Embryology, Kamenice 3, 62500 Brno, Czech Republic.
| | - Marketa Nezvedova
- RECETOX, Faculty of Science, Masaryk University, Kotlarska 2, Brno, Czech Republic.
| | - Runze Liu
- RECETOX, Faculty of Science, Masaryk University, Kotlarska 2, Brno, Czech Republic.
| | - Ondrej Brozman
- RECETOX, Faculty of Science, Masaryk University, Kotlarska 2, Brno, Czech Republic.
| | - Zdeněk Spáčil
- RECETOX, Faculty of Science, Masaryk University, Kotlarska 2, Brno, Czech Republic.
| | - Klara Hilscherova
- RECETOX, Faculty of Science, Masaryk University, Kotlarska 2, Brno, Czech Republic.
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2
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Interactions governing transcriptional activity of nuclear receptors. Biochem Soc Trans 2022; 50:1941-1952. [DOI: 10.1042/bst20220338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 11/29/2022] [Accepted: 12/01/2022] [Indexed: 12/23/2022]
Abstract
The key players in transcriptional regulation are transcription factors (TFs), proteins that bind specific DNA sequences. Several mechanisms exist to turn TFs ‘on’ and ‘off’, including ligand binding which induces conformational changes within TFs, subsequently influencing multiple inter- and intramolecular interactions to drive transcriptional responses. Nuclear receptors are a specific family of ligand-regulated TFs whose activity relies on interactions with DNA, coregulator proteins and other receptors. These multidomain proteins also undergo interdomain interactions on multiple levels, further modulating transcriptional outputs. Cooperation between these distinct interactions is critical for appropriate transcription and remains an intense area of investigation. In this review, we report and summarize recent findings that continue to advance our mechanistic understanding of how interactions between nuclear receptors and diverse partners influence transcription.
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Pham B, Cheng Z, Lopez D, Lindsay RJ, Foutch D, Majors RT, Shen T. Statistical Analysis of Protein-Ligand Interaction Patterns in Nuclear Receptor RORγ. Front Mol Biosci 2022; 9:904445. [PMID: 35782874 PMCID: PMC9240913 DOI: 10.3389/fmolb.2022.904445] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Accepted: 05/16/2022] [Indexed: 11/21/2022] Open
Abstract
The receptor RORγ belongs to the nuclear receptor superfamily that senses small signaling molecules and regulates at the gene transcription level. Since RORγ has a high basal activity and plays an important role in immune responses, inhibitors targeting this receptor have been a focus for many studies. The receptor-ligand interaction is complex, and often subtle differences in ligand structure can determine its role as an inverse agonist or an agonist. We examined more than 130 existing RORγ crystal structures that have the same receptor complexed with different ligands. We reported the features of receptor-ligand interaction patterns and the differences between agonist and inverse agonist binding. Specific changes in the contact interaction map are identified to distinguish active and inactive conformations. Further statistical analysis of the contact interaction patterns using principal component analysis reveals a dominant mode which separates allosteric binding vs. canonical binding and a second mode which may indicate active vs. inactive structures. We also studied the nature of constitutive activity by performing a 100-ns computer simulation of apo RORγ. Using constitutively active nuclear receptor CAR as a comparison, we identified a group of conserved contacts that have similar contact strength between the two receptors. These conserved contact interactions, especially a couple key contacts in H11–H12 interaction, can be considered essential to the constitutive activity of RORγ. These protein-ligand and internal protein contact interactions can be useful in the development of new drugs that direct receptor activity.
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Affiliation(s)
- Bill Pham
- Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, TN, United States
| | - Ziju Cheng
- Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, TN, United States
| | - Daniel Lopez
- Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, TN, United States
| | - Richard J. Lindsay
- UT-ORNL Graduate School of Genome Science and Technology, Knoxville, TN, United States
| | - David Foutch
- UT-ORNL Graduate School of Genome Science and Technology, Knoxville, TN, United States
| | - Rily T. Majors
- Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, TN, United States
| | - Tongye Shen
- Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, TN, United States
- *Correspondence: Tongye Shen,
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Watanabe M, Fujihara M, Motoyama T, Kawasaki M, Yamada S, Takamura Y, Ito S, Makishima M, Nakano S, Kakuta H. Discovery of a "Gatekeeper" Antagonist that Blocks Entry Pathway to Retinoid X Receptors (RXRs) without Allosteric Ligand Inhibition in Permissive RXR Heterodimers. J Med Chem 2020; 64:430-439. [PMID: 33356247 DOI: 10.1021/acs.jmedchem.0c01354] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Retinoid X receptor (RXR) heterodimers such as PPAR/RXR, LXR/RXR, and FXR/RXR can be activated by RXR agonists alone and are therefore designated as permissive. Similarly, existing RXR antagonists show allosteric antagonism toward partner receptor agonists in these permissive RXR heterodimers. Here, we show 1-(3-(2-ethoxyethoxy)-5,5,8,8-tetramethyl-5,6,7,8-tetrahydronaphthalen-2-yl)-2-(trifluoromethyl)-1H-benzo[d]imidazole-5-carboxylic acid (14, CBTF-EE) as the first RXR antagonist that does not show allosteric inhibition in permissive RXR heterodimers. This compound was designed based on the hypothesis that RXR antagonists that do not induce conformational changes of RXR would not exhibit such allosteric inhibition. CD spectra and X-ray co-crystallography of the complex of 14 and the RXR ligand binding domain (LBD) confirmed that 14 does not change the conformation of hRXR-LBD. The X-ray structure analysis revealed that 14 binds at the entrance of the ligand binding pocket (LBP), blocking access to the LBP and thus serving as a "gatekeeper".
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Affiliation(s)
- Masaki Watanabe
- Division of Pharmaceutical Sciences, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 1-1-1, Tsushima-naka, Kita-ku, Okayama 700-8530, Japan
| | - Michiko Fujihara
- Division of Pharmaceutical Sciences, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 1-1-1, Tsushima-naka, Kita-ku, Okayama 700-8530, Japan.,AIBIOS Company. Ltd., Tri-Seven Roppongi 8F 7-7-7 Roppongi, Minato-ku, Tokyo 106-0032, Japan
| | - Tomoharu Motoyama
- Graduate School of Integrated Pharmaceutical and Nutritional Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan
| | - Mayu Kawasaki
- Graduate School of Integrated Pharmaceutical and Nutritional Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan
| | - Shoya Yamada
- Division of Pharmaceutical Sciences, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 1-1-1, Tsushima-naka, Kita-ku, Okayama 700-8530, Japan.,Research Fellowship Division, Japan Society for the Promotion of Science, Sumitomo-Ichibancho FS Bldg., 8 Ichibancho, Chiyoda-ku, Tokyo 102-8472, Japan
| | - Yuta Takamura
- Division of Pharmaceutical Sciences, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 1-1-1, Tsushima-naka, Kita-ku, Okayama 700-8530, Japan
| | - Sohei Ito
- Graduate School of Integrated Pharmaceutical and Nutritional Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan
| | - Makoto Makishima
- Division of Biochemistry, Department of Biomedical Sciences, Nihon University School of Medicine, 30-1 Oyaguchi-kamicho, Itabashi-ku, Tokyo 173-8610, Japan
| | - Shogo Nakano
- Graduate School of Integrated Pharmaceutical and Nutritional Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan
| | - Hiroki Kakuta
- Division of Pharmaceutical Sciences, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 1-1-1, Tsushima-naka, Kita-ku, Okayama 700-8530, Japan
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Gupta MN, Alam A, Hasnain SE. Protein promiscuity in drug discovery, drug-repurposing and antibiotic resistance. Biochimie 2020; 175:50-57. [PMID: 32416199 DOI: 10.1016/j.biochi.2020.05.004] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 04/29/2020] [Accepted: 05/04/2020] [Indexed: 12/01/2022]
Abstract
Proteins are supposed to bind to their substrates/ligands in a specific manner via their pre-formed binding sites, according to classical biochemistry. In recent years, several types of deviations from this norm have been observed and called promiscuous behavior. Enzymatic promiscuities allow several biochemical functions to be carried out by the same enzyme. The promiscuous activity can also be the origin of "new proteins" via gene duplication. In more recent years, proteins from prokaryotes, eukaryotes and viruses have been found to have intrinsic disorder and lack a preformed binding site. Intrinsic disorder is exploited in regulatory proteins such as those that are involved in transcription and signal transduction. Such proteins function by folding locally while binding to their ligands or interacting with other proteins. These phenomena have also been classified as examples of protein promiscuity and encompass diverse kinds of ligands that can bind to a protein. Given the significant extent of structural homology in many protein families, it is not surprising that ligands also have been found to display promiscuity. Promiscuous behavior of proteins offers both challenges and opportunities to the drug discovery programs such as drug repurposing. Pathogens when exposed to antibiotics exploit protein promiscuity in several ways to develop resistance to the drug. There is increasing evidence now to support that the disorder in proteins is a major tool used by pathogens for virulence and evade drug action by exploiting protein promiscuity. This review provides a holistic view of this multi-faceted phenomenon called protein promiscuity.
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Affiliation(s)
- Munishwar N Gupta
- Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, New Delhi, 110016, India
| | - Anwar Alam
- ICMR-National Institute of Pathology, Safdarjung Hospital Campus, New Delhi, 110029, India
| | - Seyed E Hasnain
- JH-Institute of Molecular Medicine, Jamia Hamdard, New Delhi, 110062, India; Dr Reddy's Institute of Life Sciences, University of Hyderabad Campus, Professor CR Rao Road, Hyderabad, 500046, India.
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Transcriptome analyses of liver in newly-hatched chicks during the metabolic perturbation of fasting and re-feeding reveals THRSPA as the key lipogenic transcription factor. BMC Genomics 2020; 21:109. [PMID: 32005146 PMCID: PMC6995218 DOI: 10.1186/s12864-020-6525-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Accepted: 01/22/2020] [Indexed: 12/17/2022] Open
Abstract
Background The fasting-refeeding perturbation has been used extensively to reveal specific genes and metabolic pathways that control energy metabolism in the chicken. Most global transcriptional scans of the fasting-refeeding response in liver have focused on juvenile chickens that were 1, 2 or 4 weeks old. The present study was aimed at the immediate post-hatch period, in which newly-hatched chicks were subjected to fasting for 4, 24 or 48 h, then refed for 4, 24 or 48 h, and compared with a fully-fed control group at each age (D1-D4). Results Visual analysis of hepatic gene expression profiles using hierarchical and K-means clustering showed two distinct patterns, genes with higher expression during fasting and depressed expression upon refeeding and those with an opposing pattern of expression, which exhibit very low expression during fasting and more abundant expression with refeeding. Differentially-expressed genes (DEGs), identified from five prominent pair-wise contrasts of fed, fasted and refed conditions, were subjected to Ingenuity Pathway Analysis. This enabled mapping of analysis-ready (AR)-DEGs to canonical and metabolic pathways controlled by distinct gene interaction networks. The largest number of hepatic DEGs was identified by two contrasts: D2FED48h/D2FAST48h (968 genes) and D2FAST48h/D3REFED24h (1198 genes). The major genes acutely depressed by fasting and elevated upon refeeding included ANGTPL, ATPCL, DIO2, FASN, ME1, SCD, PPARG, SREBP2 and THRSPA—a primary lipogenic transcription factor. In contrast, major lipolytic genes were up-regulated by fasting or down-regulated after refeeding, including ALDOB, IL-15, LDHB, LPIN2, NFE2L2, NR3C1, NR0B1, PANK1, PPARA, SERTAD2 and UPP2. Conclusions Transcriptional profiling of liver during fasting/re-feeding of newly-hatched chicks revealed several highly-expressed upstream regulators, which enable the metabolic switch from fasted (lipolytic/gluconeogenic) to fed or refed (lipogenic/thermogenic) states. This rapid homeorhetic shift of whole-body metabolism from a catabolic-fasting state to an anabolic-fed state appears precisely orchestrated by a small number of ligand-activated transcription factors that provide either a fasting-lipolytic state (PPARA, NR3C1, NFE2L2, SERTAD2, FOX01, NR0B1, RXR) or a fully-fed and refed lipogenic/thermogenic state (THRSPA, SREBF2, PPARG, PPARD, JUN, ATF3, CTNNB1). THRSPA has emerged as the key transcriptional regulator that drives lipogenesis and thermogenesis in hatchling chicks, as shown here in fed and re-fed states.
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7
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Pham B, Arons AB, Vincent JG, Fernandez EJ, Shen T. Regulatory Mechanics of Constitutive Androstane Receptors: Basal and Ligand-Directed Actions. J Chem Inf Model 2019; 59:5174-5182. [PMID: 31714771 DOI: 10.1021/acs.jcim.9b00695] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Constitutive androstane receptor (CAR) is a nuclear hormone receptor that primarily functions in sensing and metabolizing xenobiotics. The basal activity of this receptor is relatively high, and CAR is deemed active in the absence of ligand. The (over)activation can promote drug toxicity and tumor growth. Thus, therapeutic treatments seek inverse agonists to inhibit or modulate CAR activities. To advance our understanding of the regulatory mechanisms of CAR, we used computational and experimental approaches to elucidate three aspects of CAR activation and inactivation: (1) ligand-dependent actions, (2) ligand-orthologue specificity, and (3) constitutive activity. For ligand-dependent actions, we examined the ligand-bound simulations and identified two sets of ligand-induced contacts promoting CAR activation via coactivator binding (H11-H12 contact) or inactivation via corepressor binding (H4-H11 contact). For orthologue specificity, we addressed a puzzling fact that murine CAR (mCAR) and human CAR (hCAR) respond differently to the same ligand (CITCO), despite their high sequence homology. We found that the helix H7 of hCAR is responsible for a stronger binding of the ligand CITCO compared to mCAR, hence a stronger CITCO-induced activation. For basal activity, we reported computer-generated unliganded CAR structures and critical mutagenesis (mCAR's V209A and N333D) results of a cell-based transcription assay. Our results reveal that the basal conformation of CAR shares prominent features with the agonist-bound form, and helix HX has an important contribution to the constitutive activity. These findings altogether can be useful for the understanding of constitutively active receptors and the design of drug molecules targeting them.
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Affiliation(s)
- Bill Pham
- Department of Biochemistry & Cellular and Molecular Biology , University of Tennessee , Knoxville , Tennessee 37996 , United States
| | - Avery Bancroft Arons
- Department of Biochemistry & Cellular and Molecular Biology , University of Tennessee , Knoxville , Tennessee 37996 , United States
| | - Jeremy G Vincent
- Department of Biochemistry & Cellular and Molecular Biology , University of Tennessee , Knoxville , Tennessee 37996 , United States
| | - Elias J Fernandez
- Department of Biochemistry & Cellular and Molecular Biology , University of Tennessee , Knoxville , Tennessee 37996 , United States
| | - Tongye Shen
- Department of Biochemistry & Cellular and Molecular Biology , University of Tennessee , Knoxville , Tennessee 37996 , United States
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Lindsay RJ, Pham B, Shen T, McCord RP. Characterizing the 3D structure and dynamics of chromosomes and proteins in a common contact matrix framework. Nucleic Acids Res 2019; 46:8143-8152. [PMID: 29992238 PMCID: PMC6144818 DOI: 10.1093/nar/gky604] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 06/25/2018] [Indexed: 11/13/2022] Open
Abstract
Conformational ensembles of biopolymers, whether proteins or chromosomes, can be described using contact matrices. Principal component analysis (PCA) on the contact data has been used to interrogate both protein and chromosome structures and/or dynamics. However, as these fields have developed separately, variants of PCA have emerged. Previously, a variant we hereby term Implicit-PCA (I-PCA) has been applied to chromosome contact matrices and revealed the spatial segregation of active and inactive chromatin. Separately, Explicit-PCA (E-PCA) has previously been applied to proteins and characterized their correlated structure fluctuations. Here, we swapped analysis methods (I-PCA and E-PCA), applying each to a different biopolymer type (chromosome or protein) than the one for which they were initially developed. We find that applying E-PCA to chromosome distance matrices derived from microscopy data can reveal the dominant motion (concerted fluctuation) of these chromosomes. Further, by applying E-PCA to Hi-C data across the human blood cell lineage, we isolated the aspects of chromosome structure that most strongly differentiate cell types. Conversely, when we applied I-PCA to simulation snapshots of proteins, the major component reported the consensus features of the structure, making this a promising approach for future analysis of semi-structured proteins.
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Affiliation(s)
- Richard J Lindsay
- Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee, Knoxville, TN 37996, USA
| | - Bill Pham
- Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee, Knoxville, TN 37996, USA
| | - Tongye Shen
- Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee, Knoxville, TN 37996, USA
| | - Rachel Patton McCord
- Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee, Knoxville, TN 37996, USA
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9
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Okafor CD, Colucci JK, Ortlund EA. Ligand-Induced Allosteric Effects Governing SR Signaling. NUCLEAR RECEPTOR RESEARCH 2019. [DOI: 10.32527/2019/101382] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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10
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Pham B, Lindsay RJ, Shen T. Effector-Binding-Directed Dimerization and Dynamic Communication between Allosteric Sites of Ribonucleotide Reductase. Biochemistry 2019; 58:697-705. [PMID: 30571104 DOI: 10.1021/acs.biochem.8b01131] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Proteins forming dimers or larger complexes can be strongly influenced by their effector-binding status. We investigated how the effector-binding event is coupled with interface formation via computer simulations, and we quantified the correlation of two types of contact interactions: between the effector and its binding pocket and between protein monomers. This was achieved by connecting the protein dynamics at the monomeric level with the oligomer interface information. We applied this method to ribonucleotide reductase (RNR), an essential enzyme for de novo DNA synthesis. RNR contains two important allosteric sites, the s-site (specificity site) and the a-site (activity site), which bind different effectors. We studied these different binding states with atomistic simulation and used their coarse-grained contact information to analyze the protein dynamics. The results reveal that the effector-protein dynamics at the s-site and dimer interface formation are positively coupled. We further quantify the resonance level between these two events, which can be applied to other similar systems. At the a-site, different effector-binding states (ATP vs dATP) drastically alter the protein dynamics and affect the activity of the enzyme. On the basis of these results, we propose a new mechanism of how the a-site regulates enzyme activation.
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Affiliation(s)
- Bill Pham
- Department of Biochemistry & Cellular and Molecular Biology , University of Tennessee , Knoxville , Tennessee 37996 , United States
| | - Richard J Lindsay
- UT-ORNL Graduate School of Genome Science and Technology , Knoxville , Tennessee 37996 , United States
| | - Tongye Shen
- Department of Biochemistry & Cellular and Molecular Biology , University of Tennessee , Knoxville , Tennessee 37996 , United States
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11
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Hyde CJ, Elizur A, Ventura T. The crustacean ecdysone cassette: A gatekeeper for molt and metamorphosis. J Steroid Biochem Mol Biol 2019; 185:172-183. [PMID: 30157455 DOI: 10.1016/j.jsbmb.2018.08.012] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Revised: 08/21/2018] [Accepted: 08/25/2018] [Indexed: 10/28/2022]
Abstract
Arthropods have long been utilized as models to explore molecular function, and the findings derived from them can be applied throughout metazoa, including as a basis for medical research. This has led to the adoption of many representative insect models beyond Drosophila, as each lends its own unique perspective to questions in endocrinology and genetics. However, non-insect arthropods are yet to be realised for the potential insight they may provide in such studies. The Crustacea are among the most ancient arthropods from which insects descended, comprising a huge variety of life histories and ecological roles. Of the events in a typical crustacean development, metamorphosis is perhaps the most ubiquitous, challenging and highly studied. Despite this, our knowledge of the endocrinology which underpins metamorphosis is rudimentary at best; although several key molecules have been identified and studied in depth, the link between them is quite nebulous and leans heavily on well-explored insect models, which diverged from the Pancrustacea over 450 million years ago. As omics technologies become increasingly accessible, they bring the prospect of explorative molecular research which will allow us to uncover components and pathways unique to crustaceans. This review reconciles known components of crustacean metamorphosis and reflects on our findings in insects to outline a future search space, with focus given to the ecdysone cascade. To expand our knowledge of this ubiquitous endocrine system not only aids in our understanding of crustacean metamorphosis, but also provides a deeper insight into the adaptive capacity of arthropods throughout evolution.
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Affiliation(s)
- Cameron J Hyde
- Genecology Research Centre, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, 4 Locked Bag, Maroochydore, Queensland, 4558, Australia
| | - Abigail Elizur
- Genecology Research Centre, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, 4 Locked Bag, Maroochydore, Queensland, 4558, Australia
| | - Tomer Ventura
- Genecology Research Centre, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, 4 Locked Bag, Maroochydore, Queensland, 4558, Australia.
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Lindsay RJ, Siess J, Lohry DP, McGee TS, Ritchie JS, Johnson QR, Shen T. Characterizing protein conformations by correlation analysis of coarse-grained contact matrices. J Chem Phys 2018; 148:025101. [PMID: 29331124 DOI: 10.1063/1.5004141] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We have developed a method to capture the essential conformational dynamics of folded biopolymers using statistical analysis of coarse-grained segment-segment contacts. Previously, the residue-residue contact analysis of simulation trajectories was successfully applied to the detection of conformational switching motions in biomolecular complexes. However, the application to large protein systems (larger than 1000 amino acid residues) is challenging using the description of residue contacts. Also, the residue-based method cannot be used to compare proteins with different sequences. To expand the scope of the method, we have tested several coarse-graining schemes that group a collection of consecutive residues into a segment. The definition of these segments may be derived from structural and sequence information, while the interaction strength of the coarse-grained segment-segment contacts is a function of the residue-residue contacts. We then perform covariance calculations on these coarse-grained contact matrices. We monitored how well the principal components of the contact matrices is preserved using various rendering functions. The new method was demonstrated to assist the reduction of the degrees of freedom for describing the conformation space, and it potentially allows for the analysis of a system that is approximately tenfold larger compared with the corresponding residue contact-based method. This method can also render a family of similar proteins into the same conformational space, and thus can be used to compare the structures of proteins with different sequences.
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Affiliation(s)
- Richard J Lindsay
- UT-ORNL Graduate School of Genome Science and Technology, Knoxville, Tennessee 37996, USA
| | - Jan Siess
- Department of Mathematics, Rutgers University, Piscataway, New Jersey 08854, USA
| | - David P Lohry
- Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - Trevor S McGee
- Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - Jordan S Ritchie
- Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - Quentin R Johnson
- UT-ORNL Center for Molecular Biophysics, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, USA
| | - Tongye Shen
- UT-ORNL Center for Molecular Biophysics, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, USA
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Abstract
The nuclear receptor family of transcription factor proteins mediates endocrine function and plays critical roles in the development, physiology and pharmacology. Malfunctioning nuclear receptors are associated with several disease states. The functional activity of nuclear receptors is regulated by small molecular hormonal and synthetic molecules. Multiple sources of evidence have identified and distinguished between the different allosteric pathways initiated by ligands, DNA and cofactors such as co-activators and co-repressors. Also, these biophysical studies are attempting to determine how these pathways that regulate co-activator and DNA recognition can control gene transcription. Thus, there is a growing interest in determining the genome-scale impact of allostery in nuclear receptors. Today, it is accepted that a detailed understanding of the allosteric regulatory pathways within the nuclear receptor molecular complex will enable the development of efficient drug therapies in the long term.
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Affiliation(s)
- Elias J Fernandez
- Department of Biochemistry & Cellular and Molecular Biology, The University of Tennessee, USA.
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Johnson QR, Lindsay RJ, Shen T. CAMERRA: An analysis tool for the computation of conformational dynamics by evaluating residue-residue associations. J Comput Chem 2018; 39:1568-1578. [PMID: 29464733 DOI: 10.1002/jcc.25192] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Revised: 01/04/2018] [Accepted: 01/29/2018] [Indexed: 12/20/2022]
Abstract
A computational method which extracts the dominant motions from an ensemble of biomolecular conformations via a correlation analysis of residue-residue contacts is presented. The algorithm first renders the structural information into contact matrices, then constructs the collective modes based on the correlated dynamics of a selected set of dynamic contacts. Associated programs can bridge the results for further visualization using graphics software. The aim of this method is to provide an analysis of conformations of biopolymers from the contact viewpoint. It may assist a systematical uncovering of conformational switching mechanisms existing in proteins and biopolymer systems in general by statistical analysis of simulation snapshots. In contrast to conventional correlation analyses of Cartesian coordinates (such as distance covariance analysis and Cartesian principal component analysis), this program also provides an alternative way to locate essential collective motions in general. Herein, we detail the algorithm in a stepwise manner and comment on the importance of the method as applied to decoding allosteric mechanisms. © 2018 Wiley Periodicals, Inc.
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Affiliation(s)
- Quentin R Johnson
- National Institute for Mathematical and Biological Synthesis, Knoxville, Tennessee, 37996.,Oak Ridge National Laboratory, UT-ORNL Center for Molecular Biophysics, Oak Ridge, Tennessee, 37830
| | - Richard J Lindsay
- Oak Ridge National Laboratory, UT-ORNL Center for Molecular Biophysics, Oak Ridge, Tennessee, 37830.,UT-ORNL Graduate School of Genome Science and Technology, Knoxville, Tennessee, 37996
| | - Tongye Shen
- Oak Ridge National Laboratory, UT-ORNL Center for Molecular Biophysics, Oak Ridge, Tennessee, 37830.,Department of Biochemistry Cellular and Molecular Biology, University of Tennessee, Knoxville, Tennessee, 37996
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