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Piserchio A, Dalby KN, Ghose R. Revealing eEF-2 kinase: recent structural insights into function. Trends Biochem Sci 2024; 49:169-182. [PMID: 38103971 PMCID: PMC10950556 DOI: 10.1016/j.tibs.2023.11.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Revised: 11/14/2023] [Accepted: 11/17/2023] [Indexed: 12/19/2023]
Abstract
The α-kinase eukaryotic elongation factor 2 kinase (eEF-2K) regulates translational elongation by phosphorylating its ribosome-associated substrate, the GTPase eEF-2. eEF-2K is activated by calmodulin (CaM) through a distinctive mechanism unlike that in other CaM-dependent kinases (CAMK). We describe recent structural insights into this unique activation process and examine the effects of specific regulatory signals on this mechanism. We also highlight key unanswered questions to guide future structure-function studies. These include structural mechanisms which enable eEF-2K to interact with upstream/downstream partners and facilitate its integration of diverse inputs, including Ca2+ transients, phosphorylation mediated by energy/nutrient-sensing pathways, pH changes, and metabolites. Answering these questions is key to establishing how eEF-2K harmonizes translation with cellular requirements within the boundaries of its molecular landscape.
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Affiliation(s)
- Andrea Piserchio
- Department of Chemistry and Biochemistry, The City College of New York, New York, NY 10031, USA
| | - Kevin N Dalby
- Division of Chemical Biology and Medicinal Chemistry, The University of Texas, Austin, TX 78712, USA.
| | - Ranajeet Ghose
- Department of Chemistry and Biochemistry, The City College of New York, New York, NY 10031, USA; The Graduate Center of The City University of New York (CUNY), New York, NY 10016, USA.
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2
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Wu C, Balakrishnan R, Braniff N, Mori M, Manzanarez G, Zhang Z, Hwa T. Cellular perception of growth rate and the mechanistic origin of bacterial growth law. Proc Natl Acad Sci U S A 2022; 119:e2201585119. [PMID: 35544692 DOI: 10.1073/pnas.2201585119] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Many cellular activities in bacteria are organized according to their growth rate. The notion that ppGpp measures the cell’s growth rate is well accepted in the field of bacterial physiology. However, despite decades of interrogation and the identification of multiple molecular interactions that connects ppGpp to some aspects of cell growth, we lack a system-level, quantitative picture of how this alleged “measurement” is performed. Through quantitative experiments, we show that the ppGpp pool responds inversely to the rate of translational elongation in Escherichia coli. Together with its roles in inhibiting ribosome biogenesis and activity, ppGpp closes a key regulatory circuit that enables the cell to perceive and control the rate of its growth across conditions. The celebrated linear growth law relating the ribosome content and growth rate emerges as a consequence of keeping a supply of ribosome reserves while maintaining elongation rate in slow growth conditions. Further analysis suggests the elongation rate itself is detected by sensing the ratio of dwelling and translocating ribosomes, a strategy employed to collapse the complex, high-dimensional dynamics of the molecular processes underlying cell growth to perceive the physiological state of the whole.
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3
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Piserchio A, Long K, Lee K, Kumar EA, Abzalimov R, Dalby KN, Ghose R. Structural dynamics of the complex of calmodulin with a minimal functional construct of eukaryotic elongation factor 2 kinase and the role of Thr348 autophosphorylation. Protein Sci 2021; 30:1221-1234. [PMID: 33890716 DOI: 10.1002/pro.4087] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2020] [Revised: 04/15/2021] [Indexed: 12/31/2022]
Abstract
The calmodulin (CaM) activated α-kinase, eukaryotic elongation factor 2 kinase (eEF-2K), plays a central role in regulating translational elongation by phosphorylating eukaryotic elongation factor 2 (eEF-2), thereby reducing its ability to associate with the ribosome and suppressing global protein synthesis. Using TR (for truncated), a minimal functional construct of eEF-2K, and utilizing hydrogen/deuterium exchange mass spectrometry (HXMS), solution-state nuclear magnetic resonance (NMR) and biochemical approaches, we investigate the conformational changes accompanying complex formation between Ca2+ -CaM and TR and the effects of autophosphorylation of the latter at Thr348, its primary regulatory site. Our results suggest that a CaM C-lobe surface, complementary to the one involved in recognizing the calmodulin-binding domain (CBD) of TR, provides a secondary TR-interaction platform. CaM helix F, which is part of this secondary surface, responds to both Thr348 phosphorylation and pH changes, indicating its integration into an allosteric network that encompasses both components of the Ca2+ -CaM•TR complex. Solution NMR data suggest that CaMH107K , which carries a helix F mutation, is compromised in its ability to drive the conformational changes in TR necessary to enable efficient Thr348 phosphorylation. Biochemical studies confirm the diminished capacity of CaMH107K to induce TR autophosphorylation compared to wild-type CaM.
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Affiliation(s)
- Andrea Piserchio
- Department of Chemistry and Biochemistry, The City College of New York, New York, New York, USA
| | - Kimberly Long
- Division of Chemical Biology and Medicinal Chemistry, University of Texas, Austin, Texas, USA
| | - Kwangwoon Lee
- Department of Chemistry and Biochemistry, The City College of New York, New York, New York, USA.,Graduate Programs in Biochemistry, The Graduate Center of CUNY, New York, New York, USA.,Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA.,Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts, USA
| | - Eric A Kumar
- Division of Chemical Biology and Medicinal Chemistry, University of Texas, Austin, Texas, USA
| | - Rinat Abzalimov
- Biomolecular Mass Spectrometry Facility, CUNY ASRC, New York, New York, USA
| | - Kevin N Dalby
- Division of Chemical Biology and Medicinal Chemistry, University of Texas, Austin, Texas, USA.,Graduate Program in Cell and Molecular Biology, University of Texas, Austin, Texas, USA
| | - Ranajeet Ghose
- Department of Chemistry and Biochemistry, The City College of New York, New York, New York, USA.,Graduate Programs in Biochemistry, The Graduate Center of CUNY, New York, New York, USA.,Graduate Programs in Chemistry, The Graduate Center of CUNY, New York, New York, USA.,Graduate Programs in Physics, The Graduate Center of CUNY, New York, New York, USA
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Shen Y, Zhang ZC, Cheng S, Liu A, Zuo J, Xia S, Liu X, Liu W, Jia Z, Xie W, Han J. PQBP1 promotes translational elongation and regulates hippocampal mGluR-LTD by suppressing eEF2 phosphorylation. Mol Cell 2021; 81:1425-1438.e10. [PMID: 33662272 DOI: 10.1016/j.molcel.2021.01.032] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 12/07/2020] [Accepted: 01/21/2021] [Indexed: 10/22/2022]
Abstract
Eukaryotic elongation factor 2 (eEF2) mediates translocation of peptidyl-tRNA from the ribosomal A site to the P site to promote translational elongation. Its phosphorylation on Thr56 by its single known kinase eEF2K inactivates it and inhibits translational elongation. Extensive studies have revealed that different signal cascades modulate eEF2K activity, but whether additional factors regulate phosphorylation of eEF2 remains unclear. Here, we find that the X chromosome-linked intellectual disability protein polyglutamine-binding protein 1 (PQBP1) specifically binds to non-phosphorylated eEF2 and suppresses eEF2K-mediated phosphorylation at Thr56. Loss of PQBP1 significantly reduces general protein synthesis by suppressing translational elongation. Moreover, we show that PQBP1 regulates hippocampal metabotropic glutamate receptor-dependent long-term depression (mGluR-LTD) and mGluR-LTD-associated behaviors by suppressing eEF2K-mediated phosphorylation. Our results identify PQBP1 as a novel regulator in translational elongation and mGluR-LTD, and this newly revealed regulator in the eEF2K/eEF2 pathway is also an excellent therapeutic target for various disease conditions, such as neural diseases, virus infection, and cancer.
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Affiliation(s)
- Yuqian Shen
- School of Life Science and Technology, Key Laboratory of Developmental Genes and Human Disease, Southeast University, Nanjing 210096, China
| | - Zi Chao Zhang
- School of Life Science and Technology, Key Laboratory of Developmental Genes and Human Disease, Southeast University, Nanjing 210096, China; Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu 226001, China.
| | - Shanshan Cheng
- School of Life Science and Technology, Key Laboratory of Developmental Genes and Human Disease, Southeast University, Nanjing 210096, China
| | - An Liu
- School of Life Science and Technology, Key Laboratory of Developmental Genes and Human Disease, Southeast University, Nanjing 210096, China
| | - Jian Zuo
- School of Life Science and Technology, Key Laboratory of Developmental Genes and Human Disease, Southeast University, Nanjing 210096, China
| | - Shuting Xia
- Institute of Neuroscience, Soochow University, Suzhou 215000, China
| | - Xian Liu
- School of Life Science and Technology, Key Laboratory of Developmental Genes and Human Disease, Southeast University, Nanjing 210096, China
| | - Wenhua Liu
- School of Life Science and Technology, Key Laboratory of Developmental Genes and Human Disease, Southeast University, Nanjing 210096, China
| | - Zhengping Jia
- Neurosciences and Mental Health Program, Hospital for Sick Children, University of Toronto, Toronto, ON M5S 1A1, Canada
| | - Wei Xie
- School of Life Science and Technology, Key Laboratory of Developmental Genes and Human Disease, Southeast University, Nanjing 210096, China; Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu 226001, China
| | - Junhai Han
- School of Life Science and Technology, Key Laboratory of Developmental Genes and Human Disease, Southeast University, Nanjing 210096, China; Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu 226001, China; Department of Neurology, Affiliated ZhongDa Hospital, Institute of Neuropsychiatry, Southeast University, Nanjing, Jiangsu 210009, China.
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5
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Grund A, Szaroszyk M, Korf-Klingebiel M, Malek Mohammadi M, Trogisch FA, Schrameck U, Gigina A, Tiedje C, Gaestel M, Kraft T, Hegermann J, Batkai S, Thum T, Perrot A, Remedios CD, Riechert E, Völkers M, Doroudgar S, Jungmann A, Bauer R, Yin X, Mayr M, Wollert KC, Pich A, Xiao H, Katus HA, Bauersachs J, Müller OJ, Heineke J. TIP30 counteracts cardiac hypertrophy and failure by inhibiting translational elongation. EMBO Mol Med 2019; 11:e10018. [PMID: 31468715 PMCID: PMC6783653 DOI: 10.15252/emmm.201810018] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Revised: 08/01/2019] [Accepted: 08/06/2019] [Indexed: 12/17/2022] Open
Abstract
Pathological cardiac overload induces myocardial protein synthesis and hypertrophy, which predisposes to heart failure. To inhibit hypertrophy therapeutically, the identification of negative regulators of cardiomyocyte protein synthesis is needed. Here, we identified the tumor suppressor protein TIP30 as novel inhibitor of cardiac hypertrophy and dysfunction. Reduced TIP30 levels in mice entailed exaggerated cardiac growth during experimental pressure overload, which was associated with cardiomyocyte cellular hypertrophy, increased myocardial protein synthesis, reduced capillary density, and left ventricular dysfunction. Pharmacological inhibition of protein synthesis improved these defects. Our results are relevant for human disease, since we found diminished cardiac TIP30 levels in samples from patients suffering from end‐stage heart failure or hypertrophic cardiomyopathy. Importantly, therapeutic overexpression of TIP30 in mouse hearts inhibited cardiac hypertrophy and improved left ventricular function during pressure overload and in cardiomyopathic mdx mice. Mechanistically, we identified a previously unknown anti‐hypertrophic mechanism, whereby TIP30 binds the eukaryotic elongation factor 1A (eEF1A) to prevent the interaction with its essential co‐factor eEF1B2 and translational elongation. Therefore, TIP30 could be a therapeutic target to counteract cardiac hypertrophy.
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Affiliation(s)
- Andrea Grund
- Department for Cardiology and Angiology, Hannover Medical School, Hannover, Germany.,Department of Cardiovascular Research, European Center for Angioscience (ECAS), Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Malgorzata Szaroszyk
- Department for Cardiology and Angiology, Hannover Medical School, Hannover, Germany
| | | | - Mona Malek Mohammadi
- Department for Cardiology and Angiology, Hannover Medical School, Hannover, Germany.,Department of Cardiovascular Research, European Center for Angioscience (ECAS), Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Felix A Trogisch
- Department of Cardiovascular Research, European Center for Angioscience (ECAS), Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Ulrike Schrameck
- Department for Cardiology and Angiology, Hannover Medical School, Hannover, Germany
| | - Anna Gigina
- Department for Cardiology and Angiology, Hannover Medical School, Hannover, Germany
| | - Christopher Tiedje
- Institute of Cell Biochemistry, Hannover Medical School, Hannover, Germany
| | - Matthias Gaestel
- Institute of Cell Biochemistry, Hannover Medical School, Hannover, Germany
| | - Theresia Kraft
- Institute for Molecular and Cellphysiology, Hannover Medical School, Hannover, Germany
| | - Jan Hegermann
- Research Core Unit Electron Microscopy, Hannover Medical School, Hannover, Germany
| | - Sandor Batkai
- Institute of Molecular and Translational Therapeutic Strategies (IMTTS), Hannover Medical School, Hannover, Germany
| | - Thomas Thum
- Institute of Molecular and Translational Therapeutic Strategies (IMTTS), Hannover Medical School, Hannover, Germany.,Cluster of Excellence Rebirth, Hannover Medical School, Hannover, Germany
| | - Andreas Perrot
- Experimental and Clinical Research Center, A Joint Cooperation of Max-Delbrück Center for Molecular Medicine and Charité-Universitätsmedizin Berlin, Berlin, Germany
| | | | - Eva Riechert
- Department of Cardiology, Angiology and Pneumology, Medical Faculty of Heidelberg, University of Heidelberg, Heidelberg, Germany
| | - Mirko Völkers
- Department of Cardiology, Angiology and Pneumology, Medical Faculty of Heidelberg, University of Heidelberg, Heidelberg, Germany.,DZHK (German Centre for Cardiovascular Research), Partner Site Heidelberg/Mannheim, Heidelberg, Germany
| | - Shirin Doroudgar
- Department of Cardiology, Angiology and Pneumology, Medical Faculty of Heidelberg, University of Heidelberg, Heidelberg, Germany.,DZHK (German Centre for Cardiovascular Research), Partner Site Heidelberg/Mannheim, Heidelberg, Germany
| | - Andreas Jungmann
- Department of Cardiology, Angiology and Pneumology, Medical Faculty of Heidelberg, University of Heidelberg, Heidelberg, Germany
| | - Ralf Bauer
- Department of Cardiology, Angiology and Pneumology, Medical Faculty of Heidelberg, University of Heidelberg, Heidelberg, Germany
| | - Xiaoke Yin
- King's British Heart Foundation Centre, King's College London, London, UK
| | - Manuel Mayr
- King's British Heart Foundation Centre, King's College London, London, UK
| | - Kai C Wollert
- Department for Cardiology and Angiology, Hannover Medical School, Hannover, Germany.,Cluster of Excellence Rebirth, Hannover Medical School, Hannover, Germany
| | - Andreas Pich
- Core Unit Proteomics, Hannover Medical School, Hannover, Germany
| | - Hua Xiao
- Department of Physiology, Michigan State University, East Lansing, MI, USA
| | - Hugo A Katus
- Department of Cardiology, Angiology and Pneumology, Medical Faculty of Heidelberg, University of Heidelberg, Heidelberg, Germany.,DZHK (German Centre for Cardiovascular Research), Partner Site Heidelberg/Mannheim, Heidelberg, Germany
| | - Johann Bauersachs
- Department for Cardiology and Angiology, Hannover Medical School, Hannover, Germany.,Cluster of Excellence Rebirth, Hannover Medical School, Hannover, Germany
| | - Oliver J Müller
- Department of Cardiology, Angiology and Pneumology, Medical Faculty of Heidelberg, University of Heidelberg, Heidelberg, Germany.,DZHK (German Centre for Cardiovascular Research), Partner Site Heidelberg/Mannheim, Heidelberg, Germany.,Department of Internal Medicine III, Cardiology, Angiology and Intensive Care Medicine, Universitätsklinikum Schleswig-Holstein, Kiel, Germany
| | - Joerg Heineke
- Department for Cardiology and Angiology, Hannover Medical School, Hannover, Germany.,Department of Cardiovascular Research, European Center for Angioscience (ECAS), Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany.,Cluster of Excellence Rebirth, Hannover Medical School, Hannover, Germany.,DZHK (German Centre for Cardiovascular Research), Partner Site Heidelberg/Mannheim, Heidelberg, Germany
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6
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Piserchio A, Will N, Giles DH, Hajredini F, Dalby KN, Ghose R. Solution Structure of the Carboxy-Terminal Tandem Repeat Domain of Eukaryotic Elongation Factor 2 Kinase and Its Role in Substrate Recognition. J Mol Biol 2019; 431:2700-2717. [PMID: 31108082 PMCID: PMC6599559 DOI: 10.1016/j.jmb.2019.05.019] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 04/15/2019] [Accepted: 05/12/2019] [Indexed: 12/31/2022]
Abstract
Eukaryotic elongation factor 2 kinase (eEF-2K), an atypical calmodulin-activated protein kinase, regulates translational elongation by phosphorylating its substrate, eukaryotic elongation factor 2 (eEF-2), thereby reducing its affinity for the ribosome. The activation and activity of eEF-2K are critical for survival under energy-deprived conditions and is implicated in a variety of essential physiological processes. Previous biochemical experiments have indicated that the binding site for the substrate eEF-2 is located in the C-terminal domain of eEF-2K, a region predicted to harbor several α-helical repeats. Here, using NMR methodology, we have determined the solution structure of a C-terminal fragment of eEF-2K, eEF-2K562-725 that encodes two α-helical repeats. The structure of eEF-2K562-725 shows signatures characteristic of TPR domains and of their SEL1-like sub-family. Furthermore, using the analyses of NMR spectral perturbations and ITC measurements, we have localized the eEF-2 binding site on eEF-2K562-725. We find that eEF-2K562-725 engages eEF-2 with an affinity comparable to that of the full-length enzyme. Furthermore, eEF-2K562-725 is able to inhibit the phosphorylation of eEF-2 by full-length eEF-2K in trans. Our present studies establish that eEF-2K562-725 encodes the major elements necessary to enable the eEF-2K/eEF-2 interactions.
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Affiliation(s)
- Andrea Piserchio
- Department of Chemistry and Biochemistry, The City College of New York, NewYork, NY 10031, USA
| | - Nathan Will
- Department of Chemistry and Biochemistry, The City College of New York, NewYork, NY 10031, USA; Graduate Program in Biochemistry, The Graduate Center of CUNY, New York, NY 10016, USA
| | - David H Giles
- Graduate Program in Cell and Molecular Biology, University of Texas, Austin, TX 78712, USA
| | - Fatlum Hajredini
- Department of Chemistry and Biochemistry, The City College of New York, NewYork, NY 10031, USA; Graduate Program in Biochemistry, The Graduate Center of CUNY, New York, NY 10016, USA
| | - Kevin N Dalby
- Graduate Program in Cell and Molecular Biology, University of Texas, Austin, TX 78712, USA; Division of Chemical Biology and Medicinal Chemistry, University of Texas, Austin, TX 78712, USA
| | - Ranajeet Ghose
- Department of Chemistry and Biochemistry, The City College of New York, NewYork, NY 10031, USA; Graduate Program in Biochemistry, The Graduate Center of CUNY, New York, NY 10016, USA; Graduate Program in Chemistry, The Graduate Center of CUNY, New York, NY 10016, USA; Graduate Program in Physics, The Graduate Center of CUNY, New York, NY 10016, USA.
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Hurley JM, Jankowski MS, De Los Santos H, Crowell AM, Fordyce SB, Zucker JD, Kumar N, Purvine SO, Robinson EW, Shukla A, Zink E, Cannon WR, Baker SE, Loros JJ, Dunlap JC. Circadian Proteomic Analysis Uncovers Mechanisms of Post-Transcriptional Regulation in Metabolic Pathways. Cell Syst 2018; 7:613-626.e5. [PMID: 30553726 DOI: 10.1016/j.cels.2018.10.014] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Revised: 08/12/2018] [Accepted: 10/29/2018] [Indexed: 12/20/2022]
Abstract
Transcriptional and translational feedback loops in fungi and animals drive circadian rhythms in transcript levels that provide output from the clock, but post-transcriptional mechanisms also contribute. To determine the extent and underlying source of this regulation, we applied newly developed analytical tools to a long-duration, deeply sampled, circadian proteomics time course comprising half of the proteome. We found a quarter of expressed proteins are clock regulated, but >40% of these do not arise from clock-regulated transcripts, and our analysis predicts that these protein rhythms arise from oscillations in translational rates. Our data highlighted the impact of the clock on metabolic regulation, with central carbon metabolism reflecting both transcriptional and post-transcriptional control and opposing metabolic pathways showing peak activities at different times of day. The transcription factor CSP-1 plays a role in this metabolic regulation, contributing to the rhythmicity and phase of clock-regulated proteins.
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Brooks SS, Wall AL, Golzio C, Reid DW, Kondyles A, Willer JR, Botti C, Nicchitta CV, Katsanis N, Davis EE. A novel ribosomopathy caused by dysfunction of RPL10 disrupts neurodevelopment and causes X-linked microcephaly in humans. Genetics 2014; 198:723-33. [PMID: 25316788 DOI: 10.1534/genetics.114.168211] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Neurodevelopmental defects in humans represent a clinically heterogeneous group of disorders. Here, we report the genetic and functional dissection of a multigenerational pedigree with an X-linked syndromic disorder hallmarked by microcephaly, growth retardation, and seizures. Using an X-linked intellectual disability (XLID) next-generation sequencing diagnostic panel, we identified a novel missense mutation in the gene encoding 60S ribosomal protein L10 (RPL10), a locus associated previously with autism spectrum disorders (ASD); the p.K78E change segregated with disease under an X-linked recessive paradigm while, consistent with causality, carrier females exhibited skewed X inactivation. To examine the functional consequences of the p.K78E change, we modeled RPL10 dysfunction in zebrafish. We show that endogenous rpl10 expression is augmented in anterior structures, and that suppression decreases head size in developing morphant embryos, concomitant with reduced bulk translation and increased apoptosis in the brain. Subsequently, using in vivo complementation, we demonstrate that p.K78E is a loss-of-function variant. Together, our findings suggest that a mutation within the conserved N-terminal end of RPL10, a protein in close proximity to the peptidyl transferase active site of the 60S ribosomal subunit, causes severe defects in brain formation and function.
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