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Loh YY, Anantharajan J, Huang Q, Xu W, Fulwood J, Ng HQ, Ng EY, Gea CY, Choong ML, Tan QW, Koh X, Lim WH, Nacro K, Cherian J, Baburajendran N, Ke Z, Kang C. Identification of small-molecule binding sites of a ubiquitin-conjugating enzyme-UBE2T through fragment-based screening. Protein Sci 2024; 33:e4904. [PMID: 38358126 PMCID: PMC10868430 DOI: 10.1002/pro.4904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 01/03/2024] [Accepted: 01/04/2024] [Indexed: 02/16/2024]
Abstract
UBE2T is an attractive target for drug development due to its linkage with several types of cancers. However, the druggability of ubiquitin-conjugating E2 (UBE2T) is low because of the lack of a deep and hydrophobic pocket capable of forming strong binding interactions with drug-like small molecules. Here, we performed fragment screening using 19 F-nuclear magnetic resonance (NMR) and validated the hits with 1 H-15 N-heteronuclear single quantum coherence (HSQC) experiment and X-ray crystallographic studies. The cocrystal structures obtained revealed the binding modes of the hit fragments and allowed for the characterization of the fragment-binding sites. Further screening of structural analogues resulted in the identification of a compound series with inhibitory effect on UBE2T activity. Our current study has identified two new binding pockets in UBE2T, which will be useful for the development of small molecules to regulate the function of this protein. In addition, the compounds identified in this study can serve as chemical starting points for the development of UBE2T modulators.
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Affiliation(s)
- Yong Yao Loh
- Experimental Drug Development Centre (EDDC)Agency for Science, Technology and Research (A*STAR)SingaporeSingapore
| | - Jothi Anantharajan
- Experimental Drug Development Centre (EDDC)Agency for Science, Technology and Research (A*STAR)SingaporeSingapore
| | - Qiwei Huang
- Experimental Drug Development Centre (EDDC)Agency for Science, Technology and Research (A*STAR)SingaporeSingapore
| | - Weijun Xu
- Experimental Drug Development Centre (EDDC)Agency for Science, Technology and Research (A*STAR)SingaporeSingapore
| | - Justina Fulwood
- Experimental Drug Development Centre (EDDC)Agency for Science, Technology and Research (A*STAR)SingaporeSingapore
| | - Hui Qi Ng
- Experimental Drug Development Centre (EDDC)Agency for Science, Technology and Research (A*STAR)SingaporeSingapore
| | - Elizabeth Yihui Ng
- Experimental Drug Development Centre (EDDC)Agency for Science, Technology and Research (A*STAR)SingaporeSingapore
| | - Chong Yu Gea
- Experimental Drug Development Centre (EDDC)Agency for Science, Technology and Research (A*STAR)SingaporeSingapore
| | - Meng Ling Choong
- Experimental Drug Development Centre (EDDC)Agency for Science, Technology and Research (A*STAR)SingaporeSingapore
| | - Qian Wen Tan
- Experimental Drug Development Centre (EDDC)Agency for Science, Technology and Research (A*STAR)SingaporeSingapore
| | - Xiaoying Koh
- Experimental Drug Development Centre (EDDC)Agency for Science, Technology and Research (A*STAR)SingaporeSingapore
| | - Wan Hsin Lim
- Experimental Drug Development Centre (EDDC)Agency for Science, Technology and Research (A*STAR)SingaporeSingapore
| | - Kassoum Nacro
- Experimental Drug Development Centre (EDDC)Agency for Science, Technology and Research (A*STAR)SingaporeSingapore
| | - Joseph Cherian
- Experimental Drug Development Centre (EDDC)Agency for Science, Technology and Research (A*STAR)SingaporeSingapore
| | - Nithya Baburajendran
- Experimental Drug Development Centre (EDDC)Agency for Science, Technology and Research (A*STAR)SingaporeSingapore
| | - Zhiyuan Ke
- Experimental Drug Development Centre (EDDC)Agency for Science, Technology and Research (A*STAR)SingaporeSingapore
| | - CongBao Kang
- Experimental Drug Development Centre (EDDC)Agency for Science, Technology and Research (A*STAR)SingaporeSingapore
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2
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Anantharajan J, Tan QW, Fulwood J, Sifang W, Huang Q, Ng HQ, Koh X, Xu W, Cherian J, Baburajendran N, Kang C, Ke Z. Identification and characterization of inhibitors covalently modifying catalytic cysteine of UBE2T and blocking ubiquitin transfer. Biochem Biophys Res Commun 2023; 689:149238. [PMID: 37979329 DOI: 10.1016/j.bbrc.2023.149238] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2023] [Revised: 11/08/2023] [Accepted: 11/08/2023] [Indexed: 11/20/2023]
Abstract
UBE2T is an E2 ubiquitin ligase critical for ubiquitination of substrate and plays important roles in many diseases. Despite the important function, UBE2T is considered as an undruggable target due to lack of a pocket for binding to small molecules with satisfied properties for clinical applications. To develop potent and specific UBE2T inhibitors, we adopted a high-throughput screening assay and two compounds-ETC-6152 and ETC-9004 containing a sulfone tetrazole scaffold were identified. Solution NMR study demonstrated the direct interactions between UBE2T and compounds in solution. Further co-crystal structures reveal the binding modes of these compounds. Both compound hydrolysation and formation of a hydrogen bond with the thiol group of the catalytic cysteine were observed. The formation of covalent complex was confirmed with mass spectrometry. As these two compounds inhibit ubiquitin transfer, our study provides a strategy to develop potent inhibitors of UBE2T.
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Affiliation(s)
- Jothi Anantharajan
- Experimental Drug Development Centre (EDDC), Agency for Science, Technology and Research (A*STAR), 10 Biopolis Road, #5-01, 138670, Singapore
| | - Qian Wen Tan
- Experimental Drug Development Centre (EDDC), Agency for Science, Technology and Research (A*STAR), 10 Biopolis Road, #5-01, 138670, Singapore
| | - Justina Fulwood
- Experimental Drug Development Centre (EDDC), Agency for Science, Technology and Research (A*STAR), 10 Biopolis Road, #5-01, 138670, Singapore
| | - Wang Sifang
- Experimental Drug Development Centre (EDDC), Agency for Science, Technology and Research (A*STAR), 10 Biopolis Road, #5-01, 138670, Singapore
| | - Qiwei Huang
- Experimental Drug Development Centre (EDDC), Agency for Science, Technology and Research (A*STAR), 10 Biopolis Road, #5-01, 138670, Singapore
| | - Hui Qi Ng
- Experimental Drug Development Centre (EDDC), Agency for Science, Technology and Research (A*STAR), 10 Biopolis Road, #5-01, 138670, Singapore
| | - Xiaoying Koh
- Experimental Drug Development Centre (EDDC), Agency for Science, Technology and Research (A*STAR), 10 Biopolis Road, #5-01, 138670, Singapore
| | - Weijun Xu
- Experimental Drug Development Centre (EDDC), Agency for Science, Technology and Research (A*STAR), 10 Biopolis Road, #5-01, 138670, Singapore
| | - Joseph Cherian
- Experimental Drug Development Centre (EDDC), Agency for Science, Technology and Research (A*STAR), 10 Biopolis Road, #5-01, 138670, Singapore
| | - Nithya Baburajendran
- Experimental Drug Development Centre (EDDC), Agency for Science, Technology and Research (A*STAR), 10 Biopolis Road, #5-01, 138670, Singapore.
| | - CongBao Kang
- Experimental Drug Development Centre (EDDC), Agency for Science, Technology and Research (A*STAR), 10 Biopolis Road, #5-01, 138670, Singapore.
| | - Zhiyuan Ke
- Experimental Drug Development Centre (EDDC), Agency for Science, Technology and Research (A*STAR), 10 Biopolis Road, #5-01, 138670, Singapore.
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3
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Huang Q, Ng EY, Li Q, Kang C. 1 H, 15 N and 13 C resonance assignments of the Q61H mutant of human KRAS bound to GDP. BIOMOLECULAR NMR ASSIGNMENTS 2022; 16:51-56. [PMID: 34787842 DOI: 10.1007/s12104-021-10058-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Accepted: 11/07/2021] [Indexed: 06/13/2023]
Abstract
KRAS proteins are small GTPases binding to the cell membrane and playing important roles in signal transduction. KRAS proteins form complexes with GTP and GDP to result in active and inactive conformations favouring interactions with different proteins. Mutations in KRAS have impact on the GTPase activity and some mutants are related to certain types of cancers. In addition to mutation at position 12, the Q61H mutant is also identified as an oncogenic mutant. Here, we describe resonance assignment for Q61H mutant of human KRAS-4B. A construct containing 1-169 residues of KRAS with a point mutation at position 61 (Q to H) was made for solution NMR studies. The backbone and some side chain resonance assignments were obtained using conventional multi-dimensional experiments. The secondary structures were analysed based on the assigned residues. As NMR is a powerful tool in probing target and ligand interactions, the assignment will be useful for later compound binding studies.
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Affiliation(s)
- Qiwei Huang
- Experimental Drug Development Centre (EDDC), Agency for Science, Technology and Research (A*STAR), 10 Biopolis Road, Chromos, 05-01, 138670, Singapore
| | - Elizabeth Yihui Ng
- Experimental Drug Development Centre (EDDC), Agency for Science, Technology and Research (A*STAR), 10 Biopolis Road, Chromos, 05-01, 138670, Singapore
| | - Qingxin Li
- Guangdong Provincial Engineering Laboratory of Biomass High Value Utilization, Institute of Biological and Medical Engineering, Guangdong Academy of Sciences, Guangzhou, 510316, China
| | - CongBao Kang
- Experimental Drug Development Centre (EDDC), Agency for Science, Technology and Research (A*STAR), 10 Biopolis Road, Chromos, 05-01, 138670, Singapore.
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4
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Ng HQ, Li Q, Kang C. 1H, 13C and 15N resonance assignments of the first BIR domain of cellular inhibitor of apoptosis protein 1. BIOMOLECULAR NMR ASSIGNMENTS 2022; 16:91-95. [PMID: 35061233 DOI: 10.1007/s12104-022-10065-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 01/04/2022] [Indexed: 06/14/2023]
Abstract
Cellular inhibitor of apoptosis protein-1 (cIAP-1) is member of inhibitor of apoptosis proteins (IAPs) which can affect apoptosis through interactions with caspases. cIAP-1 is a multi-domain protein and able to regulate apoptosis through interactions with proteins such as caspases and possesses E3 ligase activity. Human cIAP-1 contains three baculovirus IAP repeat (BIR) domains which are critical for protein-protein interactions. Here, we report NMR resonance assignments of the first BIR domain of human cIAP. Its secondary structures in solution were determined based on the assigned resonances. The dynamics of this domain was obtained, and our hydrogen-deuterium exchange experiment reveals that the first helix in BIR1 is exposed to the solvent. The availability of assignments of backbone and side chain resonances will be useful for probing protein-protein interactions.
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Affiliation(s)
- Hui Qi Ng
- Experimental Drug Development Centre (EDDC), Agency for Science, Technology and Research (A*STAR), Singapore, 138670, Singapore
| | - Qingxin Li
- Guangdong Provincial Engineering Laboratory of Biomass High Value Utilization, Institute of Biological and Medical Engineering, Guangdong Academy of Sciences, Guangzhou, 510316, China
| | - Congbao Kang
- Experimental Drug Development Centre (EDDC), Agency for Science, Technology and Research (A*STAR), Singapore, 138670, Singapore.
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5
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Li Q, Huang Q, Kang C. Secondary Structures of the Transmembrane Domain of SARS-CoV-2 Spike Protein in Detergent Micelles. Int J Mol Sci 2022; 23:ijms23031040. [PMID: 35162961 PMCID: PMC8834715 DOI: 10.3390/ijms23031040] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 01/08/2022] [Accepted: 01/14/2022] [Indexed: 01/11/2023] Open
Abstract
Spike protein of SARS-CoV-2 contains a single-span transmembrane (TM) domain and plays roles in receptor binding, viral attachment and viral entry to the host cells. The TM domain of spike protein is critical for viral infectivity. Herein, the TM domain of spike protein of SARS-CoV-2 was reconstituted in detergent micelles and subjected to structural analysis using solution NMR spectroscopy. The results demonstrate that the TM domain of the protein forms a helical structure in detergent micelles. An unstructured linker is identified between the TM helix and heptapeptide repeat 2 region. The linker is due to the proline residue at position 1213. Side chains of the three tryptophan residues preceding to and within the TM helix important for the function of S-protein might adopt multiple conformations which may be critical for their function. The side chain of W1212 was shown to be exposed to solvent and the side chains of residues W1214 and W1217 are buried in micelles. Relaxation study shows that the TM helix is rigid in solution while several residues have exchanges. The secondary structure and dynamics of the TM domain in this study provide insights into the function of the TM domain of spike protein.
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Affiliation(s)
- Qingxin Li
- Guangdong Provincial Engineering Laboratory of Biomass High Value Utilization, Institute of Biological and Medical Engineering, Guangdong Academy of Sciences, Guangzhou 510316, China;
| | - Qiwei Huang
- Experimental Drug Development Centre (EDDC), Agency for Science, Technology and Research (A*STAR), Singapore 138670, Singapore;
| | - Congbao Kang
- Experimental Drug Development Centre (EDDC), Agency for Science, Technology and Research (A*STAR), Singapore 138670, Singapore;
- Correspondence:
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6
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Li Y, Ng HQ, Ngo A, Liu S, Tan YW, Kwek PZ, Hung AW, Joy J, Hill J, Keller TH, Kang C. Backbone resonance assignments for the SET domain of human methyltransferase NSD3 in complex with its cofactor. BIOMOLECULAR NMR ASSIGNMENTS 2017; 11:225-229. [PMID: 28808922 DOI: 10.1007/s12104-017-9753-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Accepted: 08/05/2017] [Indexed: 06/07/2023]
Abstract
NSD3 is a histone H3 methyltransferase that plays an important role in chromatin biology. A construct containing the methyltransferase domain encompassing residues Q1049-K1299 of human NSD3 was obtained and biochemical activity was demonstrated using histone as a substrate. Here we report the backbone HN, N, Cα, C', and side chain Cβ assignments of the construct in complex with S-adenosyl-L-methionine (SAM). Based on these assignments, secondary structures of NSD3/SAM complex in solution were determined.
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Affiliation(s)
- Yan Li
- Experimental Therapeutics Centre, Agency for Science, Technology and Research, 31 Biopolis Way Nanos, #03-01, Singapore, 138669, Singapore
| | - Hui Qi Ng
- Experimental Therapeutics Centre, Agency for Science, Technology and Research, 31 Biopolis Way Nanos, #03-01, Singapore, 138669, Singapore
| | - Anna Ngo
- Experimental Therapeutics Centre, Agency for Science, Technology and Research, 31 Biopolis Way Nanos, #03-01, Singapore, 138669, Singapore
| | - Shuang Liu
- Experimental Therapeutics Centre, Agency for Science, Technology and Research, 31 Biopolis Way Nanos, #03-01, Singapore, 138669, Singapore
| | - Yih Wan Tan
- Experimental Therapeutics Centre, Agency for Science, Technology and Research, 31 Biopolis Way Nanos, #03-01, Singapore, 138669, Singapore
| | - Perlyn Zekui Kwek
- Experimental Therapeutics Centre, Agency for Science, Technology and Research, 31 Biopolis Way Nanos, #03-01, Singapore, 138669, Singapore
| | - Alvin W Hung
- Experimental Therapeutics Centre, Agency for Science, Technology and Research, 31 Biopolis Way Nanos, #03-01, Singapore, 138669, Singapore
| | - Joma Joy
- Experimental Therapeutics Centre, Agency for Science, Technology and Research, 31 Biopolis Way Nanos, #03-01, Singapore, 138669, Singapore
| | - Jeffrey Hill
- Experimental Therapeutics Centre, Agency for Science, Technology and Research, 31 Biopolis Way Nanos, #03-01, Singapore, 138669, Singapore
| | - Thomas H Keller
- Experimental Therapeutics Centre, Agency for Science, Technology and Research, 31 Biopolis Way Nanos, #03-01, Singapore, 138669, Singapore
| | - CongBao Kang
- Experimental Therapeutics Centre, Agency for Science, Technology and Research, 31 Biopolis Way Nanos, #03-01, Singapore, 138669, Singapore.
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7
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Li Y, Ng HQ, Li Q, Kang C. Structure of the Cyclic Nucleotide-Binding Homology Domain of the hERG Channel and Its Insight into Type 2 Long QT Syndrome. Sci Rep 2016; 6:23712. [PMID: 27025590 PMCID: PMC4812329 DOI: 10.1038/srep23712] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Accepted: 03/14/2016] [Indexed: 01/09/2023] Open
Abstract
The human ether-à-go-go related gene (hERG) channel is crucial for the cardiac action potential by contributing to the fast delayed-rectifier potassium current. Mutations in the hERG channel result in type 2 long QT syndrome (LQT2). The hERG channel contains a cyclic nucleotide-binding homology domain (CNBHD) and this domain is required for the channel gating though molecular interactions with the eag domain. Here we present solution structure of the CNBHD of the hERG channel. The structural study reveals that the CNBHD adopts a similar fold to other KCNH channels. It is self-liganded and it contains a short β-strand that blocks the nucleotide-binding pocket in the β-roll. Folding of LQT2-related mutations in this domain was shown to be affected by point mutation. Mutations in this domain can cause protein aggregation in E. coli cells or induce conformational changes. One mutant-R752W showed obvious chemical shift perturbation compared with the wild-type, but it still binds to the eag domain. The helix region from the N-terminal cap domain of the hERG channel showed unspecific interactions with the CNBHD.
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Affiliation(s)
- Yan Li
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
| | - Hui Qi Ng
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
| | - Qingxin Li
- Institute of Chemical &Engineering Sciences, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
| | - CongBao Kang
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
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8
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Li Y, Wong YX, Poh ZY, Wong YL, Lee MY, Ng HQ, Liu B, Hung AW, Cherian J, Hill J, Keller TH, Kang C. NMR structural characterization of the N-terminal active domain of the gyrase B subunit from Pseudomonas aeruginosa and its complex with an inhibitor. FEBS Lett 2015; 589:2683-9. [PMID: 26272827 DOI: 10.1016/j.febslet.2015.07.044] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Revised: 07/08/2015] [Accepted: 07/26/2015] [Indexed: 01/18/2023]
Abstract
The N-terminal ATP binding domain of the DNA gyrase B subunit is a validated drug target for antibacterial drug discovery. Structural information for this domain (pGyrB) from Pseudomonas aeruginosa is still missing. In this study, the interaction between pGyrB and a bis-pyridylurea inhibitor was characterized using several biophysical methods. We further carried out structural analysis of pGyrB using NMR spectroscopy. The secondary structures of free and inhibitor bound pGyrB were obtained based on backbone chemical shift assignment. Chemical shift perturbation and NOE experiments demonstrated that the inhibitor binds to the ATP binding pocket. The results of this study will be helpful for drug development targeting P. aeruginosa.
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Affiliation(s)
- Yan Li
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos, #03-01, Singapore 138669, Singapore
| | - Yun Xuan Wong
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos, #03-01, Singapore 138669, Singapore
| | - Zhi Ying Poh
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos, #03-01, Singapore 138669, Singapore
| | - Ying Lei Wong
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos, #03-01, Singapore 138669, Singapore
| | - Michelle Yueqi Lee
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos, #03-01, Singapore 138669, Singapore
| | - Hui Qi Ng
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos, #03-01, Singapore 138669, Singapore
| | - Boping Liu
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos, #03-01, Singapore 138669, Singapore
| | - Alvin W Hung
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos, #03-01, Singapore 138669, Singapore
| | - Joseph Cherian
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos, #03-01, Singapore 138669, Singapore
| | - Jeffrey Hill
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos, #03-01, Singapore 138669, Singapore
| | - Thomas H Keller
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos, #03-01, Singapore 138669, Singapore
| | - CongBao Kang
- Experimental Therapeutics Centre, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, Nanos, #03-01, Singapore 138669, Singapore.
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9
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Perry MD, Ng CA, Mann SA, Sadrieh A, Imtiaz M, Hill AP, Vandenberg JI. Getting to the heart of hERG K(+) channel gating. J Physiol 2015; 593:2575-85. [PMID: 25820318 PMCID: PMC4500344 DOI: 10.1113/jp270095] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Accepted: 03/13/2015] [Indexed: 12/24/2022] Open
Abstract
Potassium ion channels encoded by the human ether-a-go-go related gene (hERG) form the ion-conducting subunit of the rapid delayed rectifier potassium current (IKr ). Although hERG channels exhibit a widespread tissue distribution they play a particularly important role in the heart. There has been considerable interest in hERG K(+) channels for three main reasons. First, they have very unusual gating kinetics, most notably rapid and voltage-dependent inactivation coupled to slow deactivation, which has led to the suggestion that they may play a specific role in the suppression of arrhythmias. Second, mutations in hERG are the cause of 30-40% of cases of congenital long QT syndrome (LQTS), the commonest inherited primary arrhythmia syndrome. Third, hERG is the molecular target for the vast majority of drugs that cause drug-induced LQTS, the commonest cause of drug-induced arrhythmias and cardiac death. Drug-induced LQTS has now been reported for a large range of both cardiac and non-cardiac drugs, in which this side effect is entirely undesired. In recent years there have been comprehensive reviews published on hERG K(+) channels (Vandenberg et al. 2012) and we will not re-cover this ground. Rather, we focus on more recent work on the structural basis and dynamics of hERG gating with an emphasis on how the latest developments may facilitate translational research in the area of stratifying risk of arrhythmias.
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Affiliation(s)
- Matthew D Perry
- Victor Chang Cardiac Research Institute405 Liverpool Street, Darlinghurst, NSW 2010, Australia
- St Vincent’s Clinical School, University of NSWDarlinghurst, NSW 2010, Australia
| | - Chai-Ann Ng
- Victor Chang Cardiac Research Institute405 Liverpool Street, Darlinghurst, NSW 2010, Australia
- St Vincent’s Clinical School, University of NSWDarlinghurst, NSW 2010, Australia
| | - Stefan A Mann
- Victor Chang Cardiac Research Institute405 Liverpool Street, Darlinghurst, NSW 2010, Australia
- St Vincent’s Clinical School, University of NSWDarlinghurst, NSW 2010, Australia
| | - Arash Sadrieh
- Victor Chang Cardiac Research Institute405 Liverpool Street, Darlinghurst, NSW 2010, Australia
- St Vincent’s Clinical School, University of NSWDarlinghurst, NSW 2010, Australia
| | - Mohammad Imtiaz
- Victor Chang Cardiac Research Institute405 Liverpool Street, Darlinghurst, NSW 2010, Australia
- St Vincent’s Clinical School, University of NSWDarlinghurst, NSW 2010, Australia
| | - Adam P Hill
- Victor Chang Cardiac Research Institute405 Liverpool Street, Darlinghurst, NSW 2010, Australia
- St Vincent’s Clinical School, University of NSWDarlinghurst, NSW 2010, Australia
| | - Jamie I Vandenberg
- Victor Chang Cardiac Research Institute405 Liverpool Street, Darlinghurst, NSW 2010, Australia
- St Vincent’s Clinical School, University of NSWDarlinghurst, NSW 2010, Australia
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10
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Insight into the molecular interaction between the cyclic nucleotide-binding homology domain and the eag domain of the hERG channel. FEBS Lett 2014; 588:2782-8. [PMID: 24931372 DOI: 10.1016/j.febslet.2014.05.056] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Revised: 05/14/2014] [Accepted: 05/27/2014] [Indexed: 12/18/2022]
Abstract
The gating of the hERG channel is regulated by its eag domain through molecular interaction with either the cyclic nucleotide-binding homology domain (CNBHD) or the linker between transmembrane segments 4 and 5. Our NMR study on the purified CNBHD demonstrated that it contains nine β-strands and does not bind cAMP. We show that the eag domain binds to the CBND through an interface containing several disease-associated mutations. The N-terminal cap domain and R56 in the eag domain are important for the interaction with the CNBHD. Residues from the CNBHD that were affected by the interaction with the eag domain were also identified. A R56Q mutation does not cause major structural changes in the eag domain and showed reduced interaction with the CNBHD.
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