1
|
Guneri D, Alexandrou E, El Omari K, Dvořáková Z, Chikhale RV, Pike DTS, Waudby CA, Morris CJ, Haider S, Parkinson GN, Waller ZAE. Structural insights into i-motif DNA structures in sequences from the insulin-linked polymorphic region. Nat Commun 2024; 15:7119. [PMID: 39164244 PMCID: PMC11336075 DOI: 10.1038/s41467-024-50553-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Accepted: 07/12/2024] [Indexed: 08/22/2024] Open
Abstract
The insulin-linked polymorphic region is a variable number of tandem repeats region of DNA in the promoter of the insulin gene that regulates transcription of insulin. This region is known to form the alternative DNA structures, i-motifs and G-quadruplexes. Individuals have different sequence variants of tandem repeats and although previous work investigated the effects of some variants on G-quadruplex formation, there is not a clear picture of the relationship between the sequence diversity, the DNA structures formed, and the functional effects on insulin gene expression. Here we show that different sequence variants of the insulin linked polymorphic region form different DNA structures in vitro. Additionally, reporter genes in cellulo indicate that insulin expression may change depending on which DNA structures form. We report the crystal structure and dynamics of an intramolecular i-motif, which reveal sequences within the loop regions forming additional stabilising interactions that are critical to formation of stable i-motif structures. The outcomes of this work reveal the detail in formation of stable i-motif DNA structures, with potential for rational based drug design for compounds to target i-motif DNA.
Collapse
Affiliation(s)
- Dilek Guneri
- School of Pharmacy, University College London, 29-39 Brunswick Square, London, WC1N 1AX, UK
| | - Effrosyni Alexandrou
- School of Pharmacy, University College London, 29-39 Brunswick Square, London, WC1N 1AX, UK
| | - Kamel El Omari
- Diamond Light Source, Harwell Science and Innovation Campus, Chilton, Didcot, OX11 0DE, UK
| | - Zuzana Dvořáková
- Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, 612 00, Brno, Czech Republic
| | - Rupesh V Chikhale
- School of Pharmacy, University College London, 29-39 Brunswick Square, London, WC1N 1AX, UK
| | - Daniel T S Pike
- School of Pharmacy, University College London, 29-39 Brunswick Square, London, WC1N 1AX, UK
| | - Christopher A Waudby
- School of Pharmacy, University College London, 29-39 Brunswick Square, London, WC1N 1AX, UK
| | - Christopher J Morris
- School of Pharmacy, University College London, 29-39 Brunswick Square, London, WC1N 1AX, UK.
| | - Shozeb Haider
- School of Pharmacy, University College London, 29-39 Brunswick Square, London, WC1N 1AX, UK.
- UCL Centre for Advanced Research Computing, University College London, Gower Street, London, WC1E 6BT, UK.
| | - Gary N Parkinson
- School of Pharmacy, University College London, 29-39 Brunswick Square, London, WC1N 1AX, UK.
| | - Zoë A E Waller
- School of Pharmacy, University College London, 29-39 Brunswick Square, London, WC1N 1AX, UK.
| |
Collapse
|
2
|
Parise A, Cresca S, Magistrato A. Molecular dynamics simulations for the structure-based drug design: targeting small-GTPases proteins. Expert Opin Drug Discov 2024:1-21. [PMID: 39105536 DOI: 10.1080/17460441.2024.2387856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2024] [Accepted: 07/30/2024] [Indexed: 08/07/2024]
Abstract
INTRODUCTION Molecular Dynamics (MD) simulations can support mechanism-based drug design. Indeed, MD simulations by capturing biomolecule motions at finite temperatures can reveal hidden binding sites, accurately predict drug-binding poses, and estimate the thermodynamics and kinetics, crucial information for drug discovery campaigns. Small-Guanosine Triphosphate Phosphohydrolases (GTPases) regulate a cascade of signaling events, that affect most cellular processes. Their deregulation is linked to several diseases, making them appealing drug targets. The broad roles of small-GTPases in cellular processes and the recent approval of a covalent KRas inhibitor as an anticancer agent renewed the interest in targeting small-GTPase with small molecules. AREA COVERED This review emphasizes the role of MD simulations in elucidating small-GTPase mechanisms, assessing the impact of cancer-related variants, and discovering novel inhibitors. EXPERT OPINION The application of MD simulations to small-GTPases exemplifies the role of MD simulations in the structure-based drug design process for challenging biomolecular targets. Furthermore, AI and machine learning-enhanced MD simulations, coupled with the upcoming power of quantum computing, are promising instruments to target elusive small-GTPases mutations and splice variants. This powerful synergy will aid in developing innovative therapeutic strategies associated to small-GTPases deregulation, which could potentially be used for personalized therapies and in a tissue-agnostic manner to treat tumors with mutations in small-GTPases.
Collapse
Affiliation(s)
- Angela Parise
- Consiglio Nazionale delle Ricerche (CNR) - Istituto Officina dei Materiali (IOM), c/o International School for Advanced Studies (SISSA), Trieste, Italy
| | - Sofia Cresca
- Consiglio Nazionale delle Ricerche (CNR) - Istituto Officina dei Materiali (IOM), c/o International School for Advanced Studies (SISSA), Trieste, Italy
| | - Alessandra Magistrato
- Consiglio Nazionale delle Ricerche (CNR) - Istituto Officina dei Materiali (IOM), c/o International School for Advanced Studies (SISSA), Trieste, Italy
| |
Collapse
|
3
|
Wu Y, Wang GA, Yang Q, Li F. Native Characterization of Noncanonical Nucleic Acid Thermodynamics via Programmable Dynamic DNA Chemistry. J Am Chem Soc 2024; 146:18041-18049. [PMID: 38899479 DOI: 10.1021/jacs.4c04721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/21/2024]
Abstract
Folding thermodynamics, quantitatively described using parameters such as ΔGfold°, ΔHfold°, and ΔSfold°, is essential for characterizing the stability and functionality of noncanonical nucleic acid structures but remains difficult to measure at the molecular level. Leveraging the programmability of dynamic deoxyribonucleic acid (DNA) chemistry, we introduce a DNA-based molecular tool capable of performing a free energy shift assay (FESA) that directly characterizes the thermodynamics of noncanonical DNA structures in their native environments. FESA operates by the rational design of a reference DNA probe that is energetically equivalent to a target noncanonical nucleic acid structure in a series of toehold-exchange reactions, yet is structurally incapable of folding. As a result, a free energy shift (ΔΔGrxn°) is observed when plotting the reaction yield against the free energy of each toehold-exchange. We mathematically demonstrated that ΔGfold°, ΔHfold°, and ΔSfold° of the analyte can be calculated based on ΔΔGrxn°. After validating FESA using six DNA hairpins by comparing the measured ΔGfold°, ΔHfold°, and ΔSfold° values against predictions made by NUPACK software, we adapted FESA to characterize noncanonical nucleic acid structures, encompassing DNA triplexes, G-quadruplexes, and aptamers. This adaptation enabled the successful characterization of the folding thermodynamics for these complex structures under various experimental conditions. The successful development of FESA marks a paradigm shift and a technical advancement in characterizing the thermodynamics of noncanonical DNA structures through molecular tools. It also opens new avenues for probing fundamental chemical and biophysical questions through the lens of molecular engineering and dynamic DNA chemistry.
Collapse
Affiliation(s)
- Yuqin Wu
- Key Laboratory of Green Chemistry and Technology of Ministry of Education, College of Chemistry, Sichuan University, Chengdu, Sichuan 610064, China
| | - Guan Alex Wang
- Key Laboratory of Green Chemistry and Technology of Ministry of Education, College of Chemistry, Sichuan University, Chengdu, Sichuan 610064, China
| | - Qianfan Yang
- Key Laboratory of Green Chemistry and Technology of Ministry of Education, College of Chemistry, Sichuan University, Chengdu, Sichuan 610064, China
| | - Feng Li
- Key Laboratory of Green Chemistry and Technology of Ministry of Education, College of Chemistry, Sichuan University, Chengdu, Sichuan 610064, China
- Department of Chemistry, Centre for Biotechnology, Brock University, St. Catharines, Ontario L2S 3A1, Canada
| |
Collapse
|
4
|
Yatsunyk LA, Neidle S. On Water Arrangements in Right- and Left-Handed DNA Structures. Molecules 2024; 29:505. [PMID: 38276583 PMCID: PMC10820154 DOI: 10.3390/molecules29020505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Revised: 01/07/2024] [Accepted: 01/15/2024] [Indexed: 01/27/2024] Open
Abstract
DNA requires hydration to maintain its structural integrity. Crystallographic analyses have enabled patterns of water arrangements to be visualized. We survey these water motifs in this review, focusing on left- and right-handed duplex and quadruplex DNAs, together with the i-motif. Common patterns of linear spines of water organization in grooves have been identified and are widely prevalent in right-handed duplexes and quadruplexes. By contrast, a left-handed quadruplex has a distinctive wheel of hydration populating the almost completely circular single groove in this structure.
Collapse
Affiliation(s)
- Liliya A. Yatsunyk
- Department of Chemistry and Biochemistry, Swarthmore College, Swarthmore, PA 19081, USA;
| | - Stephen Neidle
- UCL School of Pharmacy, University College London, London WC1N 1AX, UK
| |
Collapse
|
5
|
Ghezzo M, Trajkovski M, Plavec J, Sissi C. A Screening Protocol for Exploring Loop Length Requirements for the Formation of a Three Cytosine-Cytosine + Base-Paired i-Motif. Angew Chem Int Ed Engl 2023; 62:e202309327. [PMID: 37611164 DOI: 10.1002/anie.202309327] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 08/21/2023] [Accepted: 08/23/2023] [Indexed: 08/25/2023]
Abstract
DNA sequences containing at least four runs of repetitive cytosines can fold into tetra-helical structures called i-Motifs (iMs). The interest in these DNA secondary structures is increasing due to their therapeutical and technological applications. Still, limited knowledge of their folding requirements is currently available. We developed a novel step-by-step pipeline for the systematic screening of putative iM-forming model sequences. Focusing on structures comprising only three cytosine-cytosine+ base pairs, we investigated what the minimal lengths of the loops required for formation of an intra-molecular iM are. Our data indicate that two and three nucleotides are required to connect the strands through the minor and majorgrooves of the iM, respectively. Additionally, they highlight an asymmetric behavior according to the distribution of the cytosines. Specifically, no sequence containing a single cytosine in the first and third run was able to fold into intra-molecular iMs with the same stability of those formed when the first and the third run comprise two cytosines. This knowledge represents a step forward toward the development of prediction tools for the proper identification of biologically functional iMs, as well as for the rational design of these secondary structures as technological devices.
Collapse
Affiliation(s)
- Michele Ghezzo
- Department of Pharmaceutical and Pharmacological Science, University of Padua, Via Marzolo 5, 35131, Padua, Italy
| | - Marko Trajkovski
- Slovenian NMR Centre, National Institute of Chemistry, Hajdrihova 19, 1000, Ljubljana, Slovenia
| | - Janez Plavec
- Slovenian NMR Centre, National Institute of Chemistry, Hajdrihova 19, 1000, Ljubljana, Slovenia
| | - Claudia Sissi
- Department of Pharmaceutical and Pharmacological Science, University of Padua, Via Marzolo 5, 35131, Padua, Italy
| |
Collapse
|