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Scaltsoyiannes V, Corre N, Waltz F, Giegé P. Types and Functions of Mitoribosome-Specific Ribosomal Proteins across Eukaryotes. Int J Mol Sci 2022; 23:ijms23073474. [PMID: 35408834 PMCID: PMC8998825 DOI: 10.3390/ijms23073474] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 03/17/2022] [Accepted: 03/21/2022] [Indexed: 02/04/2023] Open
Abstract
Mitochondria are key organelles that combine features inherited from their bacterial endosymbiotic ancestor with traits that arose during eukaryote evolution. These energy producing organelles have retained a genome and fully functional gene expression machineries including specific ribosomes. Recent advances in cryo-electron microscopy have enabled the characterization of a fast-growing number of the low abundant membrane-bound mitochondrial ribosomes. Surprisingly, mitoribosomes were found to be extremely diverse both in terms of structure and composition. Still, all of them drastically increased their number of ribosomal proteins. Interestingly, among the more than 130 novel ribosomal proteins identified to date in mitochondria, most of them are composed of a-helices. Many of them belong to the nuclear encoded super family of helical repeat proteins. Here we review the diversity of functions and the mode of action held by the novel mitoribosome proteins and discuss why these proteins that share similar helical folds were independently recruited by mitoribosomes during evolution in independent eukaryote clades.
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Affiliation(s)
- Vassilis Scaltsoyiannes
- CNRS, Institut de Biologie Moléculaire des Plantes, Université de Strasbourg, 67084 Strasbourg, France; (V.S.); (N.C.)
| | - Nicolas Corre
- CNRS, Institut de Biologie Moléculaire des Plantes, Université de Strasbourg, 67084 Strasbourg, France; (V.S.); (N.C.)
| | - Florent Waltz
- CNRS, Institut de Biologie Moléculaire des Plantes, Université de Strasbourg, 67084 Strasbourg, France; (V.S.); (N.C.)
- Helmholtz Pioneer Campus, Helmholtz Zentrum München, Ingolstädter Landstraße 1, 85764 Munich, Germany
- Correspondence: (F.W.); (P.G.); Tel.: +33-3-6715-5363 (P.G.); Fax: +33-3-8861-4442 (P.G.)
| | - Philippe Giegé
- CNRS, Institut de Biologie Moléculaire des Plantes, Université de Strasbourg, 67084 Strasbourg, France; (V.S.); (N.C.)
- Correspondence: (F.W.); (P.G.); Tel.: +33-3-6715-5363 (P.G.); Fax: +33-3-8861-4442 (P.G.)
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2
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Salaikumaran MR, Badiger VP, Burra VLSP. 16S rRNA Methyltransferases as Novel Drug Targets Against Tuberculosis. Protein J 2022; 41:97-130. [PMID: 35112243 DOI: 10.1007/s10930-021-10029-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/28/2021] [Indexed: 11/28/2022]
Abstract
Tuberculosis (TB) is an airborne infectious disease caused by Mycobacterium tuberculosis (M.tb) whose natural history traces back to 70,000 years. TB remains a major global health burden. Methylation is a type of post-replication, post-transcriptional and post-translational epi-genetic modification involved in transcription, translation, replication, tissue specific expression, embryonic development, genomic imprinting, genome stability and chromatin structure, protein protein interactions and signal transduction indicating its indispensable role in survival of a pathogen like M.tb. The pathogens use this epigenetic mechanism to develop resistance against certain drug molecules and survive the lethality. Drug resistance has become a major challenge to tackle and also a major concern raised by WHO. Methyltransferases are enzymes that catalyze the methylation of various substrates. None of the current TB targets belong to methyltransferases which provides therapeutic opportunities to develop novel drugs through studying methyltransferases as potential novel targets against TB. Targeting 16S rRNA methyltransferases serves two purposes simultaneously: a) translation inhibition and b) simultaneous elimination of the ability to methylate its substrates hence stopping the emergence of drug resistance strains. There are ~ 40 different rRNA methyltransferases and 13 different 16S rRNA specific methyltransferases which are unexplored and provide a huge opportunity for treatment of TB.
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Affiliation(s)
- M R Salaikumaran
- Centre for Advanced Research and Innovation in Structural Biology of Diseases, K L E F (Deemed To Be) University, Vaddeswaram, Andhra Pradesh, 522 502, India
| | - Veena P Badiger
- Centre for Advanced Research and Innovation in Structural Biology of Diseases, K L E F (Deemed To Be) University, Vaddeswaram, Andhra Pradesh, 522 502, India
| | - V L S Prasad Burra
- Centre for Advanced Research and Innovation in Structural Biology of Diseases, K L E F (Deemed To Be) University, Vaddeswaram, Andhra Pradesh, 522 502, India.
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3
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Jiang H, Qin X, Wang Q, Xu Q, Wang J, Wu Y, Chen W, Wang C, Zhang T, Xing D, Zhang R. Application of carbohydrates in approved small molecule drugs: A review. Eur J Med Chem 2021; 223:113633. [PMID: 34171659 DOI: 10.1016/j.ejmech.2021.113633] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 06/04/2021] [Accepted: 06/06/2021] [Indexed: 12/24/2022]
Abstract
Carbohydrates are an important energy source and play numerous key roles in all living organisms. Carbohydrates chemistry involved in diagnosis and treatment of diseases has been attracting increasing attention. Carbohydrates could be one of the major focuses of new drug discovery. Currently, however, carbohydrate-containing drugs account for only a small percentage of all drugs in clinical use, which does not match the important roles of carbohydrates in the organism. In other words, carbohydrates are a relatively untapped source of new drugs and therefore may offer exciting novel therapeutic opportunities. Here, we presented an overview of the application of carbohydrates in approved small molecule drugs and emphasized and evaluated the roles of carbohydrates in those drugs. The potential development direction of carbohydrate-containing drugs was presented after summarizing the advantages and challenges of carbohydrates in the development of new drugs.
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Affiliation(s)
- Hongfei Jiang
- The Affiliated Hospital of Qingdao University, Qingdao University, Qingdao, 266071, China; Cancer Institute, Qingdao University, Qingdao, 266071, China
| | - Xiaofei Qin
- Department of Bioengineering, Zhuhai Campus of Zunyi Medical University, Zhuhai, 519041, China
| | - Qi Wang
- Department of Critical Medicine, Hainan Maternal and Children's Medical Center, Haikou, 570312, China
| | - Qi Xu
- Laboratory of Immunology for Environment and Health, Shandong Analysis and Test Center, Qilu University of Technology Shandong Academy of Sciences, Jinan, China
| | - Jie Wang
- Cancer Institute, Qingdao University, Qingdao, 266071, China
| | - Yudong Wu
- Cancer Institute, Qingdao University, Qingdao, 266071, China
| | - Wujun Chen
- Cancer Institute, Qingdao University, Qingdao, 266071, China
| | - Chao Wang
- Cancer Institute, Qingdao University, Qingdao, 266071, China
| | - Tingting Zhang
- Cancer Institute, Qingdao University, Qingdao, 266071, China
| | - Dongming Xing
- The Affiliated Hospital of Qingdao University, Qingdao University, Qingdao, 266071, China; Cancer Institute, Qingdao University, Qingdao, 266071, China; School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Renshuai Zhang
- The Affiliated Hospital of Qingdao University, Qingdao University, Qingdao, 266071, China; Cancer Institute, Qingdao University, Qingdao, 266071, China.
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4
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Schieweck R, Ninkovic J, Kiebler MA. RNA-binding proteins balance brain function in health and disease. Physiol Rev 2020; 101:1309-1370. [PMID: 33000986 DOI: 10.1152/physrev.00047.2019] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Posttranscriptional gene expression including splicing, RNA transport, translation, and RNA decay provides an important regulatory layer in many if not all molecular pathways. Research in the last decades has positioned RNA-binding proteins (RBPs) right in the center of posttranscriptional gene regulation. Here, we propose interdependent networks of RBPs to regulate complex pathways within the central nervous system (CNS). These are involved in multiple aspects of neuronal development and functioning, including higher cognition. Therefore, it is not sufficient to unravel the individual contribution of a single RBP and its consequences but rather to study and understand the tight interplay between different RBPs. In this review, we summarize recent findings in the field of RBP biology and discuss the complex interplay between different RBPs. Second, we emphasize the underlying dynamics within an RBP network and how this might regulate key processes such as neurogenesis, synaptic transmission, and synaptic plasticity. Importantly, we envision that dysfunction of specific RBPs could lead to perturbation within the RBP network. This would have direct and indirect (compensatory) effects in mRNA binding and translational control leading to global changes in cellular expression programs in general and in synaptic plasticity in particular. Therefore, we focus on RBP dysfunction and how this might cause neuropsychiatric and neurodegenerative disorders. Based on recent findings, we propose that alterations in the entire regulatory RBP network might account for phenotypic dysfunctions observed in complex diseases including neurodegeneration, epilepsy, and autism spectrum disorders.
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Affiliation(s)
- Rico Schieweck
- Biomedical Center (BMC), Department for Cell Biology and Anatomy, Medical Faculty, Ludwig-Maximilians-University, Planegg-Martinsried, Germany
| | - Jovica Ninkovic
- Biomedical Center (BMC), Department for Cell Biology and Anatomy, Medical Faculty, Ludwig-Maximilians-University, Planegg-Martinsried, Germany
| | - Michael A Kiebler
- Biomedical Center (BMC), Department for Cell Biology and Anatomy, Medical Faculty, Ludwig-Maximilians-University, Planegg-Martinsried, Germany
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5
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Tüting C, Iacobucci C, Ihling CH, Kastritis PL, Sinz A. Structural analysis of 70S ribosomes by cross-linking/mass spectrometry reveals conformational plasticity. Sci Rep 2020; 10:12618. [PMID: 32724211 PMCID: PMC7387497 DOI: 10.1038/s41598-020-69313-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Accepted: 07/10/2020] [Indexed: 12/14/2022] Open
Abstract
The ribosome is not only a highly complex molecular machine that translates the genetic information into proteins, but also an exceptional specimen for testing and optimizing cross-linking/mass spectrometry (XL-MS) workflows. Due to its high abundance, ribosomal proteins are frequently identified in proteome-wide XL-MS studies of cells or cell extracts. Here, we performed in-depth cross-linking of the E. coli ribosome using the amine-reactive cross-linker disuccinimidyl diacetic urea (DSAU). We analyzed 143 E. coli ribosomal structures, mapping a total of 10,771 intramolecular distances for 126 cross-link-pairs and 3,405 intermolecular distances for 97 protein pairs. Remarkably, 44% of intermolecular cross-links covered regions that have not been resolved in any high-resolution E. coli ribosome structure and point to a plasticity of cross-linked regions. We systematically characterized all cross-links and discovered flexible regions, conformational changes, and stoichiometric variations in bound ribosomal proteins, and ultimately remodeled 2,057 residues (15,794 atoms) in total. Our working model explains more than 95% of all cross-links, resulting in an optimized E. coli ribosome structure based on the cross-linking data obtained. Our study might serve as benchmark for conducting biochemical experiments on newly modeled protein regions, guided by XL-MS. Data are available via ProteomeXchange with identifier PXD018935.
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Affiliation(s)
- Christian Tüting
- Interdisciplinary Research Center HALOmem, Charles Tanford Protein Center, Martin Luther University Halle-Wittenberg, Kurt-Mothes-Str. 3a, 06120, Halle/Saale, Germany
| | - Claudio Iacobucci
- Department of Pharmaceutical Chemistry and Bioanalytics, Institute of Pharmacy, Charles Tanford Protein Center, Martin Luther University Halle-Wittenberg, Kurt-Mothes-Str. 3a, 06120, Halle/Saale, Germany
- Corporate Preclinical R&D, Analytics and Early Formulations Department, CHIESI FARMACEUTICI S.P.A., Via Palermo 26/A, 43122, Parma, Italy
| | - Christian H Ihling
- Department of Pharmaceutical Chemistry and Bioanalytics, Institute of Pharmacy, Charles Tanford Protein Center, Martin Luther University Halle-Wittenberg, Kurt-Mothes-Str. 3a, 06120, Halle/Saale, Germany
- Center for Structural Mass Spectrometry, Charles Tanford Protein Center, Martin Luther University Halle-Wittenberg, Kurt-Mothes-Str. 3a, 06120, Halle/Saale, Germany
| | - Panagiotis L Kastritis
- Interdisciplinary Research Center HALOmem, Charles Tanford Protein Center, Martin Luther University Halle-Wittenberg, Kurt-Mothes-Str. 3a, 06120, Halle/Saale, Germany.
- Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, Kurt-Mothes-Str. 3, 06120, Halle/Saale, Germany.
- Biozentrum, Martin Luther University Halle-Wittenberg, Weinbergweg 22, 06120, Halle/Saale, Germany.
| | - Andrea Sinz
- Department of Pharmaceutical Chemistry and Bioanalytics, Institute of Pharmacy, Charles Tanford Protein Center, Martin Luther University Halle-Wittenberg, Kurt-Mothes-Str. 3a, 06120, Halle/Saale, Germany.
- Center for Structural Mass Spectrometry, Charles Tanford Protein Center, Martin Luther University Halle-Wittenberg, Kurt-Mothes-Str. 3a, 06120, Halle/Saale, Germany.
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6
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Yang X, Tan J, Sun KH, Jiang L. Experimental demonstration of the importance of keystone communities for maintaining metacommunity biodiversity and ecosystem functioning. Oecologia 2020; 193:437-447. [PMID: 32556589 DOI: 10.1007/s00442-020-04693-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Accepted: 06/11/2020] [Indexed: 10/24/2022]
Abstract
As local communities within a metacommunity may differ considerably in their contributions to biodiversity and ecosystem functioning, it has been suggested that conservation priority should be given to disproportionately important local communities (i.e., keystone communities). However, we know little about what characterizes a keystone community. Using laboratory protist microcosms as the model system, we examined how the environmental uniqueness and location of a local community affect its contributions to the metacommunities. We found that the removal of local communities with unique environmental conditions, which supported endemic species, reduced regional-scale diversity, qualifying them as regional-scale keystone communities. In addition, the local communities possessing unique environmental conditions had greater impacts on ecosystem functions, including biovolume production and particulate organic matter decomposition. We also found that keystone communities for biovolume production were not keystone for organic matter decomposition, and vice versa. Our study, therefore, demonstrates the important role of keystone communities in maintaining biodiversity and functioning of metacommunities.
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Affiliation(s)
- Xian Yang
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | - Jiaqi Tan
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, 30332, USA.,Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, 15260, USA
| | | | - Lin Jiang
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, 30332, USA.
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7
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Waltz F, Corre N, Hashem Y, Giegé P. Specificities of the plant mitochondrial translation apparatus. Mitochondrion 2020; 53:30-37. [PMID: 32334144 DOI: 10.1016/j.mito.2020.04.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 04/14/2020] [Accepted: 04/21/2020] [Indexed: 12/16/2022]
Abstract
Mitochondria are endosymbiotic organelles responsible for energy production in most eukaryotic cells. They host a genome and a fully functional gene expression machinery. In plants this machinery involves hundreds of pentatricopeptide repeat (PPR) proteins. Translation, the final step of mitochondrial gene expression is performed by mitochondrial ribosomes (mitoribosomes). The nature of these molecular machines remained elusive for a very long time. Because of their bacterial origin, it was expected that mitoribosomes would closely resemble bacterial ribosomes. However, recent advances in cryo-electron microscopy have revealed the extraordinary diversity of mitoribosome structure and composition. The plant mitoribosome was characterized for Arabidopsis. In plants, in contrast to other species such as mammals and kinetoplastids where rRNA has been largely reduced, the mitoribosome could be described as a protein/RNA-augmented bacterial ribosome. It has an oversized small subunit formed by expanded ribosomal RNAs and additional protein components when compared to bacterial ribosomes. The same holds true for the large subunit. The small subunit is characterized by a new elongated domain on the head. Among its additional proteins, several PPR proteins are core mitoribosome proteins. They mainly act at the structural level to stabilize and maintain the plant-specific ribosomal RNA expansions but could also be involved in translation initiation. Recent advances in plant mitoribosome composition and structure, its specialization for membrane protein synthesis, translation initiation, the regulation and dynamics of mitochondrial translation are reviewed here and put in perspective with the diversity of mitochondrial translation processes in the green lineage and in the wider context of eukaryote evolution.
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Affiliation(s)
- Florent Waltz
- Institut Européen de Chimie et Biologie, U1212 Inserm, Université de Bordeaux, 2 rue R. Escarpit, F 33600 Pessac, France
| | - Nicolas Corre
- Institut de biologie de moléculaire des plantes, CNRS, Université de Strasbourg, 12 rue du général Zimmer, F 67084 Strasbourg, France
| | - Yaser Hashem
- Institut Européen de Chimie et Biologie, U1212 Inserm, Université de Bordeaux, 2 rue R. Escarpit, F 33600 Pessac, France
| | - Philippe Giegé
- Institut de biologie de moléculaire des plantes, CNRS, Université de Strasbourg, 12 rue du général Zimmer, F 67084 Strasbourg, France.
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8
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Čolović MB, Lacković M, Lalatović J, Mougharbel AS, Kortz U, Krstić DZ. Polyoxometalates in Biomedicine: Update and Overview. Curr Med Chem 2020; 27:362-379. [PMID: 31453779 DOI: 10.2174/0929867326666190827153532] [Citation(s) in RCA: 70] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Revised: 07/30/2019] [Accepted: 08/20/2019] [Indexed: 12/31/2022]
Abstract
BACKGROUND Polyoxometalates (POMs) are negatively charged metal-oxo clusters of early transition metal ions in high oxidation states (e.g., WVI, MoVI, VV). POMs are of interest in the fields of catalysis, electronics, magnetic materials and nanotechnology. Moreover, POMs were shown to exhibit biological activities in vitro and in vivo, such as antitumor, antimicrobial, and antidiabetic. METHODS The literature search for this peer-reviewed article was performed using PubMed and Scopus databases with the help of appropriate keywords. RESULTS This review gives a comprehensive overview of recent studies regarding biological activities of polyoxometalates, and their biomedical applications as promising anti-viral, anti-bacterial, anti-tumor, and anti-diabetic agents. Additionally, their putative mechanisms of action and molecular targets are particularly considered. CONCLUSION Although a wide range of biological activities of Polyoxometalates (POMs) has been reported, they are to the best of our knowledge not close to a clinical trial or a final application in the treatment of diabetes or infectious and malignant diseases. Accordingly, further studies should be directed towards determining the mechanism of POM biological actions, which would enable fine-tuning at the molecular level, and consequently efficient action towards biological targets and as low toxicity as possible. Furthermore, biomedical studies should be performed on solutionstable POMs employing physiological conditions and concentrations.
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Affiliation(s)
- Mirjana B Čolović
- Department of Physical Chemistry, "Vinca" Institute of Nuclear Sciences, University of Belgrade, Belgrade 11,000, Serbia
| | - Milan Lacković
- University Clinical Hospital Center dr Dragisa Misovic-Dedinje, Belgrade 11,000, Serbia
| | - Jovana Lalatović
- Faculty of Medicine, University of Belgrade, Belgrade 11,000, Serbia
| | - Ali S Mougharbel
- Department of Life Sciences and Chemistry, Jacobs University, Bremen, Germany
| | - Ulrich Kortz
- Department of Life Sciences and Chemistry, Jacobs University, Bremen, Germany
| | - Danijela Z Krstić
- Institute of Medical Chemistry, Faculty of Medicine, University of Belgrade, Belgrade 11,000, Serbia
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Thomas EN, Kim KQ, McHugh EP, Marcinkiewicz T, Zaher HS. Alkylative damage of mRNA leads to ribosome stalling and rescue by trans translation in bacteria. eLife 2020; 9:61984. [PMID: 32940602 PMCID: PMC7521929 DOI: 10.7554/elife.61984] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Accepted: 09/16/2020] [Indexed: 02/06/2023] Open
Abstract
Similar to DNA replication, translation of the genetic code by the ribosome is hypothesized to be exceptionally sensitive to small chemical changes to its template mRNA. Here we show that the addition of common alkylating agents to growing cultures of Escherichia coli leads to the accumulation of several adducts within RNA, including N(1)-methyladenosine (m1A). As expected, the introduction of m1A to model mRNAs was found to reduce the rate of peptide bond formation by three orders of magnitude in a well-defined in vitro system. These observations suggest that alkylative stress is likely to stall translation in vivo and necessitates the activation of ribosome-rescue pathways. Indeed, the addition of alkylation agents was found to robustly activate the transfer-messenger RNA system, even when transcription was inhibited. Our findings suggest that bacteria carefully monitor the chemical integrity of their mRNA and they evolved rescue pathways to cope with its effect on translation.
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Affiliation(s)
- Erica N Thomas
- Department of Biology, Washington University in St. LouisSt. LouisUnited States
| | - Kyusik Q Kim
- Department of Biology, Washington University in St. LouisSt. LouisUnited States
| | - Emily P McHugh
- Department of Biology, Washington University in St. LouisSt. LouisUnited States
| | | | - Hani S Zaher
- Department of Biology, Washington University in St. LouisSt. LouisUnited States
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10
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Fluorescence in situ hybridization (FISH) and cell sorting of living bacteria. Sci Rep 2019; 9:18618. [PMID: 31819112 PMCID: PMC6901588 DOI: 10.1038/s41598-019-55049-2] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Accepted: 11/21/2019] [Indexed: 01/09/2023] Open
Abstract
Despite the development of several cultivation methods, the rate of discovery of microorganisms that are yet-to-be cultivated outpaces the rate of isolating and cultivating novel species in the laboratory. Furthermore, no current cultivation technique is capable of selectively isolating and cultivating specific bacterial taxa or phylogenetic groups independently of morphological or physiological properties. Here, we developed a new method to isolate living bacteria solely based on their 16S rRNA gene sequence. We showed that bacteria can survive a modified version of the standard fluorescence in situ hybridization (FISH) procedure, in which fixation is omitted and other factors, such as centrifugation and buffers, are optimized. We also demonstrated that labelled DNA probes can be introduced into living bacterial cells by means of chemical transformation and that specific hybridization occurs. This new method, which we call live-FISH, was then combined with fluorescence-activated cell sorting (FACS) to sort specific taxonomic groups of bacteria from a mock and natural bacterial communities and subsequently culture them. Live-FISH represents the first attempt to systematically optimize conditions known to affect cell viability during FISH and then to sort bacterial cells surviving the procedure. No sophisticated probe design is required, making live-FISH a straightforward method to be potentially used in combination with other single-cell techniques and for the isolation and cultivation of new microorganisms.
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11
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Thomas EN, Simms CL, Keedy HE, Zaher HS. Insights into the base-pairing preferences of 8-oxoguanosine on the ribosome. Nucleic Acids Res 2019; 47:9857-9870. [PMID: 31400119 PMCID: PMC6765139 DOI: 10.1093/nar/gkz701] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 07/26/2019] [Accepted: 07/30/2019] [Indexed: 02/06/2023] Open
Abstract
Of the four bases, guanine is the most susceptible to oxidation, which results in the formation of 8-oxoguanine (8-oxoG). In protein-free DNA, 8-oxodG adopts the syn conformation more frequently than the anti one. In the syn conformation, 8-oxodG base pairs with dA. The equilibrium between the anti and syn conformations of the adduct are known to be altered by the enzyme recognizing 8-oxodG. We previously showed that 8-oxoG in mRNA severely disrupts tRNA selection, but the underlying mechanism for these effects was not addressed. Here, we use miscoding antibiotics and ribosome mutants to probe how 8-oxoG interacts with the tRNA anticodon in the decoding center. Addition of antibiotics and introduction of error-inducing mutations partially suppressed the effects of 8-oxoG. Under these conditions, rates and/or endpoints of peptide-bond formation for the cognate (8-oxoG•C) and near-cognate (8-oxoG•A) aminoacyl-tRNAs increased. In contrast, the antibiotics had little effect on other mismatches, suggesting that the lesion restricts the nucleotide from forming other interactions. Our findings suggest that 8-oxoG predominantly adopts the syn conformation in the A site. However, its ability to base pair with adenosine in this conformation is not sufficient to promote the necessary structural changes for tRNA selection to proceed.
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Affiliation(s)
- Erica N Thomas
- Department of Biology, Washington University in St. Louis, Campus Box 1137, One Brookings Drive, St. Louis, MO 63130, USA
| | - Carrie L Simms
- Department of Biology, Washington University in St. Louis, Campus Box 1137, One Brookings Drive, St. Louis, MO 63130, USA
| | - Hannah E Keedy
- Department of Biology, Washington University in St. Louis, Campus Box 1137, One Brookings Drive, St. Louis, MO 63130, USA
| | - Hani S Zaher
- Department of Biology, Washington University in St. Louis, Campus Box 1137, One Brookings Drive, St. Louis, MO 63130, USA
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12
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Sulima SO, Dinman JD. The Expanding Riboverse. Cells 2019; 8:cells8101205. [PMID: 31590378 PMCID: PMC6829380 DOI: 10.3390/cells8101205] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Revised: 09/25/2019] [Accepted: 10/03/2019] [Indexed: 12/13/2022] Open
Abstract
Subverting the conventional concept of “the” ribosome, a wealth of information gleaned from recent studies is revealing a much more diverse and dynamic ribosomal reality than has traditionally been thought possible. A diverse array of researchers is collectively illuminating a universe of heterogeneous and adaptable ribosomes harboring differences in composition and regulatory capacity: These differences enable specialization. The expanding universe of ribosomes not only comprises an incredible richness in ribosomal specialization between species, but also within the same tissues and even cells. In this review, we discuss ribosomal heterogeneity and speculate how the emerging understanding of the ribosomal repertoire is impacting the biological sciences today. Targeting pathogen-specific and pathological “diseased” ribosomes promises to provide new treatment options for patients, and potential applications for “designer ribosomes” are within reach. Our deepening understanding of and ability to manipulate the ribosome are establishing both the technological and theoretical foundations for major advances for the 21st century and beyond.
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Affiliation(s)
- Sergey O Sulima
- Biopharmaceutical New Technologies (BioNTech) Corporation, 55131 Mainz, Germany.
| | - Jonathan D Dinman
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742, USA .
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Abstract
The kink-turn (k-turn) is a widespread structural motif found in functional RNA species. It typically comprises a three-nucleotide bulge followed by tandem trans sugar edge-Hoogsteen G:A base pairs. It introduces a sharp kink into the axis of duplex RNA, juxtaposing the minor grooves. Cross-strand H-bonds form at the interface, accepted by the conserved adenine nucleobases of the G:A basepairs. Alternative acceptors for one of these divides the k-turns into two conformational classes N3 and N1. The base pair that follows the G:A pairs (3b:3n) determines which conformation is adopted by a given k-turn. k-turns often mediate tertiary contacts in folded RNA species and frequently bind proteins. Common k-turn binding proteins include members of the L7Ae family, such as the human 15·5k protein. A recognition helix within these proteins binds in the widened major groove on the outside of the k-turn, that makes specific H-bonds with the conserved guanine nucleobases of the G:A pairs. L7Ae binds with extremely high affinity, and single-molecule data are consistent with folding by conformational selection. The standard, simple k-turn can be elaborated in a variety of ways, that include the complex k-turns and the k-junctions. In free solution in the absence of added metal ions or protein k-turns do not adopt the tightly-kinked conformation. They undergo folding by the binding of proteins, by the formation of tertiary contacts, and some (but not all) will fold on the addition of metal ions. Whether or not folding occurs in the presence of metal ions depends on local sequence, including the 3b:3n position, and the -1b:-1n position (5' to the bulge). In most cases -1b:-1n = C:G, so that the 3b:3n position is critical since it determines both folding properties and conformation. In general, the selection of these sequence matches a given k-turn to its biological requirements. The k-turn structure is now very well understood, to the point at which they can be used as a building block for the formation of RNA nano-objects, including triangles and squares.
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14
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Investigating architecture and structure-function relationships in cold shock DNA-binding domain family using structural genomics-based approach. Int J Biol Macromol 2019; 133:484-494. [DOI: 10.1016/j.ijbiomac.2019.04.135] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 04/09/2019] [Accepted: 04/17/2019] [Indexed: 11/19/2022]
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15
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Thompson RD, Baisden JT, Zhang Q. NMR characterization of RNA small molecule interactions. Methods 2019; 167:66-77. [PMID: 31128236 DOI: 10.1016/j.ymeth.2019.05.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2019] [Revised: 05/17/2019] [Accepted: 05/17/2019] [Indexed: 01/25/2023] Open
Abstract
Exciting discoveries of naturally occurring ligand-sensing and disease-linked noncoding RNAs have promoted significant interests in understanding RNA-small molecule interactions. NMR spectroscopy is a powerful tool for characterizing intermolecular interactions. In this review, we describe protocols and approaches for applying NMR spectroscopy to investigate interactions between RNA and small molecules. We review protocols for RNA sample preparation, methods for identifying RNA-binding small molecules, approaches for mapping RNA-small molecule interactions, determining complex structures, and characterizing binding kinetics. We hope this review will provide a guideline to streamline NMR applications in studying RNA-small molecule interactions, facilitating both basic mechanistic understandings of RNA functions and translational efforts in developing RNA-targeted therapeutics.
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Affiliation(s)
- Rhese D Thompson
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Jared T Baisden
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Qi Zhang
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
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16
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Mustafi M, Weisshaar JC. Near Saturation of Ribosomal L7/L12 Binding Sites with Ternary Complexes in Slowly Growing E. coli. J Mol Biol 2019; 431:2343-2353. [PMID: 31051175 DOI: 10.1016/j.jmb.2019.04.037] [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: 01/17/2019] [Revised: 03/26/2019] [Accepted: 04/21/2019] [Indexed: 11/26/2022]
Abstract
For Escherichia coli growing rapidly in rich medium at 37 °C, the doubling time can be as short as ~20 min and the average rate of translation (ktrl) can be as fast as ~20 amino acids/s. For slower growth arising from poor nutrient quality or from higher growth osmolality, ktrl decreases significantly. In earlier work from the Hwa lab, a simplified Michaelis-Menten model suggested that the decrease in ktrl arises from a shortage of ternary complexes (TCs) under nutrient limitation and from slower diffusion of TCs under high growth osmolality. Here we present a single-molecule tracking study of the diffusion of EF-Tu in E. coli growing with doubling times in the range 62-190 min at 37 °C due to nutrient limitation, high growth osmolality, or both. The diffusive properties of EF-Tu remain quantitatively indistinguishable across all growth conditions studied. Dissection of the total population into ribosome-bound and free sub-populations, combined with copy number estimates for EF-Tu and ribosomes, indicates that in all cases ~3.7 EF-Tu copies are bound on average to each translating 70S ribosome. Thus, the four L7/L12 binding sites adjacent to the ribosomal A-site in E. coli are essentially saturated with TCs in all conditions, facilitating rapid testing of aminoacyl-tRNAs for a codon match. Evidently, the average translation rate is not limited by either the supply of cognate TCs under nutrient limitation or by the diffusion of free TCs at high osmolality. Some other step or steps must be rate limiting for translation in slow growth.
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Affiliation(s)
- Mainak Mustafi
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - James C Weisshaar
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53706, USA.
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17
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Aubert M, O'Donohue MF, Lebaron S, Gleizes PE. Pre-Ribosomal RNA Processing in Human Cells: From Mechanisms to Congenital Diseases. Biomolecules 2018; 8:biom8040123. [PMID: 30356013 PMCID: PMC6315592 DOI: 10.3390/biom8040123] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Revised: 10/19/2018] [Accepted: 10/19/2018] [Indexed: 12/15/2022] Open
Abstract
Ribosomal RNAs, the most abundant cellular RNA species, have evolved as the structural scaffold and the catalytic center of protein synthesis in every living organism. In eukaryotes, they are produced from a long primary transcript through an intricate sequence of processing steps that include RNA cleavage and folding and nucleotide modification. The mechanisms underlying this process in human cells have long been investigated, but technological advances have accelerated their study in the past decade. In addition, the association of congenital diseases to defects in ribosome synthesis has highlighted the central place of ribosomal RNA maturation in cell physiology regulation and broadened the interest in these mechanisms. Here, we give an overview of the current knowledge of pre-ribosomal RNA processing in human cells in light of recent progress and discuss how dysfunction of this pathway may contribute to the physiopathology of congenital diseases.
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Affiliation(s)
- Maxime Aubert
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 31000 Toulouse, France.
| | - Marie-Françoise O'Donohue
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 31000 Toulouse, France.
| | - Simon Lebaron
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 31000 Toulouse, France.
| | - Pierre-Emmanuel Gleizes
- Laboratoire de Biologie Moléculaire Eucaryote, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 31000 Toulouse, France.
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18
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Amir M, Kumar V, Dohare R, Islam A, Ahmad F, Hassan MI. Sequence, structure and evolutionary analysis of cold shock domain proteins, a member of OB fold family. J Evol Biol 2018; 31:1903-1917. [PMID: 30267552 DOI: 10.1111/jeb.13382] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2018] [Revised: 09/20/2018] [Accepted: 09/24/2018] [Indexed: 11/28/2022]
Abstract
The cold shock domain (CSD) belongs to the oligosaccharide/oligonucleotide-binding fold superfamily which is highly conserved from prokaryotes to higher eukaryotes, and appears to function as RNA chaperones. CSD is involved in diverse cellular processes, including adaptation to low temperatures, nutrient stress, cellular growth and developmental processes. Structural Classification of Proteins (SCOP) database broadly classifies OB fold proteins into 18 different superfamilies, including nucleic acid-binding superfamily (NAB). The NAB is further divided into 17 families together with cold shock DNA-binding protein family (CSDB). The CSDB have more than 240 000 sequences in UniProt database consisting of 32 domains including CSD. Among these domains, CSD is the second largest sequence contributor (> 40 398 sequences). Herein, we have systematically analysed the relative abundance and distribution of CSD proteins based on sequences, structures, repeats and gene ontology (GO) molecular functions in all domains of life. Analysis of sequence distribution suggesting that CSDs are largely found in bacteria (83-94%) with single CSD repeat. However, repeat distribution in eukaryota varies from 1 to 5 in combination with other auxiliary domain that makes CSD proteins functionally more diverse compared to the bacterial counterparts. Further, analysis of repeats distributions on evolutionary scale suggest that existence of CSD in multiple repeats is mainly driven through speciation, gene shuffling and gene duplication events.
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Affiliation(s)
- Mohd Amir
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi, India
| | - Vijay Kumar
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi, India.,Amity Institute of Neuropsychology & Neurosciences, Amity University Noida, UP, India
| | - Ravins Dohare
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi, India
| | - Asimul Islam
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi, India
| | - Faizan Ahmad
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi, India
| | - Md Imtaiyaz Hassan
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi, India
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19
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Shirokikh NE, Preiss T. Translation initiation by cap-dependent ribosome recruitment: Recent insights and open questions. WILEY INTERDISCIPLINARY REVIEWS-RNA 2018; 9:e1473. [PMID: 29624880 DOI: 10.1002/wrna.1473] [Citation(s) in RCA: 91] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Revised: 02/02/2018] [Accepted: 02/14/2018] [Indexed: 12/14/2022]
Abstract
Gene expression universally relies on protein synthesis, where ribosomes recognize and decode the messenger RNA template by cycling through translation initiation, elongation, and termination phases. All aspects of translation have been studied for decades using the tools of biochemistry and molecular biology available at the time. Here, we focus on the mechanism of translation initiation in eukaryotes, which is remarkably more complex than prokaryotic initiation and is the target of multiple types of regulatory intervention. The "consensus" model, featuring cap-dependent ribosome entry and scanning of mRNA leader sequences, represents the predominantly utilized initiation pathway across eukaryotes, although several variations of the model and alternative initiation mechanisms are also known. Recent advances in structural biology techniques have enabled remarkable molecular-level insights into the functional states of eukaryotic ribosomes, including a range of ribosomal complexes with different combinations of translation initiation factors that are thought to represent bona fide intermediates of the initiation process. Similarly, high-throughput sequencing-based ribosome profiling or "footprinting" approaches have allowed much progress in understanding the elongation phase of translation, and variants of them are beginning to reveal the remaining mysteries of initiation, as well as aspects of translation termination and ribosomal recycling. A current view on the eukaryotic initiation mechanism is presented here with an emphasis on how recent structural and footprinting results underpin axioms of the consensus model. Along the way, we further outline some contested mechanistic issues and major open questions still to be addressed. This article is categorized under: Translation > Translation Mechanisms Translation > Translation Regulation RNA Interactions with Proteins and Other Molecules > Protein-RNA Interactions: Functional Implications.
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Affiliation(s)
- Nikolay E Shirokikh
- EMBL-Australia Collaborating Group, Department of Genome Sciences, The John Curtin School of Medical Research, The Australian National University, Canberra, Australia
- Victor Chang Cardiac Research Institute, Darlinghurst, Australia
| | - Thomas Preiss
- EMBL-Australia Collaborating Group, Department of Genome Sciences, The John Curtin School of Medical Research, The Australian National University, Canberra, Australia
- Victor Chang Cardiac Research Institute, Darlinghurst, Australia
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20
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Abstract
Due to the availability of many macromolecular models in the Protein Data Bank, the majority of crystal structures are currently solved by molecular replacement. However, truly novel structures can only be solved by one of the versions of the special-atom method. The special atoms such as sulfur, phosphorus or metals could be naturally present in the macromolecules, or could be intentionally introduced in a derivatization process. The isomorphous and/or anomalous scattering of X-rays by these special atoms is then utilized for phasing. There are many ways to obtain potentially useful derivatives, ranging from the introduction of special atoms to proteins or nucleic acids by genetic engineering or by chemical synthesis, to soaking native crystals in solutions of appropriate compounds with heavy and/or anomalously scattering atoms. No approach guarantees the ultimate success and derivatization remains largely a trial-and-error process. In practice, however, there is a very good chance that one of a wide variety of the available procedures will lead to successful structure solution.
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21
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Abstract
In bacteria, elongation factor Tu is a translational cofactor that forms ternary complexes with aminoacyl-tRNA (aa-tRNA) and GTP. Binding of a ternary complex to one of four flexible L7/L12 units on the ribosome tethers a charged tRNA in close proximity to the ribosomal A site. Two sequential tests for a match between the aa-tRNA anticodon and the current mRNA codon then follow. Because one elongation cycle can occur in as little as 50 ms and the vast majority of aa-tRNA copies are not cognate with the current mRNA codon, this testing must occur rapidly. We present a single-molecule localization and tracking study of fluorescently labeled EF-Tu in live Escherichia coli. Imaging at 2 ms/frame distinguishes 60% slowly diffusing EF-Tu copies (assigned as transiently bound to translating ribosome) from 40% rapidly diffusing copies (assigned as a mixture of free ternary complexes and free EF-Tu). Combining these percentages with copy number estimates, we infer that the four L7/L12 sites are essentially saturated with ternary complexes in vivo. The results corroborate an earlier inference that all four sites can simultaneously tether ternary complexes near the A site, creating a high local concentration that may greatly enhance the rate of testing of aa-tRNAs. Our data and a combinatorial argument both suggest that the initial recognition test for a codon-anticodon match occurs in less than 1 to 2 ms per aa-tRNA copy. The results refute a recent study (A. Plochowietz, I. Farrell, Z. Smilansky, B. S. Cooperman, and A. N. Kapanidis, Nucleic Acids Res 45:926–937, 2016, https://doi.org/10.1093/nar/gkw787) of tRNA diffusion in E. coli that inferred that aa-tRNAs arrive at the ribosomal A site as bare monomers, not as ternary complexes. Ribosomes catalyze translation of the mRNA codon sequence into the corresponding sequence of amino acids within the nascent polypeptide chain. Polypeptide elongation can be as fast as 50 ms per added amino acid. Each amino acid arrives at the ribosome as a ternary complex comprising an aminoacyl-tRNA (aa-tRNA), an elongation factor called EF-Tu, and GTP. There are 43 different aa-tRNAs in use, only one of which typically matches the current mRNA codon. Thus, ternary complexes must be tested very rapidly. Here we use fluorescence-based single-molecule methods that locate and track single EF-Tu copies in E. coli. Fast and slow diffusive behavior determines the fraction of EF-Tu copies that are ribosome bound. We infer simultaneous tethering of ~4 ternary complexes to the ribosome, which may facilitate rapid initial testing for codon matching on a time scale of less than 1 to 2 ms per aa-tRNA.
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22
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Yusupova G, Yusupov M. Crystal structure of eukaryotic ribosome and its complexes with inhibitors. Philos Trans R Soc Lond B Biol Sci 2017; 372:rstb.2016.0184. [PMID: 28138070 DOI: 10.1098/rstb.2016.0184] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/16/2016] [Indexed: 01/26/2023] Open
Abstract
A high-resolution structure of the eukaryotic ribosome has been determined and has led to increased interest in studying protein biosynthesis and regulation of biosynthesis in cells. The functional complexes of the ribosome crystals obtained from bacteria and yeast have permitted researchers to identify the precise residue positions in different states of ribosome function. This knowledge, together with electron microscopy studies, enhances our understanding of how basic ribosome processes, including mRNA decoding, peptide bond formation, mRNA, and tRNA translocation and cotranslational transport of the nascent peptide, are regulated. In this review, we discuss the crystal structure of the entire 80S ribosome from yeast, which reveals its eukaryotic-specific features, and application of X-ray crystallography of the 80S ribosome for investigation of the binding mode for distinct compounds known to inhibit or modulate the protein-translation function of the ribosome. We also refer to a challenging aspect of the structural study of ribosomes, from higher eukaryotes, where the structures of major distinctive features of higher eukaryote ribosome-the high-eukaryote-specific long ribosomal RNA segments (about 1MDa)-remain unresolved. Presently, the structures of the major part of these high-eukaryotic expansion ribosomal RNA segments still remain unresolved.This article is part of the themed issue 'Perspectives on the ribosome'.
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Affiliation(s)
- Gulnara Yusupova
- Department of Integrated Structural Biology, Institute of Genetics and of Molecular and Cellular Biology, CNRS/INSERM, University of Strasbourg, BP 163, 67404 Illkirch Cedex, C.U. Strasbourg, France
| | - Marat Yusupov
- Department of Integrated Structural Biology, Institute of Genetics and of Molecular and Cellular Biology, CNRS/INSERM, University of Strasbourg, BP 163, 67404 Illkirch Cedex, C.U. Strasbourg, France
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23
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Davis JH, Williamson JR. Structure and dynamics of bacterial ribosome biogenesis. Philos Trans R Soc Lond B Biol Sci 2017; 372:rstb.2016.0181. [PMID: 28138067 DOI: 10.1098/rstb.2016.0181] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/16/2016] [Indexed: 01/28/2023] Open
Abstract
Bacterial ribosome biogenesis has been an active area of research for more than 30 years and has served as a test-bed for the development of new biochemical, biophysical and structural techniques to understand macromolecular assembly generally. Recent work inspecting the process in vivo has advanced our understanding of the role of ribosome biogenesis factors, the co-transcriptional nature of assembly, the kinetics of the process under sub-optimal conditions, and the rRNA folding and ribosome protein binding pathways. Additionally, new structural work enabled by single-particle electron microscopy has helped to connect in vitro ribosomal protein binding maps to the underlying RNA. This review summarizes the state of these in vivo studies, provides a kinetic model for ribosome assembly under sub-optimal conditions, and describes a framework to compare newly emerging assembly intermediate structures.This article is part of the themed issue 'Perspectives on the ribosome'.
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Affiliation(s)
- Joseph H Davis
- Department of Integrative Structural and Computational Biology, The Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA 92037, USA.,Department of Chemistry, The Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - James R Williamson
- Department of Integrative Structural and Computational Biology, The Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA 92037, USA .,Department of Chemistry, The Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
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24
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Gulay SP, Bista S, Varshney A, Kirmizialtin S, Sanbonmatsu KY, Dinman JD. Tracking fluctuation hotspots on the yeast ribosome through the elongation cycle. Nucleic Acids Res 2017; 45:4958-4971. [PMID: 28334755 PMCID: PMC5416885 DOI: 10.1093/nar/gkx112] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Accepted: 02/06/2017] [Indexed: 11/15/2022] Open
Abstract
Chemical modification was used to quantitatively determine the flexibility of nearly the entire rRNA component of the yeast ribosome through 8 discrete stages of translational elongation, revealing novel observations at the gross and fine-scales. These include (i) the bulk transfer of energy through the intersubunit bridges from the large to the small subunit after peptidyltransfer, (ii) differences in the interaction of the sarcin ricin loop with the two elongation factors and (iii) networked information exchange pathways that may functionally facilitate intra- and intersubunit coordination, including the 5.8S rRNA. These analyses reveal hot spots of fluctuations that set the stage for large-scale conformational changes essential for translocation and enable the first molecular dynamics simulation of an 80S complex. Comprehensive datasets of rRNA base flexibilities provide a unique resource to the structural biology community that can be computationally mined to complement ongoing research toward the goal of understanding the dynamic ribosome.
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Affiliation(s)
- Suna P Gulay
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742, USA
| | - Sujal Bista
- Department of Computer Science, University of Maryland, College Park, MD 20742, USA
| | - Amitabh Varshney
- Department of Computer Science, University of Maryland, College Park, MD 20742, USA
| | - Serdal Kirmizialtin
- Chemistry Program, New York University Abu Dhabi, Abu Dhabi, UAE.,The New Mexico Consortium, Los Alamos, NM 87544, USA
| | - Karissa Y Sanbonmatsu
- The New Mexico Consortium, Los Alamos, NM 87544, USA.,Theoretical Biology and Biophysics, Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - Jonathan D Dinman
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742, USA
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25
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Abstract
Major developments in cryo-electron microscopy in the past three or four years have led to the solution of a number of spliceosome structures at high resolution, e.g., the fully assembled but not yet active spliceosome (Bact), the spliceosome just after the first step of splicing (C), and the spliceosome activated for the second step (C*). Therefore 30 years of genetics and biochemistry of the spliceosome can now be interpreted at the structural level. I have closely examined the RNase H domain of Prp8 in each of the structures. Interestingly, the RNase H domain has different and unexpected roles in each of the catalytic steps of splicing.
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Affiliation(s)
- John Abelson
- Department of Biochemistry and Biophysics, University of California, San Francisco, CA 94143
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26
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Mwangi HN, Wagacha P, Mathenge P, Sijenyi F, Mulaa F. Structure of the 40S ribosomal subunit of Plasmodium falciparum by homology and de novo modeling. Acta Pharm Sin B 2017; 7:97-105. [PMID: 28119814 PMCID: PMC5237758 DOI: 10.1016/j.apsb.2016.10.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Revised: 06/13/2016] [Accepted: 09/05/2016] [Indexed: 01/21/2023] Open
Abstract
Generation of three dimensional structures of macromolecules using in silico structural modeling technologies such as homology and de novo modeling has improved dramatically and increased the speed by which tertiary structures of organisms can be generated. This is especially the case if a homologous crystal structure is already available. High-resolution structures can be rapidly created using only their sequence information as input, a process that has the potential to increase the speed of scientific discovery. In this study, homology modeling and structure prediction tools such as RNA123 and SWISS–MODEL were used to generate the 40S ribosomal subunit from Plasmodium falciparum. This structure was modeled using the published crystal structure from Tetrahymena thermophila, a homologous eukaryote. In the absence of the Plasmodium falciparum 40S ribosomal crystal structure, the model accurately depicts a global topology, secondary and tertiary connections, and gives an overall root mean square deviation (RMSD) value of 3.9 Å relative to the template׳s crystal structure. Deviations are somewhat larger in areas with no homology between the templates. These results demonstrate that this approach has the power to identify motifs of interest in RNA and identify potential drug targets for macromolecules whose crystal structures are unknown. The results also show the utility of RNA homology modeling software for structure determination and lay the groundwork for applying this approach to larger and more complex eukaryotic ribosomes and other RNA-protein complexes. Structures generated from this study can be used in in silico screening experiments and lead to the determination of structures for targets/hit complexes.
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27
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Batey RT, Kieft JS. Soaking Hexammine Cations into RNA Crystals to Obtain Derivatives for Phasing Diffraction Data. Methods Mol Biol 2016; 1320:219-32. [PMID: 26227046 DOI: 10.1007/978-1-4939-2763-0_14] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Solving a novel RNA structure by x-ray crystallography requires a means to obtain initial phase estimates. This is a challenge because many of the tools available for solving protein structures are not available for RNA. We have developed a reliable means to use hexammine cations to address this challenge. The process involves engineering the RNA to introduce a reliable hexammine binding site into the structure, then soaking crystals of these RNAs with an iridium (III) or cobalt (III) compound in a "directed soaking" strategy. Diffraction data obtained from these crystals then can be used in SAD or MAD phasing. In many cases, suitable derivatives can be obtained by soaking the hexammine into RNA crystals that have not been engineered. Considerations for using this method and example protocols are presented.
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Affiliation(s)
- Robert T Batey
- Department of Chemistry and Biochemistry, University of Colorado at Boulder, 596 UCB, Boulder, CO, 80309, USA,
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28
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Probing the Translation Dynamics of Ribosomes Using Zero-Mode Waveguides. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2015; 139:1-43. [PMID: 26970189 DOI: 10.1016/bs.pmbts.2015.10.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
In order to coordinate the complex biochemical and structural feat of converting triple-nucleotide codons into their corresponding amino acids, the ribosome must physically manipulate numerous macromolecules including the mRNA, tRNAs, and numerous translation factors. The ribosome choreographs binding, dissociation, physical movements, and structural rearrangements so that they synergistically harness the energy from biochemical processes, including numerous GTP hydrolysis steps and peptide bond formation. Due to the dynamic and complex nature of translation, the large cast of ligands involved, and the large number of possible configurations, tracking the global time evolution or dynamics of the ribosome complex in translation has proven to be challenging for bulk methods. Conventional single-molecule fluorescence experiments on the other hand require low concentrations of fluorescent ligands to reduce background noise. The significantly reduced bimolecular association rates under those conditions limit the number of steps that can be observed within the time window available to a fluorophore. The advent of zero-mode waveguide (ZMW) technology has allowed the study of translation at near-physiological concentrations of labeled ligands, moving single-molecule fluorescence microscopy beyond focused model systems into studying the global dynamics of translation in realistic setups. This chapter reviews the recent works using the ZMW technology to dissect the mechanism of translation initiation and elongation in prokaryotes, including complex processes such as translational stalling and frameshifting. Given the success of the technology, similarly complex biological processes could be studied in near-physiological conditions with the controllability of conventional in vitro experiments.
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29
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Abstract
The proteome of cells is synthesized by ribosomes, complex ribonucleoproteins that in eukaryotes contain 79-80 proteins and four ribosomal RNAs (rRNAs) more than 5,400 nucleotides long. How these molecules assemble together and how their assembly is regulated in concert with the growth and proliferation of cells remain important unanswered questions. Here, we review recently emerging principles to understand how eukaryotic ribosomal proteins drive ribosome assembly in vivo. Most ribosomal proteins assemble with rRNA cotranscriptionally; their association with nascent particles is strengthened as assembly proceeds. Each subunit is assembled hierarchically by sequential stabilization of their subdomains. The active sites of both subunits are constructed last, perhaps to prevent premature engagement of immature ribosomes with active subunits. Late-assembly intermediates undergo quality-control checks for proper function. Mutations in ribosomal proteins that affect mostly late steps lead to ribosomopathies, diseases that include a spectrum of cell type-specific disorders that often transition from hypoproliferative to hyperproliferative growth.
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Affiliation(s)
- Jesus de la Cruz
- Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocio/CSIC/Universidad de Sevilla, E-41013 Sevilla, Spain
- Departamento de Genetica, Universidad de Sevilla, E-41013 Sevilla, Spain
| | - Katrin Karbstein
- Department of Cancer Biology, The Scripps Research Institute, Jupiter, Florida 33458
| | - John L Woolford
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213
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30
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Verner Z, Basu S, Benz C, Dixit S, Dobáková E, Faktorová D, Hashimi H, Horáková E, Huang Z, Paris Z, Peña-Diaz P, Ridlon L, Týč J, Wildridge D, Zíková A, Lukeš J. Malleable mitochondrion of Trypanosoma brucei. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2015; 315:73-151. [PMID: 25708462 DOI: 10.1016/bs.ircmb.2014.11.001] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The importance of mitochondria for a typical aerobic eukaryotic cell is undeniable, as the list of necessary mitochondrial processes is steadily growing. Here, we summarize the current knowledge of mitochondrial biology of an early-branching parasitic protist, Trypanosoma brucei, a causative agent of serious human and cattle diseases. We present a comprehensive survey of its mitochondrial pathways including kinetoplast DNA replication and maintenance, gene expression, protein and metabolite import, major metabolic pathways, Fe-S cluster synthesis, ion homeostasis, organellar dynamics, and other processes. As we describe in this chapter, the single mitochondrion of T. brucei is everything but simple and as such rivals mitochondria of multicellular organisms.
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Affiliation(s)
- Zdeněk Verner
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Czech Republic; Present address: Faculty of Natural Sciences, Comenius University, Bratislava, Slovakia; Present address: Faculty of Sciences, Charles University, Prague, Czech Republic
| | - Somsuvro Basu
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Czech Republic; Faculty of Sciences, University of South Bohemia, České Budějovice (Budweis), Czech Republic; Present address: Institut für Zytobiologie und Zytopathologie, Philipps-Universität Marburg, Germany
| | - Corinna Benz
- Faculty of Sciences, University of South Bohemia, České Budějovice (Budweis), Czech Republic
| | - Sameer Dixit
- Faculty of Sciences, University of South Bohemia, České Budějovice (Budweis), Czech Republic
| | - Eva Dobáková
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Czech Republic; Present address: Faculty of Natural Sciences, Comenius University, Bratislava, Slovakia
| | - Drahomíra Faktorová
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Czech Republic; Faculty of Sciences, University of South Bohemia, České Budějovice (Budweis), Czech Republic
| | - Hassan Hashimi
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Czech Republic; Faculty of Sciences, University of South Bohemia, České Budějovice (Budweis), Czech Republic
| | - Eva Horáková
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Czech Republic
| | - Zhenqiu Huang
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Czech Republic; Faculty of Sciences, University of South Bohemia, České Budějovice (Budweis), Czech Republic
| | - Zdeněk Paris
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Czech Republic
| | - Priscila Peña-Diaz
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Czech Republic
| | - Lucie Ridlon
- Faculty of Sciences, University of South Bohemia, České Budějovice (Budweis), Czech Republic; Present address: Salk Institute, La Jolla, San Diego, USA
| | - Jiří Týč
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Czech Republic; Faculty of Sciences, University of South Bohemia, České Budějovice (Budweis), Czech Republic
| | - David Wildridge
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Czech Republic
| | - Alena Zíková
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Czech Republic; Faculty of Sciences, University of South Bohemia, České Budějovice (Budweis), Czech Republic
| | - Julius Lukeš
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Czech Republic; Faculty of Sciences, University of South Bohemia, České Budějovice (Budweis), Czech Republic
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Bijelic A, Molitor C, Mauracher SG, Al-Oweini R, Kortz U, Rompel A. Hen egg-white lysozyme crystallisation: protein stacking and structure stability enhanced by a Tellurium(VI)-centred polyoxotungstate. Chembiochem 2015; 16:233-41. [PMID: 25521080 PMCID: PMC4498469 DOI: 10.1002/cbic.201402597] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Indexed: 01/24/2023]
Abstract
As synchrotron radiation becomes more intense, detectors become faster and structure-solving software becomes more elaborate, obtaining single crystals suitable for data collection is now the bottleneck in macromolecular crystallography. Hence, there is a need for novel and advanced crystallisation agents with the ability to crystallise proteins that are otherwise challenging. Here, an Anderson-Evans-type polyoxometalate (POM), specifically Na6 [TeW6 O24 ]⋅22 H2 O (TEW), is employed as a crystallisation additive. Its effects on protein crystallisation are demonstrated with hen egg-white lysozyme (HEWL), which co-crystallises with TEW in the vicinity (or within) the liquid-liquid phase separation (LLPS) region. The X-ray structure (PDB ID: 4PHI) determination revealed that TEW molecules are part of the crystal lattice, thus demonstrating specific binding to HEWL with electrostatic interactions and hydrogen bonds. The negatively charged TEW polyoxotungstate binds to sites with a positive electrostatic potential located between two (or more) symmetry-related protein chains. Thus, TEW facilitates the formation of protein-protein interfaces of otherwise repulsive surfaces, and thereby the realisation of a stable crystal lattice. In addition to retaining the isomorphicity of the protein structure, the anomalous scattering of the POMs was used for macromolecular phasing. The results suggest that hexatungstotellurate(VI) has great potential as a crystallisation additive to promote both protein crystallisation and structure elucidation.
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Affiliation(s)
- Aleksandar Bijelic
- Institut für Biophysikalische Chemie, Fakultät für Chemie, Universität WienAlthanstrasse 14, 1090 Wien (Austria) E-mail:
| | - Christian Molitor
- Institut für Biophysikalische Chemie, Fakultät für Chemie, Universität WienAlthanstrasse 14, 1090 Wien (Austria) E-mail:
| | - Stephan G Mauracher
- Institut für Biophysikalische Chemie, Fakultät für Chemie, Universität WienAlthanstrasse 14, 1090 Wien (Austria) E-mail:
| | - Rami Al-Oweini
- School of Engineering and Science, Jacobs UniversityP. O. Box 750 561, 28725 Bremen (Germany)
| | - Ulrich Kortz
- School of Engineering and Science, Jacobs UniversityP. O. Box 750 561, 28725 Bremen (Germany)
| | - Annette Rompel
- Institut für Biophysikalische Chemie, Fakultät für Chemie, Universität WienAlthanstrasse 14, 1090 Wien (Austria) E-mail:
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Hong W, Zeng J, Xie J. Antibiotic drugs targeting bacterial RNAs. Acta Pharm Sin B 2014; 4:258-65. [PMID: 26579393 PMCID: PMC4629089 DOI: 10.1016/j.apsb.2014.06.012] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Revised: 06/04/2014] [Accepted: 06/20/2014] [Indexed: 10/26/2022] Open
Abstract
RNAs have diverse structures that include bulges and internal loops able to form tertiary contacts or serve as ligand binding sites. The recent increase in structural and functional information related to RNAs has put them in the limelight as a drug target for small molecule therapy. In addition, the recognition of the marked difference between prokaryotic and eukaryotic rRNA has led to the development of antibiotics that specifically target bacterial rRNA, reduce protein translation and thereby inhibit bacterial growth. To facilitate the development of new antibiotics targeting RNA, we here review the literature concerning such antibiotics, mRNA, riboswitch and tRNA and the key methodologies used for their screening.
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Affiliation(s)
| | | | - Jianping Xie
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Ministry of Education Eco-Environment of the Three Gorges Reservoir Region, School of Life Sciences, Southwest University, Chongqing 400715, China
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33
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Different subunits belonging to the same protein complex often exhibit discordant expression levels and evolutionary properties. Curr Opin Struct Biol 2014; 26:113-20. [DOI: 10.1016/j.sbi.2014.06.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Revised: 04/27/2014] [Accepted: 06/04/2014] [Indexed: 11/21/2022]
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Calidas D, Lyon H, Culver GM. The N-terminal extension of S12 influences small ribosomal subunit assembly in Escherichia coli. RNA (NEW YORK, N.Y.) 2014; 20:321-30. [PMID: 24442609 PMCID: PMC3923127 DOI: 10.1261/rna.042432.113] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
The small subunit (SSU) of the ribosome of E. coli consists of a core of ribosomal RNA (rRNA) surrounded peripherally by ribosomal proteins (r-proteins). Ten of the 15 universally conserved SSU r-proteins possess nonglobular regions called extensions. The N-terminal noncanonically structured extension of S12 traverses from the solvent to intersubunit surface of the SSU and is followed by a more C-terminal globular region that is adjacent to the decoding center of the SSU. The role of the globular region in maintaining translational fidelity is well characterized, but a role for the S12 extension in SSU structure and function is unknown. We examined the effect of stepwise truncation of the extension of S12 in SSU assembly and function in vitro and in vivo. Examination of in vitro assembly in the presence of sequential N-terminal truncated variants of S12 reveals that N-terminal deletions of greater than nine amino acids exhibit decreased tRNA-binding activity and altered 16S rRNA architecture particularly in the platform of the SSU. While wild-type S12 expressed from a plasmid can rescue a genomic deletion of the essential gene for S12, rpsl; N-terminal deletions of S12 exhibit deleterious phenotypic consequences. Partial N-terminal deletions of S12 are slow growing and cold sensitive. Strains bearing these truncations as the sole copy of S12 have increased levels of free SSUs and immature 16S rRNA as compared with the wild-type S12. These differences are hallmarks of SSU biogenesis defects, indicating that the extension of S12 plays an important role in SSU assembly.
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Affiliation(s)
- Deepika Calidas
- Department of Biology, Center for RNA Biology: From Genome to Therapeutics, University of Rochester Medical Center, Rochester, New York 14627, USA
| | - Hiram Lyon
- Department of Biology, Center for RNA Biology: From Genome to Therapeutics, University of Rochester Medical Center, Rochester, New York 14627, USA
| | - Gloria M. Culver
- Department of Biology, Center for RNA Biology: From Genome to Therapeutics, University of Rochester Medical Center, Rochester, New York 14627, USA
- Corresponding authorE-mail
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Abstract
The high-resolution structure of the eukaryotic ribosome from yeast, determined at 3.0-Å resolution, permitted the unambiguous determination of the protein side chains, eukaryote-specific proteins, protein insertions, and ribosomal RNA expansion segments of the 80 proteins and ∼5,500 RNA bases that constitute the 80S ribosome. A comparison between this first atomic model of the entire 80S eukaryotic ribosome and previously determined structures of bacterial ribosomes confirmed early genetic and structural data indicating that they share an evolutionarily conserved core of ribosomal RNA and proteins. It also confirmed the conserved organization of essential functional sites, such as the peptidyl transferase center and the decoding site. New structural information about eukaryote-specific elements, such as expansion segments and new ribosomal proteins, forms the structural framework for the design and analysis of experiments that will explore the eukaryotic translational apparatus and the evolutionary forces that shaped it. New nomenclature for ribosomal proteins, based on the names of protein families, has been proposed.
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Affiliation(s)
- Gulnara Yusupova
- Institut de Génétique et de Biologie Moléculaire et Cellulaire, Université de Strasbourg, Strasbourg F-67000, France
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36
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Mehta A, Sonam S, Gouri I, Loharch S, Sharma DK, Parkesh R. SMMRNA: a database of small molecule modulators of RNA. Nucleic Acids Res 2014; 42:D132-41. [PMID: 24163098 PMCID: PMC3965028 DOI: 10.1093/nar/gkt976] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2013] [Revised: 09/13/2013] [Accepted: 10/01/2013] [Indexed: 02/05/2023] Open
Abstract
We have developed SMMRNA, an interactive database, available at http://www.smmrna.org, with special focus on small molecule ligands targeting RNA. Currently, SMMRNA consists of ∼770 unique ligands along with structural images of RNA molecules. Each ligand in the SMMRNA contains information such as Kd, Ki, IC50, ΔTm, molecular weight (MW), hydrogen donor and acceptor count, XlogP, number of rotatable bonds, number of aromatic rings and 2D and 3D structures. These parameters can be explored using text search, advanced search, substructure and similarity-based analysis tools that are embedded in SMMRNA. A structure editor is provided for 3D visualization of ligands. Advance analysis can be performed using substructure and OpenBabel-based chemical similarity fingerprints. Upload facility for both RNA and ligands is also provided. The physicochemical properties of the ligands were further examined using OpenBabel descriptors, hierarchical clustering, binning partition and multidimensional scaling. We have also generated a 3D conformation database of ligands to support the structure and ligand-based screening. SMMRNA provides comprehensive resource for further design, development and refinement of small molecule modulators for selective targeting of RNA molecules.
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Affiliation(s)
- Ankita Mehta
- Department of Advanced Protein Science, Institute of Microbial Technology, Chandigarh-160036, India
| | - Surabhi Sonam
- Department of Advanced Protein Science, Institute of Microbial Technology, Chandigarh-160036, India
| | - Isha Gouri
- Department of Advanced Protein Science, Institute of Microbial Technology, Chandigarh-160036, India
| | - Saurabh Loharch
- Department of Advanced Protein Science, Institute of Microbial Technology, Chandigarh-160036, India
| | - Deepak K. Sharma
- Department of Advanced Protein Science, Institute of Microbial Technology, Chandigarh-160036, India
| | - Raman Parkesh
- Department of Advanced Protein Science, Institute of Microbial Technology, Chandigarh-160036, India
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37
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Demirci H, Wang L, Murphy FV, Murphy EL, Carr JF, Blanchard SC, Jogl G, Dahlberg AE, Gregory ST. The central role of protein S12 in organizing the structure of the decoding site of the ribosome. RNA (NEW YORK, N.Y.) 2013; 19:1791-801. [PMID: 24152548 PMCID: PMC3884664 DOI: 10.1261/rna.040030.113] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2013] [Accepted: 09/18/2013] [Indexed: 05/18/2023]
Abstract
The ribosome decodes mRNA by monitoring the geometry of codon-anticodon base-pairing using a set of universally conserved 16S rRNA nucleotides within the conformationally dynamic decoding site. By applying single-molecule FRET and X-ray crystallography, we have determined that conditional-lethal, streptomycin-dependence mutations in ribosomal protein S12 interfere with tRNA selection by allowing conformational distortions of the decoding site that impair GTPase activation of EF-Tu during the tRNA selection process. Distortions in the decoding site are reversed by streptomycin or by a second-site suppressor mutation in 16S rRNA. These observations encourage a refinement of the current model for decoding, wherein ribosomal protein S12 and the decoding site collaborate to optimize codon recognition and substrate discrimination during the early stages of the tRNA selection process.
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Affiliation(s)
- Hasan Demirci
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, Rhode Island 02912, USA
| | - Leyi Wang
- Department of Physiology and Biophysics, Weill Cornell Medical College of Cornell University, New York, New York 10021, USA
| | | | - Eileen L. Murphy
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, Rhode Island 02912, USA
| | - Jennifer F. Carr
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, Rhode Island 02912, USA
| | - Scott C. Blanchard
- Department of Physiology and Biophysics, Weill Cornell Medical College of Cornell University, New York, New York 10021, USA
| | - Gerwald Jogl
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, Rhode Island 02912, USA
| | - Albert E. Dahlberg
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, Rhode Island 02912, USA
| | - Steven T. Gregory
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, Rhode Island 02912, USA
- Corresponding authorE-mail
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38
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Espah Borujeni A, Channarasappa AS, Salis HM. Translation rate is controlled by coupled trade-offs between site accessibility, selective RNA unfolding and sliding at upstream standby sites. Nucleic Acids Res 2013; 42:2646-59. [PMID: 24234441 PMCID: PMC3936740 DOI: 10.1093/nar/gkt1139] [Citation(s) in RCA: 329] [Impact Index Per Article: 29.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The ribosome's interactions with mRNA govern its translation rate and the effects of post-transcriptional regulation. Long, structured 5' untranslated regions (5' UTRs) are commonly found in bacterial mRNAs, though the physical mechanisms that determine how the ribosome binds these upstream regions remain poorly defined. Here, we systematically investigate the ribosome's interactions with structured standby sites, upstream of Shine-Dalgarno sequences, and show that these interactions can modulate translation initiation rates by over 100-fold. We find that an mRNA's translation initiation rate is controlled by the amount of single-stranded surface area, the partial unfolding of RNA structures to minimize the ribosome's binding free energy penalty, the absence of cooperative binding and the potential for ribosomal sliding. We develop a biophysical model employing thermodynamic first principles and a four-parameter free energy model to accurately predict the ribosome's translation initiation rates for 136 synthetic 5' UTRs with large structures, diverse shapes and multiple standby site modules. The model predicts and experiments confirm that the ribosome can readily bind distant standby site modules that support high translation rates, providing a physical mechanism for observed context effects and long-range post-transcriptional regulation.
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Affiliation(s)
- Amin Espah Borujeni
- Department of Chemical Engineering, Penn State University, University Park, PA 16802, USA and Department of Agricultural and Biological Engineering, Penn State University, University Park, PA 16802, USA
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39
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Flores SC. Fast fitting to low resolution density maps: elucidating large-scale motions of the ribosome. Nucleic Acids Res 2013; 42:e9. [PMID: 24081579 PMCID: PMC3902909 DOI: 10.1093/nar/gkt906] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Determining the conformational rearrangements of large macromolecules is challenging experimentally and computationally. Case in point is the ribosome; it has been observed by high-resolution crystallography in several states, but many others are known only from low-resolution methods including cryo-electron microscopy. Combining these data into dynamical trajectories that may aid understanding of its largest-scale conformational changes has so far remained out of reach of computational methods. Most existing methods either model all atoms explicitly, resulting in often prohibitive cost, or use approximations that lose interesting structural and dynamical detail. In this work, I introduce Internal Coordinate Flexible Fitting, which uses full atomic forces and flexibility in limited regions of a model, capturing extensive conformational rearrangements at low cost. I use it to turn multiple low-resolution density maps, crystallographic structures and biochemical information into unified all-atoms trajectories of ribosomal translocation. Internal Coordinate Flexible Fitting is three orders of magnitude faster than the most comparable existing method.
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Affiliation(s)
- Samuel Coulbourn Flores
- Computational and Systems Biology Program, Department of Cell and Molecular Biology, Uppsala University, BMC Box 596, 75321 Uppsala, Sweden
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40
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Chan CW, Chetnani B, Mondragón A. Structure and function of the T-loop structural motif in noncoding RNAs. WILEY INTERDISCIPLINARY REVIEWS-RNA 2013; 4:507-22. [PMID: 23754657 DOI: 10.1002/wrna.1175] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2013] [Revised: 04/10/2013] [Accepted: 04/26/2013] [Indexed: 12/22/2022]
Abstract
The T-loop is a frequently occurring five-nucleotide motif found in the structure of noncoding RNAs where it is commonly assumed to play an important role in stabilizing the tertiary RNA structure by facilitating long-range interactions between different regions of the molecule. T-loops were first identified in tRNA(Phe) and a formal consensus sequence for this motif was formulated and later revised based on analyses of the crystal structures of prokaryotic ribosomal RNAs and RNase P and the corresponding primary sequence of their orthologues. In the past decade, several new structures of large RNA molecules have been added to the RCSB Protein Data Bank, including the eukaryotic ribosome, a self-splicing group II intron, numerous synthetases in complex with their cognate transfer RNAs (tRNAs), transfer-messenger RNA (tmRNA) in complex with SmpB, several riboswitches, and a complex of bacterial RNase P bound to its tRNA substrate. In this review, the search for T-loops is extended to these new RNA molecules based on the previously established structure-based criteria. The review highlights and discusses the function and additional roles of T-loops in four broad categories of RNA molecules, namely tRNAs, ribosomal RNAs (rRNAs), P RNAs, and RNA genetic elements. Additionally, the potential application for T-loops as interaction modules is also discussed.
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Affiliation(s)
- Clarence W Chan
- Department of Molecular Biosciences, Northwestern University, Evanston, IL, USA
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41
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Robinson CV. Finding the right balance - a personal journey from individual proteins to membrane-embedded motors. FEBS J 2012; 279:663-77. [DOI: 10.1111/j.1742-4658.2011.08460.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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42
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43
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Liljas A. The ribosome story: An overview of structural studies of protein synthesis on the ribosome. CRYSTALLOGR REV 2011. [DOI: 10.1080/0889311x.2011.587812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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44
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Collinet B, Friberg A, Brooks MA, van den Elzen T, Henriot V, Dziembowski A, Graille M, Durand D, Leulliot N, Saint André C, Lazar N, Sattler M, Séraphin B, van Tilbeurgh H. Strategies for the structural analysis of multi-protein complexes: lessons from the 3D-Repertoire project. J Struct Biol 2011; 175:147-58. [PMID: 21463689 DOI: 10.1016/j.jsb.2011.03.018] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2011] [Revised: 03/18/2011] [Accepted: 03/19/2011] [Indexed: 11/25/2022]
Abstract
Structural studies of multi-protein complexes, whether by X-ray diffraction, scattering, NMR spectroscopy or electron microscopy, require stringent quality control of the component samples. The inability to produce 'keystone' subunits in a soluble and correctly folded form is a serious impediment to the reconstitution of the complexes. Co-expression of the components offers a valuable alternative to the expression of single proteins as a route to obtain sufficient amounts of the sample of interest. Even in cases where milligram-scale quantities of purified complex of interest become available, there is still no guarantee that good quality crystals can be obtained. At this step, protein engineering of one or more components of the complex is frequently required to improve solubility, yield or the ability to crystallize the sample. Subsequent characterization of these constructs may be performed by solution techniques such as Small Angle X-ray Scattering and Nuclear Magnetic Resonance to identify 'well behaved' complexes. Herein, we recount our experiences gained at protein production and complex assembly during the European 3D Repertoire project (3DR). The goal of this consortium was to obtain structural information on multi-protein complexes from yeast by combining crystallography, electron microscopy, NMR and in silico modeling methods. We present here representative set case studies of complexes that were produced and analyzed within the 3DR project. Our experience provides useful insight into strategies that are more generally applicable for structural analysis of protein complexes.
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Affiliation(s)
- B Collinet
- IBBMC-CNRS UMR8619, IFR 115, Bât. 430, Université Paris-Sud, 91405 Orsay, France
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45
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Calidas D, Culver GM. Interdependencies govern multidomain architecture in ribosomal small subunit assembly. RNA (NEW YORK, N.Y.) 2011; 17:263-277. [PMID: 21156960 PMCID: PMC3022276 DOI: 10.1261/rna.2332511] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2010] [Accepted: 11/05/2010] [Indexed: 05/27/2023]
Abstract
The 30S subunit is composed of four structural domains, the body, platform, head, and penultimate/ultimate stems. The functional integrity of the 30S subunit is dependent upon appropriate assembly and precise orientation of all four domains. We examined 16S rRNA conformational changes during in vitro assembly using directed hydroxyl radical probing mediated by Fe(II)-derivatized ribosomal protein (r-protein) S8. R-protein S8 binds the central domain of 16S rRNA directly and independently and its iron derivatized substituents have been shown to mediate cleavage in three domains of 16S rRNA, thus making it an ideal probe to monitor multidomain orientation during assembly. Cleavages in minimal ribonucleoprotein (RNP) particles formed with Fe(II)-S8 and 16S rRNA alone were compared with that in the context of the fully assembled subunit. The minimal binding site of S8 at helix 21 exists in a structure similar to that observed in the mature subunit, in the absence of other r-proteins. However, the binding site of S8 at the junction of helices 25-26a, which is transcribed after helix 21, is cleaved with differing intensities in the presence and absence of other r-proteins. Also, assembly of the body helps establish an architecture approximating, but perhaps not identical, to the 30S subunit at helix 12 and the 5' terminus. Moreover, the assembly or orientation of the neck is dependent upon assembly of both the head and the body. Thus, a complex interrelationship is observed between assembly events of independent domains and the incorporation of primary binding proteins during 30S subunit formation.
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Affiliation(s)
- Deepika Calidas
- Department of Biology, University of Rochester, Rochester, New York 14627, USA
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46
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Rabl J, Leibundgut M, Ataide SF, Haag A, Ban N. Crystal structure of the eukaryotic 40S ribosomal subunit in complex with initiation factor 1. Science 2010; 331:730-6. [PMID: 21205638 DOI: 10.1126/science.1198308] [Citation(s) in RCA: 365] [Impact Index Per Article: 26.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Eukaryotic ribosomes are substantially larger and more complex than their bacterial counterparts. Although their core function is conserved, bacterial and eukaryotic protein synthesis differ considerably at the level of initiation. The eukaryotic small ribosomal subunit (40S) plays a central role in this process; it binds initiation factors that facilitate scanning of messenger RNAs and initiation of protein synthesis. We have determined the crystal structure of the Tetrahymena thermophila 40S ribosomal subunit in complex with eukaryotic initiation factor 1 (eIF1) at a resolution of 3.9 angstroms. The structure reveals the fold of the entire 18S ribosomal RNA and of all ribosomal proteins of the 40S subunit, and defines the interactions with eIF1. It provides insights into the eukaryotic-specific aspects of protein synthesis, including the function of eIF1 as well as signaling and regulation mediated by the ribosomal proteins RACK1 and rpS6e.
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Affiliation(s)
- Julius Rabl
- Institute of Molecular Biology and Biophysics, ETH Zürich, Schafmattstrasse 20, 8093 Zürich, Switzerland
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Armache JP, Jarasch A, Anger AM, Villa E, Becker T, Bhushan S, Jossinet F, Habeck M, Dindar G, Franckenberg S, Marquez V, Mielke T, Thomm M, Berninghausen O, Beatrix B, Söding J, Westhof E, Wilson DN, Beckmann R. Localization of eukaryote-specific ribosomal proteins in a 5.5-Å cryo-EM map of the 80S eukaryotic ribosome. Proc Natl Acad Sci U S A 2010; 107:19754-9. [PMID: 20974910 PMCID: PMC2993421 DOI: 10.1073/pnas.1010005107] [Citation(s) in RCA: 116] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Protein synthesis in all living organisms occurs on ribonucleoprotein particles, called ribosomes. Despite the universality of this process, eukaryotic ribosomes are significantly larger in size than their bacterial counterparts due in part to the presence of 80 r proteins rather than 54 in bacteria. Using cryoelectron microscopy reconstructions of a translating plant (Triticum aestivum) 80S ribosome at 5.5-Å resolution, together with a 6.1-Å map of a translating Saccharomyces cerevisiae 80S ribosome, we have localized and modeled 74/80 (92.5%) of the ribosomal proteins, encompassing 12 archaeal/eukaryote-specific small subunit proteins as well as the complete complement of the ribosomal proteins of the eukaryotic large subunit. Near-complete atomic models of the 80S ribosome provide insights into the structure, function, and evolution of the eukaryotic translational apparatus.
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Affiliation(s)
- Jean-Paul Armache
- Gene Center and Center for integrated Protein Science Munich, Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Strasse 25, 81377 Munich, Germany
| | - Alexander Jarasch
- Gene Center and Center for integrated Protein Science Munich, Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Strasse 25, 81377 Munich, Germany
| | - Andreas M. Anger
- Gene Center and Center for integrated Protein Science Munich, Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Strasse 25, 81377 Munich, Germany
| | - Elizabeth Villa
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany
| | - Thomas Becker
- Gene Center and Center for integrated Protein Science Munich, Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Strasse 25, 81377 Munich, Germany
| | - Shashi Bhushan
- Gene Center and Center for integrated Protein Science Munich, Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Strasse 25, 81377 Munich, Germany
| | - Fabrice Jossinet
- Université de Strasbourg, Institut de Biologie Moléculaire et Cellulaire du Centre National de la Recherche Scientifique, 15 Rue René Descartes, 67084 Strasbourg, France
| | - Michael Habeck
- Department of Empirical Inference, Max Planck Institute for Biological Cybernetics, Spemannstrasse 38, 72076 Tübingen, Germany
- Department of Protein Evolution, Max Planck Institute for Developmental Biology, Spemannstrasse 35, 72076 Tübingen, Germany
| | - Gülcin Dindar
- Gene Center and Center for integrated Protein Science Munich, Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Strasse 25, 81377 Munich, Germany
| | - Sibylle Franckenberg
- Gene Center and Center for integrated Protein Science Munich, Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Strasse 25, 81377 Munich, Germany
| | - Viter Marquez
- Gene Center and Center for integrated Protein Science Munich, Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Strasse 25, 81377 Munich, Germany
| | - Thorsten Mielke
- UltraStrukturNetzwerk, Max Planck Institute for Molecular Genetics, Ihnestrasse 73, 14195 Berlin, Germany
- Institut für Medizinische Physik und Biophysik, Charité, Ziegelstrasse 5-8, 10117 Berlin, Germany; and
| | - Michael Thomm
- Universität Regensburg, Lehrstuhl für Mikrobiologie, Universitätstrasse 31, 93053 Regensburg, Germany
| | - Otto Berninghausen
- Gene Center and Center for integrated Protein Science Munich, Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Strasse 25, 81377 Munich, Germany
| | - Birgitta Beatrix
- Gene Center and Center for integrated Protein Science Munich, Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Strasse 25, 81377 Munich, Germany
| | - Johannes Söding
- Gene Center and Center for integrated Protein Science Munich, Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Strasse 25, 81377 Munich, Germany
| | - Eric Westhof
- Université de Strasbourg, Institut de Biologie Moléculaire et Cellulaire du Centre National de la Recherche Scientifique, 15 Rue René Descartes, 67084 Strasbourg, France
| | - Daniel N. Wilson
- Gene Center and Center for integrated Protein Science Munich, Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Strasse 25, 81377 Munich, Germany
| | - Roland Beckmann
- Gene Center and Center for integrated Protein Science Munich, Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Strasse 25, 81377 Munich, Germany
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Song WS, Ryou SM, Kim HM, Jeon CO, Kim JM, Han SH, Kim SW, Szatkiewicz JP, Cunningham PR, Lee K. Functional investigation of residue G791 of Escherichia coli 16S rRNA: implication of initiation factor 1 in the restoration of P-site function. FEMS Microbiol Lett 2010; 313:141-7. [PMID: 21054500 DOI: 10.1111/j.1574-6968.2010.02137.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Using a specialized ribosome system, previous studies have identified G791 in Escherichia coli 16S rRNA as an invariant and essential residue for ribosome function. To investigate the functional role of G791, we searched for multicopy suppressors that partially restored the protein synthesis ability of mutant ribosomes bearing a G to U substitution at position 791 (U791 ribosomes). Analyses of isolated multicopy suppressors showed that overexpression of initiation factor 1 (IF1) enhanced the protein synthesis ability of U791 ribosomes. In contrast, overexpression of initiation factor 2 (IF2) or IF3 did not enhance the protein synthesis ability of wild-type or U791 ribosomes, and overexpression of IF1 did not affect the function of wild-type or mutant ribosomes bearing nucleotide substitutions in other regions of 16S rRNA. Analyses of sucrose gradient profiles of ribosomes showed that overexpression of IF1 marginally enhanced the subunit association of U791 ribosomes and indicated lower binding affinity of U791 ribosomes to IF1. Our findings suggest the involvement of IF1 in the restoration of the P-site function that was impaired by a nucleotide substitution at residue G791.
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Affiliation(s)
- Woo-Seok Song
- Department of Life Sciences (BK21 program), Chung-Ang University, Seoul, Korea
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49
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Cryo-EM structure and rRNA model of a translating eukaryotic 80S ribosome at 5.5-A resolution. Proc Natl Acad Sci U S A 2010; 107:19748-53. [PMID: 20980660 DOI: 10.1073/pnas.1009999107] [Citation(s) in RCA: 165] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Protein biosynthesis, the translation of the genetic code into polypeptides, occurs on ribonucleoprotein particles called ribosomes. Although X-ray structures of bacterial ribosomes are available, high-resolution structures of eukaryotic 80S ribosomes are lacking. Using cryoelectron microscopy and single-particle reconstruction, we have determined the structure of a translating plant (Triticum aestivum) 80S ribosome at 5.5-Å resolution. This map, together with a 6.1-Å map of a Saccharomyces cerevisiae 80S ribosome, has enabled us to model ∼98% of the rRNA. Accurate assignment of the rRNA expansion segments (ES) and variable regions has revealed unique ES-ES and r-protein-ES interactions, providing insight into the structure and evolution of the eukaryotic ribosome.
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50
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Ramakrishnan V. Unraveling the structure of the ribosome (Nobel Lecture). Angew Chem Int Ed Engl 2010; 49:4355-80. [PMID: 20535836 DOI: 10.1002/anie.201001436] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- V Ramakrishnan
- MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 0QH, UK
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