1
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Mou X, Liew SW, Kwok CK. Identification and targeting of G-quadruplex structures in MALAT1 long non-coding RNA. Nucleic Acids Res 2022; 50:397-410. [PMID: 34904666 PMCID: PMC8754639 DOI: 10.1093/nar/gkab1208] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2021] [Revised: 10/07/2021] [Accepted: 11/24/2021] [Indexed: 12/11/2022] Open
Abstract
RNA G-quadruplexes (rG4s) have functional roles in many cellular processes in diverse organisms. While a number of rG4 examples have been reported in coding messenger RNAs (mRNA), so far only limited works have studied rG4s in non-coding RNAs (ncRNAs), especially in long non-coding RNAs (lncRNAs) that are of emerging interest and significance in biology. Herein, we report that MALAT1 lncRNA contains conserved rG4 motifs, forming thermostable rG4 structures with parallel topology. We also show that rG4s in MALAT1 lncRNA can interact with NONO protein with high specificity and affinity in vitro and in nuclear cell lysate, and we provide cellular data to support that NONO protein recognizes MALAT1 lncRNA via rG4 motifs. Notably, we demonstrate that rG4s in MALAT1 lncRNA can be targeted by the rG4-specific small molecule, peptide, and L-aptamer, leading to the dissociation of MALAT1 rG4-NONO protein interaction. Altogether, this study uncovers new and important rG4s in MALAT1 lncRNAs, reveals their specific interactions with NONO protein, offers multiple strategies for targeting MALAT1 and its RNA-protein complex via its rG4 structure and illustrates the prevalence and significance of rG4s in ncRNAs.
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Affiliation(s)
- Xi Mou
- Department of Chemistry and State Key Laboratory of Marine Pollution, City
University of Hong Kong, Kowloon Tong, Hong Kong
SAR, China
| | - Shiau Wei Liew
- Department of Chemistry and State Key Laboratory of Marine Pollution, City
University of Hong Kong, Kowloon Tong, Hong Kong
SAR, China
| | - Chun Kit Kwok
- Department of Chemistry and State Key Laboratory of Marine Pollution, City
University of Hong Kong, Kowloon Tong, Hong Kong
SAR, China
- Shenzhen Research Institute of City University of Hong Kong,
Shenzhen, China
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2
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Zhang Y, Cheng Y, Chen J, Zheng K, You H. Mechanical diversity and folding intermediates of parallel-stranded G-quadruplexes with a bulge. Nucleic Acids Res 2021; 49:7179-7188. [PMID: 34139007 PMCID: PMC8266575 DOI: 10.1093/nar/gkab531] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 05/17/2021] [Accepted: 06/09/2021] [Indexed: 12/17/2022] Open
Abstract
A significant number of sequences in the human genome form noncanonical G-quadruplexes (G4s) with bulges or a guanine vacancy. Here, we systematically characterized the mechanical stability of parallel-stranded G4s with a one to seven nucleotides bulge at various positions. Our results show that G4-forming sequences with a bulge form multiple conformations, including fully-folded G4 with high mechanical stability (unfolding forces > 40 pN), partially-folded intermediates (unfolding forces < 40 pN). The folding probability and folded populations strongly depend on the positions and lengths of the bulge. By combining a single-molecule unfolding assay, dimethyl sulfate (DMS) footprinting, and a guanine-peptide conjugate that selectively stabilizes guanine-vacancy-bearing G-quadruplexes (GVBQs), we identified that GVBQs are the major intermediates of G4s with a bulge near the 5′ or 3′ ends. The existence of multiple structures may induce different regulatory functions in many biological processes. This study also demonstrates a new strategy for selectively stabilizing the intermediates of bulged G4s to modulate their functions.
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Affiliation(s)
- Yashuo Zhang
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Yuanlei Cheng
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Juannan Chen
- School of Pharmaceutical Sciences (Shenzhen), Sun Yat-Sen University, Guangzhou 510275, China
| | - Kewei Zheng
- School of Pharmaceutical Sciences (Shenzhen), Sun Yat-Sen University, Guangzhou 510275, China
| | - Huijuan You
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
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3
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Jana J, Mohr S, Vianney YM, Weisz K. Structural motifs and intramolecular interactions in non-canonical G-quadruplexes. RSC Chem Biol 2021; 2:338-353. [PMID: 34458788 PMCID: PMC8341446 DOI: 10.1039/d0cb00211a] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Accepted: 01/14/2021] [Indexed: 12/12/2022] Open
Abstract
Guanine(G)-rich DNA or RNA sequences can assemble or intramolecularly fold into G-quadruplexes formed through the stacking of planar G·G·G·G tetrads in the presence of monovalent cations. These secondary nucleic acid structures have convincingly been shown to also exist within a cellular environment exerting important regulatory functions in physiological processes. For identifying nucleic acid segments prone to quadruplex formation, a putative quadruplex sequence motif encompassing closely spaced tracts of three or more guanosines is frequently employed for bioinformatic search algorithms. Depending on the number and type of intervening residues as well as on solution conditions, such sequences may fold into various canonical G4 topologies with continuous G-columns. On the other hand, a growing number of sequences capable of quadruplex formation feature G-deficient guanine tracts, escaping the conservative consensus motif. By folding into non-canonical quadruplex structures, they adopt unique topologies depending on their specific sequence context. These include G-columns with only two guanines, bulges, snapback loops, D- and V-shaped loops as well as interlocked structures. This review focuses on G-quadruplex species carrying such distinct structural motifs. It evaluates characteristic features of their non-conventional scaffold and highlights principles of stabilizing interactions that also allow for their folding into stable G-quadruplex structures.
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Affiliation(s)
- Jagannath Jana
- Institute of Biochemistry, Universität Greifswald Felix-Hausdorff-Str. 4 D-17487 Greifswald Germany +49 3834 420-4427 +49 3834 420-4426
| | - Swantje Mohr
- Institute of Biochemistry, Universität Greifswald Felix-Hausdorff-Str. 4 D-17487 Greifswald Germany +49 3834 420-4427 +49 3834 420-4426
| | - Yoanes Maria Vianney
- Institute of Biochemistry, Universität Greifswald Felix-Hausdorff-Str. 4 D-17487 Greifswald Germany +49 3834 420-4427 +49 3834 420-4426
| | - Klaus Weisz
- Institute of Biochemistry, Universität Greifswald Felix-Hausdorff-Str. 4 D-17487 Greifswald Germany +49 3834 420-4427 +49 3834 420-4426
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4
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Das P, Ngo KH, Winnerdy FR, Maity A, Bakalar B, Mechulam Y, Schmitt E, Phan AT. Bulges in left-handed G-quadruplexes. Nucleic Acids Res 2021; 49:1724-1736. [PMID: 33503265 PMCID: PMC7897477 DOI: 10.1093/nar/gkaa1259] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 12/10/2020] [Accepted: 12/18/2020] [Indexed: 12/03/2022] Open
Abstract
G-quadruplex (G4) DNA structures with a left-handed backbone progression have unique and conserved structural features. Studies on sequence dependency of the structures revealed the prerequisites and some minimal motifs required for left-handed G4 formation. To extend the boundaries, we explore the adaptability of left-handed G4s towards the existence of bulges. Here we present two X-ray crystal structures and an NMR solution structure of left-handed G4s accommodating one, two and three bulges. Bulges in left-handed G4s show distinct characteristics as compared to those in right-handed G4s. The elucidation of intricate structural details will help in understanding the possible roles and limitations of these unique structures.
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Affiliation(s)
- Poulomi Das
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Khac Huy Ngo
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Fernaldo Richtia Winnerdy
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Arijit Maity
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Blaž Bakalar
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Yves Mechulam
- Laboratoire de Biologie Structurale de la Cellule (BIOC), Ecole Polytechnique, CNRS-UMR7654, Institut Polytechnique de Paris, Palaiseau 91128, France
| | - Emmanuelle Schmitt
- Laboratoire de Biologie Structurale de la Cellule (BIOC), Ecole Polytechnique, CNRS-UMR7654, Institut Polytechnique de Paris, Palaiseau 91128, France
| | - Anh Tuân Phan
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore.,NTU Institute of Structural Biology, Nanyang Technological University, Singapore 636921, Singapore
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5
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Sanchez-Martin V, Lopez-Pujante C, Soriano-Rodriguez M, Garcia-Salcedo JA. An Updated Focus on Quadruplex Structures as Potential Therapeutic Targets in Cancer. Int J Mol Sci 2020; 21:ijms21238900. [PMID: 33255335 PMCID: PMC7734589 DOI: 10.3390/ijms21238900] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 11/13/2020] [Accepted: 11/20/2020] [Indexed: 02/06/2023] Open
Abstract
Non-canonical, four-stranded nucleic acids secondary structures are present within regulatory regions in the human genome and transcriptome. To date, these quadruplex structures include both DNA and RNA G-quadruplexes, formed in guanine-rich sequences, and i-Motifs, found in cytosine-rich sequences, as their counterparts. Quadruplexes have been extensively associated with cancer, playing an important role in telomere maintenance and control of genetic expression of several oncogenes and tumor suppressors. Therefore, quadruplex structures are considered attractive molecular targets for cancer therapeutics with novel mechanisms of action. In this review, we provide a general overview about recent research on the implications of quadruplex structures in cancer, firstly gathering together DNA G-quadruplexes, RNA G-quadruplexes as well as DNA i-Motifs.
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Affiliation(s)
- Victoria Sanchez-Martin
- GENYO, Centre for Genomics and Oncological Research, Pfizer/University of Granada/Andalusian Regional Government, PTS Granada, 18016 Granada, Spain; (V.S.-M.); (C.L.-P.)
- Microbiology Unit, University Hospital Virgen de las Nieves, Biosanitary Research Institute IBS, Granada, 18014 Granada, Spain
- Department of Biochemistry, Molecular Biology III and Immunology, University of Granada, 18016 Granada, Spain
| | - Carmen Lopez-Pujante
- GENYO, Centre for Genomics and Oncological Research, Pfizer/University of Granada/Andalusian Regional Government, PTS Granada, 18016 Granada, Spain; (V.S.-M.); (C.L.-P.)
| | - Miguel Soriano-Rodriguez
- GENYO, Centre for Genomics and Oncological Research, Pfizer/University of Granada/Andalusian Regional Government, PTS Granada, 18016 Granada, Spain; (V.S.-M.); (C.L.-P.)
- Centre for Intensive Mediterranean Agrosystems and Agri-food Biotechnology (CIAMBITAL), University of Almeria, 04001 Almeria, Spain
- Correspondence: (M.S.-R.); (J.A.G.-S.); Tel.: +34-958715500 (M.S.-R.); +34-958715500 (J.A.G.-S.)
| | - Jose A. Garcia-Salcedo
- GENYO, Centre for Genomics and Oncological Research, Pfizer/University of Granada/Andalusian Regional Government, PTS Granada, 18016 Granada, Spain; (V.S.-M.); (C.L.-P.)
- Microbiology Unit, University Hospital Virgen de las Nieves, Biosanitary Research Institute IBS, Granada, 18014 Granada, Spain
- Correspondence: (M.S.-R.); (J.A.G.-S.); Tel.: +34-958715500 (M.S.-R.); +34-958715500 (J.A.G.-S.)
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6
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Ngoc Nguyen TQ, Lim KW, Phan AT. Duplex formation in a G-quadruplex bulge. Nucleic Acids Res 2020; 48:10567-10575. [PMID: 32960213 PMCID: PMC7544226 DOI: 10.1093/nar/gkaa738] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 08/21/2020] [Accepted: 08/31/2020] [Indexed: 01/05/2023] Open
Abstract
Beyond the consensus definition of G-quadruplex-forming motifs with tracts of continuous guanines, G-quadruplexes harboring bulges in the G-tetrad core are prevalent in the human genome. Here, we study the incorporation of a duplex hairpin within a bulge of a G-quadruplex. The NMR solution structure of a G-quadruplex containing a duplex bulge was resolved, revealing the structural details of the junction between the duplex bulge and the G-quadruplex. Unexpectedly, instead of an orthogonal connection the duplex stem was observed to stack below the G-quadruplex forming a unique quadruplex–duplex junction. Breaking up of the immediate base pair step at the junction, coupled with a narrowing of the duplex groove within the context of the bulge, led to a progressive transition between the quadruplex and duplex segments. This study revealed that a duplex bulge can be formed at various positions of a G-quadruplex scaffold. In contrast to a non-structured bulge, the stability of a G-quadruplex slightly increases with an increase in the duplex bulge size. A G-quadruplex structure containing a duplex bulge of up to 33 nt in size was shown to form, which was much larger than the previously reported 7-nt bulge. With G-quadruplexes containing duplex bulges representing new structural motifs with potential biological significance, our findings would broaden the definition of potential G-quadruplex-forming sequences.
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Affiliation(s)
- Thi Quynh Ngoc Nguyen
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Kah Wai Lim
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Anh Tuân Phan
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore.,NTU Institute of Structural Biology, Nanyang Technological University, Singapore 636921, Singapore
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7
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Umar MI, Kwok CK. Specific suppression of D-RNA G-quadruplex-protein interaction with an L-RNA aptamer. Nucleic Acids Res 2020; 48:10125-10141. [PMID: 32976590 PMCID: PMC7544233 DOI: 10.1093/nar/gkaa759] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 08/28/2020] [Accepted: 09/04/2020] [Indexed: 02/06/2023] Open
Abstract
G-quadruplexes (G4s) are nucleic acid structure motifs that are of significance in chemistry and biology. The function of G4s is often governed by their interaction with G4-binding proteins. Few categories of G4-specific tools have been developed to inhibit G4-protein interactions; however, until now there is no aptamer tool being developed to do so. Herein, we present a novel L-RNA aptamer that can generally bind to D-RNA G-quadruplex (rG4) structure, and interfere with rG4-protein interaction. Using hTERC rG4 as the target for in vitro selection, we report the shortest L-aptamer being developed so far, with only 25 nucleotides. Notably, this new aptamer, L-Apt.4-1c, adopts a stem-loop structure with the loop folding into an rG4 motif with two G-quartet, demonstrates preferential binding toward rG4s over non-G4s and DNA G-quadruplexes (dG4s), and suppresses hTERC rG4-nucleolin interactions. We also show that inhibition of rG4-protein interaction using L-RNA aptamer L-Apt.4-1c is comparable to or better than G4-specific ligands such as carboxypyridostatin and QUMA-1 respectively, highlighting that our approach and findings expand the current G4 toolbox, and open a new avenue for diverse applications.
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Affiliation(s)
- Mubarak I Umar
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong, Hong Kong SAR, China
| | - Chun Kit Kwok
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong, Hong Kong SAR, China
- Shenzhen Research Institute of City University of Hong Kong, Shenzhen, China
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8
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Chan C, Kwok CK. Specific Binding of a
d
‐RNA G‐Quadruplex Structure with an
l
‐RNA Aptamer. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.201914955] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Chun‐Yin Chan
- Department of ChemistryCity University of Hong Kong Tat Chee Avenue Kowloon Tong, Hong Kong SAR China
| | - Chun Kit Kwok
- Department of ChemistryCity University of Hong Kong Tat Chee Avenue Kowloon Tong, Hong Kong SAR China
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9
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Chan CY, Kwok CK. Specific Binding of a d-RNA G-Quadruplex Structure with an l-RNA Aptamer. Angew Chem Int Ed Engl 2020; 59:5293-5297. [PMID: 31975549 DOI: 10.1002/anie.201914955] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2019] [Revised: 01/06/2020] [Indexed: 01/24/2023]
Abstract
G-quadruplex (G4) structures are of general importance in chemistry and biology, such as in biosensing, gene regulation, and cancers. Although a large repertoire of G4-binding tools has been developed, no aptamer has been developed to interact with G4. Moreover, the G4 selectivity of current toolkits is very limited. Herein, we report the first l-RNA aptamer that targets a d-RNA G-quadruplex (rG4). Using TERRA rG4 as an example, our results reveal that this l-RNA aptamer, Ap3-7, folds into a unique secondary structure, exhibits high G4 selectivity and effectively interferes with TERRA-rG4-RHAU53 binding. Our approach and findings open a new door in further developing G4-specific tools for diverse applications.
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Affiliation(s)
- Chun-Yin Chan
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong, Hong Kong SAR, China
| | - Chun Kit Kwok
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong, Hong Kong SAR, China
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10
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Heddi B, Cheong VV, Schmitt E, Mechulam Y, Phan AT. Recognition of different base tetrads by RHAU (DHX36): X-ray crystal structure of the G4 recognition motif bound to the 3′-end tetrad of a DNA G-quadruplex. J Struct Biol 2020; 209:107399. [DOI: 10.1016/j.jsb.2019.10.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 09/30/2019] [Accepted: 10/02/2019] [Indexed: 12/16/2022]
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11
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Mestre-Fos S, Penev PI, Richards JC, Dean WL, Gray RD, Chaires JB, Williams LD. Profusion of G-quadruplexes on both subunits of metazoan ribosomes. PLoS One 2019; 14:e0226177. [PMID: 31834895 PMCID: PMC6910669 DOI: 10.1371/journal.pone.0226177] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Accepted: 11/03/2019] [Indexed: 01/17/2023] Open
Abstract
Mammalian and bird ribosomes are nearly twice the mass of prokaryotic ribosomes in part because of their extraordinarily long rRNA tentacles. Human rRNA tentacles are not fully observable in current three-dimensional structures and their conformations remain to be fully resolved. In previous work we identified sequences that favor G-quadruplexes in silico and in vitro in rRNA tentacles of the human large ribosomal subunit. We demonstrated by experiment that these sequences form G-quadruplexes in vitro. Here, using a more recent motif definition, we report additional G-quadruplex sequences on surfaces of both subunits of the human ribosome. The revised sequence definition reveals expansive arrays of potential G-quadruplex sequences on LSU tentacles. In addition, we demonstrate by a variety of experimental methods that fragments of the small subunit rRNA form G-quadruplexes in vitro. Prior to this report rRNA sequences that form G-quadruplexes were confined to the large ribosomal subunit. Our combined results indicate that the surface of the assembled human ribosome contains numerous sequences capable of forming G-quadruplexes on both ribosomal subunits. The data suggest conversion between duplexes and G-quadruplexes in response to association with proteins, ions, or other RNAs. In some systems it seems likely that the integrated population of RNA G-quadruplexes may be dominated by rRNA, which is the most abundant cellular RNA.
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Affiliation(s)
- Santi Mestre-Fos
- Center for the Origin of Life, Georgia Institute of Technology, Atlanta, Georgia, United States of America
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia, United States of America
| | - Petar I. Penev
- Center for the Origin of Life, Georgia Institute of Technology, Atlanta, Georgia, United States of America
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia, United States of America
| | - John Colin Richards
- Center for the Origin of Life, Georgia Institute of Technology, Atlanta, Georgia, United States of America
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia, United States of America
| | - William L. Dean
- James Graham Brown Cancer Center, University of Louisville, Louisville, Kentucky, United States of America
| | - Robert D. Gray
- James Graham Brown Cancer Center, University of Louisville, Louisville, Kentucky, United States of America
| | - Jonathan B. Chaires
- James Graham Brown Cancer Center, University of Louisville, Louisville, Kentucky, United States of America
| | - Loren Dean Williams
- Center for the Origin of Life, Georgia Institute of Technology, Atlanta, Georgia, United States of America
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia, United States of America
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia, United States of America
- * E-mail:
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12
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Lightfoot HL, Hagen T, Tatum NJ, Hall J. The diverse structural landscape of quadruplexes. FEBS Lett 2019; 593:2083-2102. [PMID: 31325371 DOI: 10.1002/1873-3468.13547] [Citation(s) in RCA: 86] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2019] [Revised: 07/09/2019] [Accepted: 07/15/2019] [Indexed: 12/15/2022]
Abstract
G-quadruplexes are secondary structures formed in G-rich sequences in DNA and RNA. Considerable research over the past three decades has led to in-depth insight into these unusual structures in DNA. Since the more recent exploration into RNA G-quadruplexes, such structures have demonstrated their in cellulo existence, function and roles in pathology. In comparison to Watson-Crick-based secondary structures, most G-quadruplexes display highly redundant structural characteristics. However, numerous reports of G-quadruplex motifs/structures with unique features (e.g. bulges, long loops, vacancy) have recently surfaced, expanding the repertoire of G-quadruplex scaffolds. This review addresses G-quadruplex formation and structure, including recent reports of non-canonical G-quadruplex structures. Improved methods of detection will likely further expand this collection of novel structures and ultimately change the face of quadruplex-RNA targeting as a therapeutic strategy.
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Affiliation(s)
- Helen L Lightfoot
- Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, ETH Zurich, Switzerland
| | - Timo Hagen
- Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, ETH Zurich, Switzerland
| | - Natalie J Tatum
- Newcastle Cancer Centre, Northern Institute for Cancer Research, Medical School, Newcastle University, Newcastle upon Tyne, UK
| | - Jonathan Hall
- Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, ETH Zurich, Switzerland
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13
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Cui X, Chen H, Zhang Q, Xu M, Yuan G, Zhou J. Exploration of the Structure and Recognition of a G-quadruplex in the her2 Proto-oncogene Promoter and Its Transcriptional Regulation. Sci Rep 2019; 9:3966. [PMID: 30850693 PMCID: PMC6408435 DOI: 10.1038/s41598-019-39941-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Accepted: 01/23/2019] [Indexed: 12/02/2022] Open
Abstract
G-quadruplexes in oncogene promoters provide putative targets for transcriptional regulation. The structure of a putative G-quadruplex sequence (S1: GGAGAAGGAGGAGGTGGAGGAGGAGGG) in potassium solution in the her2 promoter has been resolved mainly through nuclear magnetic resonance (NMR) spectroscopy. By application of various NMR spectra, we proved the formation of a four-layer G-quadruplex composing of two G-tetrads and two G/A-mixed planes with a four-residues loop (A3-G4-A5-A6). Further evidence from a luciferase reporter assay, Q-RT-PCR and Western blotting indicates that S1 G-quadruplex formation can repress her2 promoter activity, and a selected G-quadruplex ligand cβ can enhance the repression by down regulating her2 transcription and expression. These findings provide a G-quadruplex target and perspective implications in her2 transcriptional regulation.
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Affiliation(s)
- Xiaojie Cui
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Department of Chemical Biology, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China. .,College of Life and Environmental Sciences, Minzu University of China, Beijing, 100081, China.
| | - Han Chen
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Department of Chemical Biology, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China
| | - Qiang Zhang
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Department of Chemical Biology, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China
| | - Ming Xu
- Department of Cardiology, Institute of Vascular Medicine, Department of Cardiology, Peking University Third Hospital, Beijing, 100191, China
| | - Gu Yuan
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Department of Chemical Biology, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China
| | - Jiang Zhou
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Department of Chemical Biology, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China.
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14
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Sengar A, Vandana J, Chambers VS, Di Antonio M, Winnerdy F, Balasubramanian S, Phan AT. Structure of a (3+1) hybrid G-quadruplex in the PARP1 promoter. Nucleic Acids Res 2019; 47:1564-1572. [PMID: 30551210 PMCID: PMC6379715 DOI: 10.1093/nar/gky1179] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Revised: 11/02/2018] [Accepted: 12/12/2018] [Indexed: 01/08/2023] Open
Abstract
Poly (ADP-ribose) polymerase 1 (PARP1) has emerged as an attractive target for cancer therapy due to its key role in DNA repair processes. Inhibition of PARP1 in BRCA-mutated cancers has been observed to be clinically beneficial. Recent genome-mapping experiments have identified a non-canonical G-quadruplex-forming sequence containing bulges within the PARP1 promoter. Structural features, like bulges, provide opportunities for selective chemical targeting of the non-canonical G-quadruplex structure within the PARP1 promoter, which could serve as an alternative therapeutic approach for the regulation of PARP1 expression. Here we report the G-quadruplex structure formed by a 23-nucleotide G-rich sequence in the PARP1 promoter. Our study revealed a three-layered intramolecular (3+1) hybrid G-quadruplex scaffold, in which three strands are oriented in one direction and the fourth in the opposite direction. This structure exhibits unique structural features such as an adenine bulge and a G·G·T base triple capping structure formed between the central edgewise loop, propeller loop and 5' flanking terminal. Given the highly important role of PARP1 in DNA repair and cancer intervention, this structure presents an attractive opportunity to explore the therapeutic potential of PARP1 inhibition via G-quadruplex DNA targeting.
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Affiliation(s)
- Anjali Sengar
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - J Jeya Vandana
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Vicki S Chambers
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK
| | - Marco Di Antonio
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK
| | - Fernaldo Richtia Winnerdy
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Shankar Balasubramanian
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Cambridge CB2 0RE, UK
| | - Anh Tuân Phan
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
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15
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Jodoin R, Perreault JP. G-quadruplexes formation in the 5'UTRs of mRNAs associated with colorectal cancer pathways. PLoS One 2018; 13:e0208363. [PMID: 30507959 PMCID: PMC6277105 DOI: 10.1371/journal.pone.0208363] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Accepted: 11/15/2018] [Indexed: 11/24/2022] Open
Abstract
RNA G-quadruplexes (rG4) are stable non-canonical secondary structures composed of G-rich sequences. Many rG4 structures located in the 5'UTRs of mRNAs act as translation repressors due to their high stability which is thought to impede ribosomal scanning. That said, it is not known if these are mRNA-specific examples, or if they are indicative of a global expression regulation mechanism of the mRNAs involved in a common pathway based on structure folding recognition. Gene-ontology analysis of mRNAs bearing a predicted rG4 motif in their 5'UTRs revealed an enrichment for mRNAs associated with the colorectal cancer pathway. Bioinformatic tools for rG4 prediction, and experimental in vitro validations were used to confirm and compare the folding of the predicted rG4s of the mRNAs associated with dysregulated pathways in colorectal cancer. The rG4 folding was confirmed for the first time for 9 mRNAs. A repressive effect of 3 rG4 candidates on the expression of a reporter gene was also measured in colorectal cancer cell lines. This work highlights the fact that rG4 prediction is not yet accurate, and that experimental characterization is still essential in order to identify the precise rG4 folding sequences and the possible common features shared between the rG4 overrepresented in important biological pathways.
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Affiliation(s)
- Rachel Jodoin
- Département de Biochimie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Jean-Pierre Perreault
- Département de Biochimie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Sherbrooke, Québec, Canada
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16
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Varizhuk AM, Protopopova AD, Tsvetkov VB, Barinov NA, Podgorsky VV, Tankevich MV, Vlasenok MA, Severov VV, Smirnov IP, Dubrovin EV, Klinov DV, Pozmogova GE. Polymorphism of G4 associates: from stacks to wires via interlocks. Nucleic Acids Res 2018; 46:8978-8992. [PMID: 30107602 PMCID: PMC6158749 DOI: 10.1093/nar/gky729] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2018] [Revised: 07/30/2018] [Accepted: 07/31/2018] [Indexed: 01/16/2023] Open
Abstract
We examined the assembly of DNA G-quadruplexes (G4s) into higher-order structures using atomic force microscopy, optical and electrophoretic methods, NMR spectroscopy and molecular modeling. Our results suggest that parallel blunt-ended G4s with single-nucleotide or modified loops may form different types of multimers, ranging from stacks of intramolecular structures and/or interlocked dimers and trimers to wires. Decreasing the annealing rate and increasing salt or oligonucleotide concentrations shifted the equilibrium from intramolecular G4s to higher-order structures. Control antiparallel and hybrid G4s demonstrated no polymorphism or aggregation in our experiments. The modification that mimics abasic sites (1',2'-dideoxyribose residues) in loops enhanced the oligomerization/multimerization of both the 2-tetrad and 3-tetrad G4 motifs. Our results shed light on the rules that govern G4 rearrangements. Gaining control over G4 folding enables the harnessing of the full potential of such structures for guided assembly of supramolecular DNA structures for nanotechnology.
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Affiliation(s)
- Anna M Varizhuk
- Biophysics Department, Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow 119435, Russia
| | - Anna D Protopopova
- Biophysics Department, Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow 119435, Russia
| | - Vladimir B Tsvetkov
- Biophysics Department, Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow 119435, Russia
| | - Nikolay A Barinov
- Biophysics Department, Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow 119435, Russia
| | - Victor V Podgorsky
- Biophysics Department, Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow 119435, Russia
| | - Maria V Tankevich
- Biophysics Department, Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow 119435, Russia
| | - Maria A Vlasenok
- Biophysics Department, Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow 119435, Russia
| | - Vyacheslav V Severov
- Biophysics Department, Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow 119435, Russia
| | - Igor P Smirnov
- Biophysics Department, Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow 119435, Russia
| | - Evgeniy V Dubrovin
- Biophysics Department, Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow 119435, Russia
| | - Dmitry V Klinov
- Biophysics Department, Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow 119435, Russia
| | - Galina E Pozmogova
- Biophysics Department, Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow 119435, Russia
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17
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Garant JM, Perreault JP, Scott MS. Motif independent identification of potential RNA G-quadruplexes by G4RNA screener. Bioinformatics 2018; 33:3532-3537. [PMID: 29036425 PMCID: PMC5870565 DOI: 10.1093/bioinformatics/btx498] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Accepted: 08/01/2017] [Indexed: 11/29/2022] Open
Abstract
Motivation G-quadruplex structures in RNA molecules are known to have regulatory impacts in cells but are difficult to locate in the genome. The minimal requirements for G-quadruplex folding in RNA (G≥3N1-7 G≥3N1-7 G≥3N1-7 G≥3) is being challenged by observations made on specific examples in recent years. The definition of potential G-quadruplex sequences has major repercussions on the observation of the structure since it introduces a bias. The canonical motif only describes a sub-population of the reported G-quadruplexes. To address these issues, we propose an RNA G-quadruplex prediction strategy that does not rely on a motif definition. Results We trained an artificial neural network with sequences of experimentally validated G-quadruplexes from the G4RNA database encoded using an abstract definition of their sequence. This artificial neural network, G4NN, evaluates the similarity of a given sequence to known G-quadruplexes and reports it as a score. G4NN has a predictive power comparable to the reported G richness and G/C skewness evaluations that are the current state-of-the-art for the identification of potential RNA G-quadruplexes. We combined these approaches in the G4RNA screener, a program designed to manage and evaluate the sequences to identify potential G-quadruplexes. Availability and implementation G4RNA screener is available for download at http://gitlabscottgroup.med.usherbrooke.ca/J-Michel/g4rna_screener. Supplementary information Supplementary data are available at Bioinformatics online.
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Affiliation(s)
- Jean-Michel Garant
- RNA Group/Groupe ARN, Département de Biochimie, Faculté de Médecine des Sciences de la Santé, Pavillon de Recherche Appliquée au Cancer, Université de Sherbrooke, Sherbrooke, QC J1E 4K8, Canada
| | - Jean-Pierre Perreault
- RNA Group/Groupe ARN, Département de Biochimie, Faculté de Médecine des Sciences de la Santé, Pavillon de Recherche Appliquée au Cancer, Université de Sherbrooke, Sherbrooke, QC J1E 4K8, Canada
| | - Michelle S Scott
- RNA Group/Groupe ARN, Département de Biochimie, Faculté de Médecine des Sciences de la Santé, Pavillon de Recherche Appliquée au Cancer, Université de Sherbrooke, Sherbrooke, QC J1E 4K8, Canada
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18
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Garant JM, Perreault JP, Scott MS. G4RNA screener web server: User focused interface for RNA G-quadruplex prediction. Biochimie 2018; 151:115-118. [PMID: 29885355 DOI: 10.1016/j.biochi.2018.06.002] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Accepted: 06/04/2018] [Indexed: 12/11/2022]
Abstract
Though RNA G-quadruplexes became a focus of study over a decade ago, the main challenge associated with the identification of new potential G-quadruplexes remains a bottleneck step. It slows the study of these non-canonical structures in nucleic acids, and thus the understanding of their significance. The G4RNA screener is an accurate tool for the prediction of RNA G-quadruplexes but its deployment has brought to light an issue with its accessibility to G-quadruplex experts and biologists. G4RNA screener web server is a platform that provides a much needed interface to manage the input, parameters and result display of the main command-line ready tool. It is accessible at http://scottgroup.med.usherbrooke.ca/G4RNA_screener/.
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Affiliation(s)
- Jean-Michel Garant
- RNA Group/Groupe ARN, Département de Biochimie, Faculté de Médecine et des Sciences de la Santé, Pavillon de Recherche Appliquée au Cancer, Université de Sherbrooke, 3201 rue Jean-Mignault, Sherbrooke, Québec, J1E 4K8, Canada
| | - Jean-Pierre Perreault
- RNA Group/Groupe ARN, Département de Biochimie, Faculté de Médecine et des Sciences de la Santé, Pavillon de Recherche Appliquée au Cancer, Université de Sherbrooke, 3201 rue Jean-Mignault, Sherbrooke, Québec, J1E 4K8, Canada.
| | - Michelle S Scott
- RNA Group/Groupe ARN, Département de Biochimie, Faculté de Médecine et des Sciences de la Santé, Pavillon de Recherche Appliquée au Cancer, Université de Sherbrooke, 3201 rue Jean-Mignault, Sherbrooke, Québec, J1E 4K8, Canada.
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19
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Meier M, Moya-Torres A, Krahn NJ, McDougall MD, Orriss GL, McRae EK, Booy EP, McEleney K, Patel TR, McKenna SA, Stetefeld J. Structure and hydrodynamics of a DNA G-quadruplex with a cytosine bulge. Nucleic Acids Res 2018; 46:5319-5331. [PMID: 29718405 PMCID: PMC6007744 DOI: 10.1093/nar/gky307] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Revised: 04/05/2018] [Accepted: 04/12/2018] [Indexed: 12/27/2022] Open
Abstract
The identification of four-stranded G-quadruplexes (G4s) has highlighted the fact that DNA has additional spatial organisations at its disposal other than double-stranded helices. Recently, it became clear that the formation of G4s is not limited to the traditional G3+NL1G3+NL2G3+NL3G3+ sequence motif. Instead, the G3 triplets can be interrupted by deoxythymidylate (DNA) or uridylate (RNA) where the base forms a bulge that loops out from the G-quadruplex core. Here, we report the first high-resolution X-ray structure of a unique unimolecular DNA G4 with a cytosine bulge. The G4 forms a dimer that is stacked via its 5'-tetrads. Analytical ultracentrifugation, static light scattering and small angle X-ray scattering confirmed that the G4 adapts a predominantly dimeric structure in solution. We provide a comprehensive comparison of previously published G4 structures containing bulges and report a special γ torsion angle range preferentially populated by the G4 core guanylates adjacent to bulges. Since the penalty for introducing bulges appears to be negligible, it should be possible to functionalize G4s by introducing artificial or modified nucleotides at such positions. The presence of the bulge alters the surface of the DNA, providing an opportunity to develop drugs that can specifically target individual G4s.
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Affiliation(s)
- Markus Meier
- Department of Chemistry, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
| | - Aniel Moya-Torres
- Department of Chemistry, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
| | - Natalie J Krahn
- Department of Chemistry, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
| | - Matthew D McDougall
- Department of Chemistry, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
| | - George L Orriss
- Department of Chemistry, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
| | - Ewan K S McRae
- Department of Chemistry, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
| | - Evan P Booy
- Department of Chemistry, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
| | - Kevin McEleney
- Department of Chemistry, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
| | - Trushar R Patel
- Alberta RNA Research and Training Institute, Department of Chemistry and Biochemistry, University of Lethbridge, Lethbridge, Alberta T1K 3M4, Canada
- DiscoveryLab, Medical Sciences Building, University of Alberta, Edmonton, Alberta T6G 2H7, Canada
- Department of Microbiology, Immunology and Infectious Diseases, Cumming School of Medicine, University of Calgary, Calgary T2N 1N4, Alberta, Canada
| | - Sean A McKenna
- Department of Chemistry, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
- Department of Biochemistry and Medical Genetics, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
| | - Jörg Stetefeld
- Department of Chemistry, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
- Department of Biochemistry and Medical Genetics, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
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20
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Tan W, Yi L, Zhu Z, Zhang L, Zhou J, Yuan G. Hsa-miR-1587 G-quadruplex formation and dimerization induced by NH 4+, molecular crowding environment and jatrorrhizine derivatives. Talanta 2017; 179:337-343. [PMID: 29310241 DOI: 10.1016/j.talanta.2017.11.041] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2017] [Revised: 10/23/2017] [Accepted: 11/16/2017] [Indexed: 11/19/2022]
Abstract
A guanine-rich human mature microRNA, miR-1587, was discovered to form stable intramolecular G-quadruplexes in the presence of K+, Na+ and low concentration of NH4+ (25mM) by electrospray ionization mass spectrometry (ESI-MS) combined with circular dichroism (CD) spectroscopy. Furthermore, under high concentration of NH4+ (100mM) or molecular crowding environments, miR-1587 formed a dimeric G-quadruplex through 3'-to-3' stacking of two monomeric G-quadruplex subunits with one ammonium ion sandwiched between the interfaces. Specifically, two synthesized jatrorrhizine derivatives with terminal amine groups could also induce the dimerization of miR-1587 G-quadruplex and formed 1:1 and 2:1 complexes with the dimeric G-quadruplex. In contrast, jatrorrhizine could bind with the dimeric miR-1587 G-quadruplex, but could not induce dimerization of miR-1587 G-quadruplex. These results provide a new strategy to regulate the functions of miR-1587 through induction of G-quadruplex formation and dimerization.
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Affiliation(s)
- Wei Tan
- College of Chemistry and Molecular Engineering, Peking University, 202 Chengfu Road, Haidian District, Beijing 100871, China
| | - Long Yi
- Beijing Key Laboratory of Bioprocess, Beijing University of Chemical Engineering, Beijing 100029, China
| | - Zhentao Zhu
- Beijing Key Laboratory of Bioprocess, Beijing University of Chemical Engineering, Beijing 100029, China
| | - Lulu Zhang
- College of Chemistry and Molecular Engineering, Peking University, 202 Chengfu Road, Haidian District, Beijing 100871, China
| | - Jiang Zhou
- College of Chemistry and Molecular Engineering, Peking University, 202 Chengfu Road, Haidian District, Beijing 100871, China.
| | - Gu Yuan
- College of Chemistry and Molecular Engineering, Peking University, 202 Chengfu Road, Haidian District, Beijing 100871, China.
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21
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Jackowiak P, Hojka-Osinska A, Gasiorek K, Stelmaszczuk M, Gudanis D, Gdaniec Z, Figlerowicz M. Effects of G-quadruplex topology on translational inhibition by tRNA fragments in mammalian and plant systems in vitro. Int J Biochem Cell Biol 2017; 92:148-154. [PMID: 28989078 DOI: 10.1016/j.biocel.2017.10.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Revised: 09/05/2017] [Accepted: 10/04/2017] [Indexed: 02/07/2023]
Abstract
The folding of tRNA fragments (tRFs) into G-quadruplex structures and the implications of G-quadruplexes in translational inhibition have been studied mainly in mammalian systems. To increase our knowledge of these phenomena, we determined the influence of human and plant tRFs and model G-quadruplexes on translation in rabbit reticulocyte lysate and wheat germ extract. The efficiency of translational inhibition in the mammalian system was strongly associated with the type of G-quadruplex topology. In the plant system, the ability of a small RNA to adopt the G-quadruplex conformation was not sufficient to repress translation, indicating the importance of other structural determinants.
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Affiliation(s)
- Paulina Jackowiak
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland.
| | - Anna Hojka-Osinska
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland
| | - Katarzyna Gasiorek
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland
| | - Michal Stelmaszczuk
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland
| | - Dorota Gudanis
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland
| | - Zofia Gdaniec
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland
| | - Marek Figlerowicz
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland; Institute of Computing Science, Poznan University of Technology, Piotrowo 3A, 60-965 Poznan, Poland.
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22
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Agarwala P, Pal G, Pandey S, Maiti S. Mutagenesis Reveals an Unusual Combination of Guanines in RNA G-Quadruplex Formation. ACS OMEGA 2017; 2:4790-4799. [PMID: 31457759 PMCID: PMC6641730 DOI: 10.1021/acsomega.7b00377] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Accepted: 08/01/2017] [Indexed: 06/10/2023]
Abstract
The classic G-quadruplex motif consists of a continuous array of 3-4 guanine residues with an intermittent loop size of 1-7 nucleotides (G3-4N1-7G3-4N1-7G3-4N1-7G3-4). An RNA G-quadruplex is able to attain only one parallel G-quadruplex topology owing to steric constraints. Investigating the possibilities of the formation of RNA G-quadruplexes with a stretch of sequences deviating from this classic motif will add to the overall conformations of RNA G-quadruplexes, bestowing diversity to this structure. Here, we report unusual combinations of guanine residues involved in RNA G-quadruplex formation in the 5' untranslated region (UTR) of the von Willebrand factor (VWF) mRNA using the mutagenesis approach. Different permutations and combinations of guanine residues form G-quadruplexes. Upon investigation, G-quadruplexes in 5' UTR of VWF mRNA are shown to exhibit an inhibitory function.
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Affiliation(s)
- Prachi Agarwala
- Chemical
and Systems Biology, CSIR-Institute of Genomics
and Integrative Biology, Mall Road, Delhi 110007, India
- Academy
of Scientific and Innovative Research (AcSIR), Anusandhan Bhawan, 2 Rafi Marg, New Delhi 110001, India
| | - Gargi Pal
- Academy
of Scientific and Innovative Research (AcSIR), Anusandhan Bhawan, 2 Rafi Marg, New Delhi 110001, India
| | - Satyaprakash Pandey
- Chemical
and Systems Biology, CSIR-Institute of Genomics
and Integrative Biology, Mall Road, Delhi 110007, India
- Academy
of Scientific and Innovative Research (AcSIR), Anusandhan Bhawan, 2 Rafi Marg, New Delhi 110001, India
| | - Souvik Maiti
- Chemical
and Systems Biology, CSIR-Institute of Genomics
and Integrative Biology, Mall Road, Delhi 110007, India
- Academy
of Scientific and Innovative Research (AcSIR), Anusandhan Bhawan, 2 Rafi Marg, New Delhi 110001, India
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23
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Antiparallel RNA G-quadruplex Formed by Human Telomere RNA Containing 8-Bromoguanosine. Sci Rep 2017; 7:6695. [PMID: 28751647 PMCID: PMC5532209 DOI: 10.1038/s41598-017-07050-w] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Accepted: 06/21/2017] [Indexed: 11/09/2022] Open
Abstract
In this study, by combining nuclear magnetic resonance (NMR), circular dichroism (CD), liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS), and gel electrophoresis, we report an unusual topological structure of the RNA G-quadruplex motif formed by human telomere RNA r(UAGGGU) containing 8-bromoguanosine. Results showed that the RNA sequence formed an antiparallel tetramolecular G-quadruplex, in which each pair of diagonal strands run in opposite directions. Furthermore, guanosines were observed both in syn- and anti-conformations. In addition, two of these G-quadruplex subunits were found to be stacking on top of each other, forming a dimeric RNA G-quadruplex. Our findings provide a new insight into the behavior of RNA G-quadruplex structures.
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24
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Dolinnaya NG, Ogloblina AM, Yakubovskaya MG. Structure, Properties, and Biological Relevance of the DNA and RNA G-Quadruplexes: Overview 50 Years after Their Discovery. BIOCHEMISTRY (MOSCOW) 2017; 81:1602-1649. [PMID: 28260487 PMCID: PMC7087716 DOI: 10.1134/s0006297916130034] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
G-quadruplexes (G4s), which are known to have important roles in regulation of key biological processes in both normal and pathological cells, are the most actively studied non-canonical structures of nucleic acids. In this review, we summarize the results of studies published in recent years that change significantly scientific views on various aspects of our understanding of quadruplexes. Modern notions on the polymorphism of DNA quadruplexes, on factors affecting thermodynamics and kinetics of G4 folding–unfolding, on structural organization of multiquadruplex systems, and on conformational features of RNA G4s and hybrid DNA–RNA G4s are discussed. Here we report the data on location of G4 sequence motifs in the genomes of eukaryotes, bacteria, and viruses, characterize G4-specific small-molecule ligands and proteins, as well as the mechanisms of their interactions with quadruplexes. New information on the structure and stability of G4s in telomeric DNA and oncogene promoters is discussed as well as proof being provided on the occurrence of G-quadruplexes in cells. Prominence is given to novel experimental techniques (single molecule manipulations, optical and magnetic tweezers, original chemical approaches, G4 detection in situ, in-cell NMR spectroscopy) that facilitate breakthroughs in the investigation of the structure and functions of G-quadruplexes.
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Affiliation(s)
- N G Dolinnaya
- Lomonosov Moscow State University, Department of Chemistry, Moscow, 119991, Russia.
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25
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Rouleau S, Jodoin R, Garant JM, Perreault JP. RNA G-Quadruplexes as Key Motifs of the Transcriptome. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2017; 170:1-20. [PMID: 28382477 DOI: 10.1007/10_2017_8] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
G-Quadruplexes are non-canonical secondary structures that can be adopted under physiological conditions by guanine-rich DNA and RNA molecules. They have been reported to occur, and to perform multiple biological functions, in the genomes and transcriptomes of many species, including humans. This chapter focuses specifically on RNA G-quadruplexes and reviews the most recent discoveries in the field, as well as addresses the upcoming challenges researchers studying these structures face.
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Affiliation(s)
- Samuel Rouleau
- RNA Group/Groupe ARN, Département de Biochimie, Faculté de médecine des sciences de la santé, Pavillon de Recherche Appliquée au Cancer, Université de Sherbrooke, 3201 rue Jean-Mignault, Sherbrooke, QC, Canada, J1E 4K8
| | - Rachel Jodoin
- RNA Group/Groupe ARN, Département de Biochimie, Faculté de médecine des sciences de la santé, Pavillon de Recherche Appliquée au Cancer, Université de Sherbrooke, 3201 rue Jean-Mignault, Sherbrooke, QC, Canada, J1E 4K8
| | - Jean-Michel Garant
- RNA Group/Groupe ARN, Département de Biochimie, Faculté de médecine des sciences de la santé, Pavillon de Recherche Appliquée au Cancer, Université de Sherbrooke, 3201 rue Jean-Mignault, Sherbrooke, QC, Canada, J1E 4K8
| | - Jean-Pierre Perreault
- RNA Group/Groupe ARN, Département de Biochimie, Faculté de médecine des sciences de la santé, Pavillon de Recherche Appliquée au Cancer, Université de Sherbrooke, 3201 rue Jean-Mignault, Sherbrooke, QC, Canada, J1E 4K8.
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26
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Song J, Perreault JP, Topisirovic I, Richard S. RNA G-quadruplexes and their potential regulatory roles in translation. ACTA ACUST UNITED AC 2016; 4:e1244031. [PMID: 28090421 PMCID: PMC5173311 DOI: 10.1080/21690731.2016.1244031] [Citation(s) in RCA: 96] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Revised: 09/26/2016] [Accepted: 09/28/2016] [Indexed: 12/11/2022]
Abstract
DNA guanine (G)-rich 4-stranded helical nucleic acid structures called G-quadruplexes (G4), have been extensively studied during the last decades. However, emerging evidence reveals that 5′- and 3′-untranslated regions (5′- and 3′-UTRs) as well as open reading frames (ORFs) contain putative RNA G-quadruplexes. These stable secondary structures play key roles in telomere homeostasis and RNA metabolism including pre-mRNA splicing, polyadenylation, mRNA targeting and translation. Interestingly, multiple RNA binding proteins such as nucleolin, FMRP, DHX36, and Aven were identified to bind RNA G-quadruplexes. Moreover, accumulating reports suggest that RNA G-quadruplexes regulate translation in cap-dependent and -independent manner. Herein, we discuss potential roles of RNA G-quadruplexes and associated trans-acting factors in the regulation of mRNA translation.
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Affiliation(s)
- Jingwen Song
- Terry Fox Molecular Oncology Group and Segal Cancer Center, McGill University, Montréal, Québec, Canada; Bloomfield Center for Research on Aging, Lady Davis Institute for Medical Research, McGill University, Montréal, Québec, Canada; Department of Oncology, McGill University, Montréal, Québec, Canada; Department of Medicine, McGill University, Montréal, Québec, Canada
| | | | - Ivan Topisirovic
- Terry Fox Molecular Oncology Group and Segal Cancer Center, McGill University, Montréal, Québec, Canada; Department of Oncology, McGill University, Montréal, Québec, Canada; Department of Biochemistry, McGill University, Montréal, Québec, Canada
| | - Stéphane Richard
- Terry Fox Molecular Oncology Group and Segal Cancer Center, McGill University, Montréal, Québec, Canada; Bloomfield Center for Research on Aging, Lady Davis Institute for Medical Research, McGill University, Montréal, Québec, Canada; Department of Oncology, McGill University, Montréal, Québec, Canada; Department of Medicine, McGill University, Montréal, Québec, Canada
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27
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Kwok CK, Marsico G, Sahakyan AB, Chambers VS, Balasubramanian S. rG4-seq reveals widespread formation of G-quadruplex structures in the human transcriptome. Nat Methods 2016; 13:841-4. [PMID: 27571552 DOI: 10.1038/nmeth.3965] [Citation(s) in RCA: 260] [Impact Index Per Article: 32.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Accepted: 07/21/2016] [Indexed: 12/11/2022]
Abstract
We introduce RNA G-quadruplex sequencing (rG4-seq), a transcriptome-wide RNA G-quadruplex (rG4) profiling method that couples rG4-mediated reverse transcriptase stalling with next-generation sequencing. Using rG4-seq on polyadenylated-enriched HeLa RNA, we generated a global in vitro map of thousands of canonical and noncanonical rG4 structures. We characterize rG4 formation relative to cytosine content and alternative RNA structure stability, uncover rG4-dependent differences in RNA folding and show evolutionarily conserved enrichment in transcripts mediating RNA processing and stability.
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Affiliation(s)
- Chun Kit Kwok
- Department of Chemistry, University of Cambridge, Cambridge, UK.,Cancer Research UK, Cambridge Institute, Cambridge, UK
| | - Giovanni Marsico
- Department of Chemistry, University of Cambridge, Cambridge, UK.,Cancer Research UK, Cambridge Institute, Cambridge, UK
| | - Aleksandr B Sahakyan
- Department of Chemistry, University of Cambridge, Cambridge, UK.,Cancer Research UK, Cambridge Institute, Cambridge, UK
| | - Vicki S Chambers
- Department of Chemistry, University of Cambridge, Cambridge, UK.,Cancer Research UK, Cambridge Institute, Cambridge, UK
| | - Shankar Balasubramanian
- Department of Chemistry, University of Cambridge, Cambridge, UK.,Cancer Research UK, Cambridge Institute, Cambridge, UK
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28
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Largy E, Mergny JL, Gabelica V. Role of Alkali Metal Ions in G-Quadruplex Nucleic Acid Structure and Stability. Met Ions Life Sci 2016; 16:203-58. [PMID: 26860303 DOI: 10.1007/978-3-319-21756-7_7] [Citation(s) in RCA: 105] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
G-quadruplexes are guanine-rich nucleic acids that fold by forming successive quartets of guanines (the G-tetrads), stabilized by intra-quartet hydrogen bonds, inter-quartet stacking, and cation coordination. This specific although highly polymorphic type of secondary structure deviates significantly from the classical B-DNA duplex. G-quadruplexes are detectable in human cells and are strongly suspected to be involved in a number of biological processes at the DNA and RNA levels. The vast structural polymorphism exhibited by G-quadruplexes, together with their putative biological relevance, makes them attractive therapeutic targets compared to canonical duplex DNA. This chapter focuses on the essential and specific coordination of alkali metal cations by G-quadruplex nucleic acids, and most notably on studies highlighting cation-dependent dissimilarities in their stability, structure, formation, and interconversion. Section 1 surveys G-quadruplex structures and their interactions with alkali metal ions while Section 2 presents analytical methods used to study G-quadruplexes. The influence of alkali cations on the stability, structure, and kinetics of formation of G-quadruplex structures of quadruplexes will be discussed in Sections 3 and 4. Section 5 focuses on the cation-induced interconversion of G-quadruplex structures. In Sections 3 to 5, we will particularly emphasize the comparisons between cations, most often K(+) and Na(+) because of their prevalence in the literature and in cells.
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Affiliation(s)
- Eric Largy
- ARNA Laboratory, Université Bordeaux, IECB, 2, rue Robert Escarpit, F-33600, Pessac, France.,ARNA Laboratory, INSERM, U869, F-33000, Bordeaux, France
| | - Jean-Louis Mergny
- ARNA Laboratory, Université Bordeaux, IECB, 2, rue Robert Escarpit, F-33600, Pessac, France. .,ARNA Laboratory, INSERM, U869, F-33000, Bordeaux, France.
| | - Valérie Gabelica
- ARNA Laboratory, Université Bordeaux, IECB, 2, rue Robert Escarpit, F-33600, Pessac, France. .,ARNA Laboratory, INSERM, U869, F-33000, Bordeaux, France.
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29
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Physical Connectivity Mapping by Circular Permutation of Human Telomerase RNA Reveals New Regions Critical for Activity and Processivity. Mol Cell Biol 2015; 36:251-61. [PMID: 26503788 DOI: 10.1128/mcb.00794-15] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Accepted: 10/22/2015] [Indexed: 01/04/2023] Open
Abstract
Telomerase is a specialized ribonucleoprotein complex that extends the 3' ends of chromosomes to counteract telomere shortening. However, increased telomerase activity is associated with ∼90% of human cancers. The telomerase enzyme minimally requires an RNA (hTR) and a specialized reverse transcriptase protein (TERT) for activity in vitro. Understanding the structure-function relationships within hTR has important implications for human disease. For the first time, we have tested the physical-connectivity requirements in the 451-nucleotide hTR RNA using circular permutations, which reposition the 5' and 3' ends. Our extensive in vitro analysis identified three classes of hTR circular permutants with altered function. First, circularly permuting 3' of the template causes specific defects in repeat-addition processivity, revealing that the template recognition element found in ciliates is conserved in human telomerase RNA. Second, seven circular permutations residing within the catalytically important core and CR4/5 domains completely abolish telomerase activity, unveiling mechanistically critical portions of these domains. Third, several circular permutations between the core and CR4/5 significantly increase telomerase activity. Our extensive circular permutation results provide insights into the architecture and coordination of human telomerase RNA and highlight where the RNA could be targeted for the development of antiaging and anticancer therapeutics.
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30
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Insights into G-quadruplex specific recognition by the DEAH-box helicase RHAU: Solution structure of a peptide-quadruplex complex. Proc Natl Acad Sci U S A 2015. [PMID: 26195789 DOI: 10.1073/pnas.1422605112] [Citation(s) in RCA: 106] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Four-stranded nucleic acid structures called G-quadruplexes have been associated with important cellular processes, which should require G-quadruplex-protein interaction. However, the structural basis for specific G-quadruplex recognition by proteins has not been understood. The DEAH (Asp-Glu-Ala-His) box RNA helicase associated with AU-rich element (RHAU) (also named DHX36 or G4R1) specifically binds to and resolves parallel-stranded G-quadruplexes. Here we identified an 18-amino acid G-quadruplex-binding domain of RHAU and determined the structure of this peptide bound to a parallel DNA G-quadruplex. Our structure explains how RHAU specifically recognizes parallel G-quadruplexes. The peptide covers a terminal guanine base tetrad (G-tetrad), and clamps the G-quadruplex using three-anchor-point electrostatic interactions between three positively charged amino acids and negatively charged phosphate groups. This binding mode is strikingly similar to that of most ligands selected for specific G-quadruplex targeting. Binding to an exposed G-tetrad represents a simple and efficient way to specifically target G-quadruplex structures.
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31
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Kwok CK, Balasubramanian S. Targeted Detection of G-Quadruplexes in Cellular RNAs. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201500891] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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32
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Kwok CK, Balasubramanian S. Targeted Detection of G-Quadruplexes in Cellular RNAs. Angew Chem Int Ed Engl 2015; 54:6751-4. [PMID: 25907625 PMCID: PMC4510783 DOI: 10.1002/anie.201500891] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Revised: 03/25/2015] [Indexed: 02/03/2023]
Abstract
The G-quadruplex (G4) is a non-canonical nucleic acid structure which regulates important cellular processes. RNA G4s have recently been shown to exist in human cells and be biologically significant. Described herein is a new approach to detect and map RNA G4s in cellular transcripts. This method exploits the specific control of RNA G4-cation and RNA G4-ligand interactions during reverse transcription, by using a selective reverse transcriptase to monitor RNA G4-mediated reverse transcriptase stalling (RTS) events. Importantly, a ligation-amplification strategy is coupled with RTS, and enables detection and mapping of G4s in important, low-abundance cellular RNAs. Strong evidence is provided for G4 formation in full-length cellular human telomerase RNA, offering important insights into its cellular function.
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Affiliation(s)
- Chun Kit Kwok
- The University of Cambridge, Department of Chemistry, Lensfield Road, Cambridge, CB2 1EW (UK)
| | - Shankar Balasubramanian
- The University of Cambridge, Department of Chemistry, Lensfield Road, Cambridge, CB2 1EW (UK).
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33
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Wei D, Husby J, Neidle S. Flexibility and structural conservation in a c-KIT G-quadruplex. Nucleic Acids Res 2014; 43:629-44. [PMID: 25452341 PMCID: PMC4288176 DOI: 10.1093/nar/gku1282] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
A quadruplex sequence from the promoter region of the c-KIT gene forms a stable quadruplex, as characterized by crystallographic and NMR methods. Two new crystal structures are reported here, together with molecular dynamics simulation studies on these quadruplex crystal structures and an NMR structure. The new crystal structures, each in a distinct space group and lattice packing arrangement, together with the existing structures, demonstrate that the c-KIT quadruplex fold does not change with differing environments, suggesting that quadruplex topological dynamism is not a general phenomenon. The single and dinucleotide loops in these structures show a high degree of conformational flexibility within the three crystal forms and the NMR ensemble, with no evidence of clustering to particular conformers. This is in accord with the findings of high loop flexibility from the molecular dynamics studies. It is suggested that intramolecular quadruplexes can be grouped into two broad classes (i) those with at least one single-nucleotide loop, often showing singular topologies even though loops are highly flexible, and (ii) with all loops comprising at least two nucleotides, leading to topological dynamism. The loops can have more stable and less dynamic base-stacked secondary structures.
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Affiliation(s)
- Dengguo Wei
- UCL School of Pharmacy, University College London, London WC1N 1AX, UK
| | - Jarmila Husby
- UCL School of Pharmacy, University College London, London WC1N 1AX, UK
| | - Stephen Neidle
- UCL School of Pharmacy, University College London, London WC1N 1AX, UK
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