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Sanches K, Ashwood LM, Olushola-Siedoks AAM, Wai DCC, Rahman A, Shakeel K, Naseem MU, Panyi G, Prentis PJ, Norton RS. Structure-function relationships in ShKT domain peptides: ShKT-Ts1 from the sea anemone Telmatactis stephensoni. Proteins 2024; 92:192-205. [PMID: 37794633 DOI: 10.1002/prot.26594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2023] [Revised: 08/14/2023] [Accepted: 09/07/2023] [Indexed: 10/06/2023]
Abstract
Diverse structural scaffolds have been described in peptides from sea anemones, with the ShKT domain being a common scaffold first identified in ShK toxin from Stichodactyla helianthus. ShK is a potent blocker of voltage-gated potassium channels (KV 1.x), and an analog, ShK-186 (dalazatide), has completed Phase 1 clinical trials in plaque psoriasis. The ShKT domain has been found in numerous other species, but only a tiny fraction of ShKT domains has been characterized functionally. Despite adopting the canonical ShK fold, some ShKT peptides from sea anemones inhibit KV 1.x, while others do not. Mutagenesis studies have shown that a Lys-Tyr (KY) dyad plays a key role in KV 1.x blockade, although a cationic residue followed by a hydrophobic residue may also suffice. Nevertheless, ShKT peptides displaying an ShK-like fold and containing a KY dyad do not necessarily block potassium channels, so additional criteria are needed to determine whether new ShKT peptides might show activity against potassium channels. In this study, we used a combination of NMR and molecular dynamics (MD) simulations to assess the potential activity of a new ShKT peptide. We determined the structure of ShKT-Ts1, from the sea anemone Telmatactis stephensoni, examined its tissue localization, and investigated its activity against a range of ion channels. As ShKT-Ts1 showed no activity against KV 1.x channels, we used MD simulations to investigate whether solvent exposure of the dyad residues may be informative in rationalizing and potentially predicting the ability of ShKT peptides to block KV 1.x channels. We show that either a buried dyad that does not become exposed during MD simulations, or a partially exposed dyad that becomes buried during MD simulations, correlates with weak or absent activity against KV 1.x channels. Therefore, structure determination coupled with MD simulations, may be used to predict whether new sequences belonging to the ShKT family may act as potassium channel blockers.
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Affiliation(s)
- Karoline Sanches
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia
- ARC Centre for Fragment-Based Design, Monash University, Parkville, Victoria, Australia
| | - Lauren M Ashwood
- School of Biology and Environmental Science, Faculty of Science, Queensland University of Technology, Brisbane, Queensland, Australia
| | | | - Dorothy C C Wai
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia
| | - Arfatur Rahman
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia
| | - Kashmala Shakeel
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Muhammad Umair Naseem
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Gyorgy Panyi
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Peter J Prentis
- School of Biology and Environmental Science, Faculty of Science, Queensland University of Technology, Brisbane, Queensland, Australia
- Centre for Agriculture and the Bioeconomy, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Raymond S Norton
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia
- ARC Centre for Fragment-Based Design, Monash University, Parkville, Victoria, Australia
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Elnahriry KA, Wai DCC, Ashwood LM, Naseem MU, Szanto TG, Guo S, Panyi G, Prentis PJ, Norton RS. Structural and functional characterisation of Tst2, a novel TRPV1 inhibitory peptide from the Australian sea anemone Telmatactis stephensoni. Biochim Biophys Acta Proteins Proteom 2024; 1872:140952. [PMID: 37640250 DOI: 10.1016/j.bbapap.2023.140952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 08/15/2023] [Accepted: 08/25/2023] [Indexed: 08/31/2023]
Abstract
Sea anemone venoms are complex mixtures of biologically active compounds, including disulfide-rich peptides, some of which have found applications as research tools, and others as therapeutic leads. Our recent transcriptomic and proteomic studies of the Australian sea anemone Telmatactis stephensoni identified a transcript for a peptide designated Tst2. Tst2 is a 38-residue peptide showing sequence similarity to peptide toxins known to interact with a range of ion channels (NaV, TRPV1, KV and CaV). Recombinant Tst2 (rTst2, which contains an additional Gly at the N-terminus) was produced by periplasmic expression in Escherichia coli, enabling the production of both unlabelled and uniformly 13C,15N-labelled peptide for functional assays and structural studies. The LC-MS profile of the recombinant Tst2 showed a pure peak with molecular mass 6 Da less than that of the reduced form of the peptide, indicating the successful formation of three disulfide bonds from its six cysteine residues. The solution structure of rTst2 was determined using multidimensional NMR spectroscopy and revealed that rTst2 adopts an inhibitor cystine knot (ICK) structure. rTst2 was screened using various functional assays, including patch-clamp electrophysiological and cytotoxicity assays. rTst2 was inactive against voltage-gated sodium channels (NaV) and the human voltage-gated proton (hHv1) channel. rTst2 also did not possess cytotoxic activity when assessed against Drosophila melanogaster flies. However, the recombinant peptide at 100 nM showed >50% inhibition of the transient receptor potential subfamily V member 1 (TRPV1) and slight (∼10%) inhibition of transient receptor potential subfamily A member 1 (TRPA1). Tst2 is thus a novel ICK inhibitor of the TRPV1 channel.
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Affiliation(s)
- Khaled A Elnahriry
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC 3052, Australia
| | - Dorothy C C Wai
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC 3052, Australia
| | - Lauren M Ashwood
- School of Biology and Environmental Science, Faculty of Science, Queensland University of Technology, Brisbane, QLD 4000, Australia
| | - Muhammad Umair Naseem
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, Debrecen 4032, Hungary
| | - Tibor G Szanto
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, Debrecen 4032, Hungary
| | - Shaodong Guo
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Gyorgy Panyi
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, Debrecen 4032, Hungary
| | - Peter J Prentis
- School of Biology and Environmental Science, Faculty of Science, Queensland University of Technology, Brisbane, QLD 4000, Australia; Centre for Agriculture and the Bioeconomy, Queensland University of Technology, Brisbane, QLD 4000, Australia
| | - Raymond S Norton
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC 3052, Australia; ARC Centre for Fragment-Based Design, Monash University, Parkville, VIC 3052, Australia.
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Jose J, Law RHP, Leung EWW, Wai DCC, Akhlaghi H, Chandrashekaran IR, Caradoc-Davies TT, Voskoboinik I, Feutrill J, Middlemiss D, Jeevarajah D, Bashtannyk-Puhalovich T, Giddens AC, Lee TW, Jamieson SMF, Trapani JA, Whisstock JC, Spicer JA, Norton RS. Fragment-based and structure-guided discovery of perforin inhibitors. Eur J Med Chem 2023; 261:115786. [PMID: 37716187 DOI: 10.1016/j.ejmech.2023.115786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 08/24/2023] [Accepted: 08/31/2023] [Indexed: 09/18/2023]
Abstract
Perforin is a pore-forming protein whose normal function enables cytotoxic T and natural killer (NK) cells to kill virus-infected and transformed cells. Conversely, unwanted perforin activity can also result in auto-immune attack, graft rejection and aberrant responses to pathogens. Perforin is critical for the function of the granule exocytosis cell death pathway and is therefore a target for drug development. In this study, by screening a fragment library using NMR and surface plasmon resonance, we identified 4,4-diaminodiphenyl sulfone (dapsone) as a perforin ligand. We also found that dapsone has modest (mM) inhibitory activity of perforin lytic activity in a red blood cell lysis assay in vitro. Sequential modification of this lead fragment, guided by structural knowledge of the ligand binding site and binding pose, and supported by SPR and ligand-detected 19F NMR, enabled the design of nanomolar inhibitors of the cytolytic activity of intact NK cells against various tumour cell targets. Interestingly, the ligands we developed were largely inert with respect to direct perforin-mediated red blood cell lysis but were very potent in the context of perforin's action on delivering granzymes in the immune synapse, the context in which it functions physiologically. Our work indicates that a fragment-based, structure-guided drug discovery strategy can be used to identify novel ligands that bind perforin. Moreover, these molecules have superior physicochemical properties and solubility compared to previous generations of perforin ligands.
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Affiliation(s)
- Jiney Jose
- Auckland Cancer Society Research Centre, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, A New Zealand Centre for Research Excellence, Auckland, New Zealand
| | - Ruby H P Law
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, 3800, Australia
| | - Eleanor W W Leung
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, 3052, Australia
| | - Dorothy C C Wai
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, 3052, Australia
| | - Hedieh Akhlaghi
- Cancer Immunology Program, Peter MacCallum Cancer Centre, 305 Grattan Street, Melbourne, VIC, 3000, Australia; Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, VIC, 3052, Australia
| | - Indu R Chandrashekaran
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, 3052, Australia; ARC Centre for Fragment-Based Design, Monash University, Parkville, VIC, 3052, Australia
| | - Tom T Caradoc-Davies
- Australian Synchrotron, 800 Blackburn Rd., Clayton, Melbourne, VIC, 3168, Australia
| | - Ilia Voskoboinik
- Cancer Immunology Program, Peter MacCallum Cancer Centre, 305 Grattan Street, Melbourne, VIC, 3000, Australia; Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, VIC, 3052, Australia
| | - John Feutrill
- SYNthesis med chem (Australia) Pty Ltd, Bio21 Institute, 30 Flemington Road, Parkville, VIC, 3052, Australia
| | - David Middlemiss
- XaviaPharm, Bishop's Stortford, CM23 5EX, England, United Kingdom
| | - Devadharshini Jeevarajah
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, 3800, Australia
| | | | - Anna C Giddens
- Auckland Cancer Society Research Centre, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand
| | - Tet Woo Lee
- Auckland Cancer Society Research Centre, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand
| | - Stephen M F Jamieson
- Auckland Cancer Society Research Centre, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, A New Zealand Centre for Research Excellence, Auckland, New Zealand; Department of Pharmacology and Clinical Pharmacology, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand
| | - Joseph A Trapani
- Cancer Immunology Program, Peter MacCallum Cancer Centre, 305 Grattan Street, Melbourne, VIC, 3000, Australia; Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, VIC, 3052, Australia
| | - James C Whisstock
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, 3800, Australia.
| | - Julie A Spicer
- Auckland Cancer Society Research Centre, Faculty of Medical and Health Sciences, The University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, A New Zealand Centre for Research Excellence, Auckland, New Zealand.
| | - Raymond S Norton
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, 3052, Australia; ARC Centre for Fragment-Based Design, Monash University, Parkville, VIC, 3052, Australia.
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Pan Y, Kagawa Y, Sun J, Lucas DSD, Takechi R, Mamo JCL, Wai DCC, Norton RS, Jin L, Nicolazzo JA. Peripheral Administration of the Kv1.3-Blocking Peptide HsTX1[R14A] Improves Cognitive Performance in Senescence Accelerated SAMP8 Mice. Neurotherapeutics 2023; 20:1198-1214. [PMID: 37226029 PMCID: PMC10457257 DOI: 10.1007/s13311-023-01387-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/24/2023] [Indexed: 05/26/2023] Open
Abstract
Increased expression of the voltage-gated potassium channel Kv1.3 in activated microglia, and the subsequent release of pro-inflammatory mediators, are closely associated with the progression of Alzheimer's disease (AD). Studies have shown that reducing neuroinflammation through the non-selective blockade of microglial Kv1.3 has the potential to improve cognitive function in mouse models of familial AD. We have previously demonstrated that a potent and highly-selective peptide blocker of Kv1.3, HsTX1[R14A], not only entered the brain parenchyma after peripheral administration in a lipopolysaccharide (LPS)-induced mouse model of inflammation, but also significantly reduced pro-inflammatory mediator release from activated microglia. In this study, we show that microglial expression of Kv1.3 is increased in senescence accelerated mice (SAMP8), an animal model of sporadic AD, and that subcutaneous dosing of HsTX1[R14A] (1 mg/kg) every other day for 8 weeks provided a robust improvement in cognitive deficits in SAMP8 mice. The effect of HsTX1[R14A] on the whole brain was assessed using transcriptomics, which revealed that the expression of genes associated with inflammation, neuron differentiation, synapse function, learning and memory were altered by HsTX1[R14A] treatment. Further study is required to investigate whether these changes are downstream effects of microglial Kv1.3 blockade or a result of alternative mechanisms, including any potential effect of Kv1.3 blockade on other brain cell types. Nonetheless, these results collectively demonstrate the cognitive benefits of Kv1.3 blockade with HsTX1[R14A] in a mouse model of sporadic AD, demonstrating its potential as a therapeutic candidate for this neurodegenerative disease.
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Affiliation(s)
- Yijun Pan
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, 3052, Australia
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, 3052, Australia
- Department of Organ Anatomy, Graduate School of Medicine, Tohoku University, Sendai, Miyagi, 980-8575, Japan
| | - Yoshiteru Kagawa
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, 3052, Australia
- Department of Organ Anatomy, Graduate School of Medicine, Tohoku University, Sendai, Miyagi, 980-8575, Japan
| | - Jiaqi Sun
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, 3052, Australia
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, 3052, Australia
| | - Deanna S Deveson Lucas
- Monash Bioinformatics Platform, Biomedicine Discovery Institute, Monash University, Clayton, VIC, 3800, Australia
| | - Ryusuke Takechi
- School of Biomedical Sciences, Curtin University, Bentley, WA, 6102, Australia
- School of Public Health, Curtin University, Bentley, WA, 6102, Australia
| | - John C L Mamo
- School of Biomedical Sciences, Curtin University, Bentley, WA, 6102, Australia
- School of Public Health, Curtin University, Bentley, WA, 6102, Australia
| | - Dorothy C C Wai
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, 3052, Australia
| | - Raymond S Norton
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, 3052, Australia
- ARC Centre for Fragment-Based Design, Monash University, Parkville, VIC, 3052, Australia
| | - Liang Jin
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, 3052, Australia.
| | - Joseph A Nicolazzo
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, 3052, Australia.
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Ashwood LM, Elnahriry KA, Stewart ZK, Shafee T, Naseem MU, Szanto TG, van der Burg CA, Smith HL, Surm JM, Undheim EAB, Madio B, Hamilton BR, Guo S, Wai DCC, Coyne VL, Phillips MJ, Dudley KJ, Hurwood DA, Panyi G, King GF, Pavasovic A, Norton RS, Prentis PJ. Genomic, functional and structural analyses elucidate evolutionary innovation within the sea anemone 8 toxin family. BMC Biol 2023; 21:121. [PMID: 37226201 DOI: 10.1186/s12915-023-01617-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2023] [Accepted: 05/09/2023] [Indexed: 05/26/2023] Open
Abstract
BACKGROUND The ShK toxin from Stichodactyla helianthus has established the therapeutic potential of sea anemone venom peptides, but many lineage-specific toxin families in Actiniarians remain uncharacterised. One such peptide family, sea anemone 8 (SA8), is present in all five sea anemone superfamilies. We explored the genomic arrangement and evolution of the SA8 gene family in Actinia tenebrosa and Telmatactis stephensoni, characterised the expression patterns of SA8 sequences, and examined the structure and function of SA8 from the venom of T. stephensoni. RESULTS We identified ten SA8-family genes in two clusters and six SA8-family genes in five clusters for T. stephensoni and A. tenebrosa, respectively. Nine SA8 T. stephensoni genes were found in a single cluster, and an SA8 peptide encoded by an inverted SA8 gene from this cluster was recruited to venom. We show that SA8 genes in both species are expressed in a tissue-specific manner and the inverted SA8 gene has a unique tissue distribution. While the functional activity of the SA8 putative toxin encoded by the inverted gene was inconclusive, its tissue localisation is similar to toxins used for predator deterrence. We demonstrate that, although mature SA8 putative toxins have similar cysteine spacing to ShK, SA8 peptides are distinct from ShK peptides based on structure and disulfide connectivity. CONCLUSIONS Our results provide the first demonstration that SA8 is a unique gene family in Actiniarians, evolving through a variety of structural changes including tandem and proximal gene duplication and an inversion event that together allowed SA8 to be recruited into the venom of T. stephensoni.
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Affiliation(s)
- Lauren M Ashwood
- School of Biology and Environmental Science, Faculty of Science, Queensland University of Technology, Brisbane, QLD, 4000, Australia.
- Cancer Program, QIMR Berghofer Medical Research Institute, Brisbane, QLD, 4006, Australia.
| | - Khaled A Elnahriry
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, 3052, Australia
| | - Zachary K Stewart
- Centre for Agriculture and the Bioeconomy, Queensland University of Technology, Brisbane, QLD, 4000, Australia
| | - Thomas Shafee
- Department of Animal Plant & Soil Sciences, La Trobe University, Melbourne, Australia
- Swinburne University of Technology, Melbourne, VIC, Australia
| | - Muhammad Umair Naseem
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, 4032, Debrecen, Hungary
| | - Tibor G Szanto
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, 4032, Debrecen, Hungary
| | - Chloé A van der Burg
- School of Biology and Environmental Science, Faculty of Science, Queensland University of Technology, Brisbane, QLD, 4000, Australia
- Department of Anatomy, School of Biomedical Sciences, University of Otago, Dunedin, 9016, New Zealand
| | - Hayden L Smith
- School of Biology and Environmental Science, Faculty of Science, Queensland University of Technology, Brisbane, QLD, 4000, Australia
| | - Joachim M Surm
- Department of Ecology, Evolution and Behavior, Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, 9190401, Jerusalem, Israel
| | - Eivind A B Undheim
- Department of Biosciences, Centre for Ecological and Evolutionary Synthesis, University of Oslo, Blindern, PO Box 1066, 0316, Oslo, Norway
- Centre for Advanced Imaging, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Bruno Madio
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Brett R Hamilton
- Centre for Advanced Imaging, The University of Queensland, St Lucia, QLD, 4072, Australia
- Centre for Microscopy and Microanalysis, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Shaodong Guo
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Dorothy C C Wai
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, 3052, Australia
| | - Victoria L Coyne
- Research Infrastructure, Central Analytical Research Facility, Queensland University of Technology, Brisbane, QLD, 4000, Australia
| | - Matthew J Phillips
- School of Biology and Environmental Science, Faculty of Science, Queensland University of Technology, Brisbane, QLD, 4000, Australia
| | - Kevin J Dudley
- School of Biology and Environmental Science, Faculty of Science, Queensland University of Technology, Brisbane, QLD, 4000, Australia
- Research Infrastructure, Central Analytical Research Facility, Queensland University of Technology, Brisbane, QLD, 4000, Australia
| | - David A Hurwood
- School of Biology and Environmental Science, Faculty of Science, Queensland University of Technology, Brisbane, QLD, 4000, Australia
- Centre for Agriculture and the Bioeconomy, Queensland University of Technology, Brisbane, QLD, 4000, Australia
| | - Gyorgy Panyi
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, 4032, Debrecen, Hungary
| | - Glenn F King
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, 4072, Australia
- ARC Centre for Innovations in Peptide and Protein Science, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Ana Pavasovic
- School of Biomedical Sciences, Faculty of Health, Queensland University of Technology, Brisbane, QLD, 4000, Australia
| | - Raymond S Norton
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, 3052, Australia
- ARC Centre for Fragment-Based Design, Monash University, Parkville, VIC, 3052, Australia
| | - Peter J Prentis
- School of Biology and Environmental Science, Faculty of Science, Queensland University of Technology, Brisbane, QLD, 4000, Australia
- Centre for Agriculture and the Bioeconomy, Queensland University of Technology, Brisbane, QLD, 4000, Australia
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Reddiar SB, de Veer M, Paterson BM, Sepehrizadeh T, Wai DCC, Csoti A, Panyi G, Nicolazzo JA, Norton RS. A Biodistribution Study of the Radiolabeled Kv1.3-Blocking Peptide DOTA-HsTX1[R14A] Demonstrates Brain Uptake in a Mouse Model of Neuroinflammation. Mol Pharm 2023; 20:255-266. [PMID: 36331024 DOI: 10.1021/acs.molpharmaceut.2c00614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The voltage-gated potassium channel Kv1.3 regulates the pro-inflammatory function of microglia and is highly expressed in the post-mortem brains of individuals with Alzheimer's and Parkinson's diseases. HsTX1[R14A] is a selective and potent peptide inhibitor of the Kv1.3 channel (IC50 ∼ 45 pM) that has been shown to decrease cytokine levels in a lipopolysaccharide (LPS)-induced mouse model of inflammation. Central nervous system exposure to HsTX1[R14A] was previously detected in this mouse model using liquid chromatography with tandem mass spectrometry, but this technique does not report on the spatial distribution of the peptide in the different brain regions or peripheral organs. Herein, the in vivo distribution of a [64Cu]Cu-labeled DOTA conjugate of HsTX1[R14A] was observed for up to 48 h by positron emission tomography (PET) in mice. After subcutaneous administration to untreated C57BL/6J mice, considerable uptake of the radiolabeled peptide was observed in the kidney, but it was undetectable in the brain. Biodistribution of a [68Ga]Ga-DOTA conjugate of HsTX1[R14A] was then investigated in the LPS-induced mouse model of neuroinflammation to assess the effects of inflammation on uptake of the peptide in the brain. A control peptide with very weak Kv1.3 binding, [68Ga]Ga-DOTA-HsTX1[R14A,Y21A,K23A] (IC50 ∼ 6 μM), was also tested. Significantly increased uptake of [68Ga]Ga-DOTA-HsTX1[R14A] was observed in the brains of LPS-treated mice compared to mice treated with control peptide, implying that the enhanced uptake was due to increased Kv1.3 expression rather than simply increased blood-brain barrier disruption. PET imaging also showed accumulation of [68Ga]Ga-DOTA-HsTX1[R14A] in inflamed joints and decreased clearance from the kidneys in LPS-treated mice. These biodistribution data highlight the potential of HsTX1[R14A] as a therapeutic for the treatment of neuroinflammatory diseases mediated by overexpression of Kv1.3.
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Affiliation(s)
- Sanjeevini Babu Reddiar
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, Victoria 3052, Australia
| | - Michael de Veer
- Monash Biomedical Imaging, Monash University, Melbourne, Victoria 3800, Australia
| | - Brett M Paterson
- Monash Biomedical Imaging, Monash University, Melbourne, Victoria 3800, Australia.,School of Chemistry, Monash University, Clayton, Victoria 3800, Australia
| | - Tara Sepehrizadeh
- Monash Biomedical Imaging, Monash University, Melbourne, Victoria 3800, Australia
| | - Dorothy C C Wai
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, Victoria 3052, Australia
| | - Agota Csoti
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, Debrecen 4010, Hungary
| | - Gyorgy Panyi
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, Debrecen 4010, Hungary
| | - Joseph A Nicolazzo
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, Victoria 3052, Australia
| | - Raymond S Norton
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, Victoria 3052, Australia.,ARC Centre for Fragment-Based Design, Monash University, Parkville, Victoria 3052, Australia
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7
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Wai DCC, Naseem MU, Mocsár G, Babu Reddiar S, Pan Y, Csoti A, Hajdu P, Nowell C, Nicolazzo JA, Panyi G, Norton RS. Fluorescent Peptide Toxin for Selective Visualization of the Voltage-Gated Potassium Channel K V1.3. Bioconjug Chem 2022; 33:2197-2212. [DOI: 10.1021/acs.bioconjchem.2c00436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Dorothy C. C. Wai
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria3052, Australia
| | - Muhammad Umair Naseem
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, Debrecen4032, Hungary
| | - Gábor Mocsár
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, Debrecen4032, Hungary
- Damjanovich Cell Analysis Core Facility, Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, Debrecen4032, Hungary
| | - Sanjeevini Babu Reddiar
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria3052, Australia
| | - Yijun Pan
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria3052, Australia
| | - Agota Csoti
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, Debrecen4032, Hungary
| | - Peter Hajdu
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, Debrecen4032, Hungary
- Department of Dental Biochemistry, Faculty of Dentistry, University of Debrecen, Debrecen4032, Hungary
| | - Cameron Nowell
- Imaging, FACS and Analysis Core, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria3052, Australia
| | - Joseph A. Nicolazzo
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria3052, Australia
| | - Gyorgy Panyi
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, Debrecen4032, Hungary
| | - Raymond S. Norton
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria3052, Australia
- ARC Centre for Fragment-Based Design, Monash University, Parkville, Victoria3052, Australia
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8
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Mitchell ML, Hossain MA, Lin F, Pinheiro-Junior EL, Peigneur S, Wai DCC, Delaine C, Blyth AJ, Forbes BE, Tytgat J, Wade JD, Norton RS. Identification, Synthesis, Conformation and Activity of an Insulin-like Peptide from a Sea Anemone. Biomolecules 2021; 11:1785. [PMID: 34944429 PMCID: PMC8698791 DOI: 10.3390/biom11121785] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 10/28/2021] [Accepted: 11/23/2021] [Indexed: 12/24/2022] Open
Abstract
The role of insulin and insulin-like peptides (ILPs) in vertebrate animals is well studied. Numerous ILPs are also found in invertebrates, although there is uncertainty as to the function and role of many of these peptides. We have identified transcripts with similarity to the insulin family in the tentacle transcriptomes of the sea anemone Oulactis sp. (Actiniaria: Actiniidae). The translated transcripts showed that these insulin-like peptides have highly conserved A- and B-chains among individuals of this species, as well as other Anthozoa. An Oulactis sp. ILP sequence (IlO1_i1) was synthesized using Fmoc solid-phase peptide synthesis of the individual chains, followed by regioselective disulfide bond formation of the intra-A and two interchain disulfide bonds. Bioactivity studies of IlO1_i1 were conducted on human insulin and insulin-like growth factor receptors, and on voltage-gated potassium, sodium, and calcium channels. IlO1_i1 did not bind to the insulin or insulin-like growth factor receptors, but showed weak activity against KV1.2, 1.3, 3.1, and 11.1 (hERG) channels, as well as NaV1.4 channels. Further functional studies are required to determine the role of this peptide in the sea anemone.
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Affiliation(s)
- Michela L. Mitchell
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia;
- Sciences Department, Museum Victoria, G.P.O. Box 666, Melbourne, VIC 3001, Australia
- Biodiversity and Geosciences, Queensland Museum, P.O. Box 3000, South Brisbane, QLD 4101, Australia
| | - Mohammed Akhter Hossain
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC 3010, Australia; (M.A.H.); (F.L.); (J.D.W.)
- School of Chemistry, University of Melbourne, Parkville, VIC 3010, Australia
| | - Feng Lin
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC 3010, Australia; (M.A.H.); (F.L.); (J.D.W.)
| | - Ernesto L. Pinheiro-Junior
- Toxicology and Pharmacology, University of Leuven, O&N 2, Herestraat 49, P.O. Box 922, 3000 Leuven, Belgium; (E.L.P.-J.); (S.P.); (J.T.)
| | - Steve Peigneur
- Toxicology and Pharmacology, University of Leuven, O&N 2, Herestraat 49, P.O. Box 922, 3000 Leuven, Belgium; (E.L.P.-J.); (S.P.); (J.T.)
| | - Dorothy C. C. Wai
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia;
| | - Carlie Delaine
- Flinders Health and Medical Research Institute, Flinders University, Bedford Park, SA 5042, Australia; (C.D.); (A.J.B.); (B.E.F.)
| | - Andrew J. Blyth
- Flinders Health and Medical Research Institute, Flinders University, Bedford Park, SA 5042, Australia; (C.D.); (A.J.B.); (B.E.F.)
| | - Briony E. Forbes
- Flinders Health and Medical Research Institute, Flinders University, Bedford Park, SA 5042, Australia; (C.D.); (A.J.B.); (B.E.F.)
| | - Jan Tytgat
- Toxicology and Pharmacology, University of Leuven, O&N 2, Herestraat 49, P.O. Box 922, 3000 Leuven, Belgium; (E.L.P.-J.); (S.P.); (J.T.)
| | - John D. Wade
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC 3010, Australia; (M.A.H.); (F.L.); (J.D.W.)
- School of Chemistry, University of Melbourne, Parkville, VIC 3010, Australia
| | - Raymond S. Norton
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia;
- ARC Centre for Fragment-Based Design, Monash University, Parkville, VIC 3052, Australia
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9
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Nicolazzo JA, Pan Y, Di Stefano I, Choy KHC, Reddiar SB, Low YL, Wai DCC, Norton RS, Jin L. Blockade of Microglial Kv1.3 Potassium Channels by the Peptide HsTX1[R14A] Attenuates Lipopolysaccharide-mediated Neuroinflammation. J Pharm Sci 2021; 111:638-647. [PMID: 34767826 DOI: 10.1016/j.xphs.2021.11.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 11/03/2021] [Accepted: 11/03/2021] [Indexed: 12/19/2022]
Abstract
The expression of voltage-gated potassium Kv1.3 channels is increased in activated microglia, with non-selective blockade reported to attenuate microglial-mediated neuroinflammation. In this study, we evaluated the impact of a potent and selective peptidic blocker of Kv1.3 channels, HsTX1[R14A], on microglial-mediated neuroinflammation in vitro and in vivo. Treatment with both 0.1 and 1 µg/mL lipopolysaccharide (LPS) significantly (p < 0.05) increased Kv1.3 abundance on the surface of BV-2 microglia in association with increased levels of mRNA for tumour necrosis factor-α (TNF-α) and interleukin-6 (IL-6). The increased transcription of TNF-α and IL-6 was significantly attenuated (by 24.9 and 20.2%, respectively) by HsTX1[R14A] (100 nM). The concomitant increase in TNF-α and IL-6 release from BV-2 microglia was significantly attenuated by HsTX1[R14A] by 10.7 and 12.6%, respectively. In LPS-treated primary mouse microglia, the levels of TNF-α and nitric oxide were also attenuated by HsTX1[R14A] (26.1 and 20.4%, respectively). In an LPS-induced mouse model of neuroinflammation, both an immediate and delayed subcutaneous dose of HsTX1[R14A] (2 mg/kg) significantly reduced plasma and brain levels of the pro-inflammatory mediators TNF-α, IL-1β and IL-6, with no impact on the anti-inflammatory IL-10. These results demonstrate that HsTX1[R14A] is a promising therapeutic candidate for the treatment of diseases with a neuroinflammatory component.
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Affiliation(s)
- Joseph A Nicolazzo
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Yijun Pan
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Ilenia Di Stefano
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Kwok H C Choy
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Sanjeevini Babu Reddiar
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Yi Ling Low
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Dorothy C C Wai
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Raymond S Norton
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia; ARC Centre for Fragment-Based Design, Monash University, Parkville, Victoria 3052, Australia
| | - Liang Jin
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
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10
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Sanches K, Wai DCC, Norton RS. Conformational dynamics in peptide toxins: Implications for receptor interactions and molecular design. Toxicon 2021; 201:127-140. [PMID: 34454969 DOI: 10.1016/j.toxicon.2021.08.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Revised: 08/19/2021] [Accepted: 08/23/2021] [Indexed: 10/20/2022]
Abstract
Peptide toxins are potent and often exquisitely selective probes of the structure and function of ion channels and receptors, and are therefore of significant interest to the pharmaceutical and biotech industries as both pharmacological tools and therapeutic leads. The three-dimensional structures of peptide toxins are essential as a basis for understanding their structure-activity relationships and their binding to target receptors, as well as in guiding the design of analogues with modified potency and/or selectivity for key targets. NMR spectroscopy has played a key role in elucidating the structures of peptide toxins and probing their structure-function relationships. In this article, we highlight the additional important contribution of NMR to characterising the dynamics of peptide toxins. We also compare the information available from NMR measurements with that afforded by molecular dynamics simulations. We describe several examples of the importance of dynamics measurements over a range of timescales for understanding the structure-function relationships of peptide toxins and their receptor engagement. Peptide toxins that inhibit the voltage-gated potassium channel KV1.3 with pM affinities display different degrees of conformational flexibility, even though they contain multiple disulfide bonds, and this flexibility can affect the relative orientation of residues that have been shown to be critical for channel binding. Information on the dynamic properties of peptide toxins is important in the design of analogues or mimetics where receptor-bound structures are not available.
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Affiliation(s)
- Karoline Sanches
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, 3052, Australia; ARC Centre for Fragment-Based Design, Monash University, Parkville, Victoria, 3052, Australia
| | - Dorothy C C Wai
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, 3052, Australia
| | - Raymond S Norton
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, 3052, Australia; ARC Centre for Fragment-Based Design, Monash University, Parkville, Victoria, 3052, Australia.
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11
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Reddiar SB, Jin L, Wai DCC, Csoti A, Panyi G, Norton RS, Nicolazzo JA. Lipopolysaccharide influences the plasma and brain pharmacokinetics of subcutaneously-administered HsTX1[R14A], a K V1.3-blocking peptide. Toxicon 2021; 195:29-36. [PMID: 33689790 DOI: 10.1016/j.toxicon.2021.03.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 02/22/2021] [Accepted: 03/03/2021] [Indexed: 12/01/2022]
Abstract
KV1.3 is a voltage-gated potassium channel that is upregulated in neuroinflammatory conditions, such as Alzheimer's disease and Parkinson's disease. HsTX1[R14A] is a potent and selective peptide blocker of KV1.3 with the potential to block microglial KV1.3, but its brain uptake is expected to be limited owing to the restrictive nature of the blood-brain barrier. To assess its peripheral and brain exposure, a LC-MS/MS assay was developed to quantify HsTX1[R14A] concentrations in mouse plasma and brain homogenate that was reliable and reproducible in the range of 6.7-66.7 nM (r2 = 0.9765) and 15-150 pmol/g (r2 = 0.9984), respectively. To assess if neuroinflammation affected HsTX1[R14A] disposition, C57BL/6 mice were administered HsTX1[R14A] subcutaneously (2 mg/kg) 24 h after an intraperitoneal dose of Escherichia coli lipopolysaccharide (LPS), which is commonly used to induce neuroinflammation; brain and plasma concentrations of HsTX1[R14A] were then quantified over 120 min. LPS treatment significantly retarded the decline in HsTX1[R14A] plasma concentrations, presumably as a result of reducing renal clearance, and led to substantial brain uptake of HsTX1[R14A], presumably through disruption of brain inter-endothelial tight junctions. This study suggests that HsTX1[R14A] may reach microglia in sufficient concentrations to block KV1.3 in neuroinflammatory conditions, and therefore has the potential to reduce neurodegenerative diseases.
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Affiliation(s)
- Sanjeevini Babu Reddiar
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia
| | - Liang Jin
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia
| | - Dorothy C C Wai
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia
| | - Agota Csoti
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, Hungary
| | - Gyorgy Panyi
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, Hungary
| | - Raymond S Norton
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia; ARC Centre for Fragment-Based Design, Monash University, Parkville, Victoria, Australia
| | - Joseph A Nicolazzo
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia.
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12
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Krishnarjuna B, Sunanda P, Villegas-Moreno J, Csoti A, A V Morales R, Wai DCC, Panyi G, Prentis P, Norton RS. A disulfide-stabilised helical hairpin fold in acrorhagin I: An emerging structural motif in peptide toxins. J Struct Biol 2020; 213:107692. [PMID: 33387653 DOI: 10.1016/j.jsb.2020.107692] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 12/14/2020] [Accepted: 12/24/2020] [Indexed: 12/22/2022]
Abstract
Acrorhagin I (U-AITX-Aeq5a) is a disulfide-rich peptide identified in the aggressive organs (acrorhagi) of the sea anemone Actinia equina. Previous studies (Toxicon 2005, 46:768-74) found that the peptide is toxic in crabs, although the structural and functional properties of acrorhagin I have not been reported. In this work, an Escherichia coli (BL21 strain) expression system was established for the preparation of 13C,15N-labelled acrorhagin I, and the solution structure was determined using NMR spectroscopy. Structurally, acrorhagin I is similar to B-IV toxin from the marine worm Cerebratulus lacteus (PDB id 1VIB), with a well-defined helical hairpin structure stabilised by four intramolecular disulfide bonds. The recombinant peptide was tested in patch-clamp electrophysiology assays against voltage-gated potassium and sodium channels, and in bacterial and fungal growth inhibitory assays and haemolytic assays. Acrorhagin I was not active against any of the ion channels tested and showed no activity in functional assays, indicating that this peptide may possess a different biological function. Metal ion interaction studies using NMR spectroscopy showed that acrorhagin I bound zinc and nickel, suggesting that its function might be modulated by metal ions or that it may be involved in regulating metal ion levels and their transport. The similarity between the structure of acrorhagin I and that of B-IV toxin from a marine worm suggests that this fold may prove to be a recurring motif in disulfide-rich peptides from marine organisms.
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Affiliation(s)
- Bankala Krishnarjuna
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
| | - Punnepalli Sunanda
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
| | - Jessica Villegas-Moreno
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia; Centro de Investigaciones Químicas, Universidad Autónoma del Estado de Morelos, Cuernavaca, Mexico
| | - Agota Csoti
- Department of Biophysics and Cell Biology, University of Debrecen, 4032 Debrecen, Hungary; MTA-DE-NAP B Ion Channel Structure-Function Research Group, RCMM, University of Debrecen, 4032 Debrecen, Hungary
| | - Rodrigo A V Morales
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
| | - Dorothy C C Wai
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
| | - Gyorgy Panyi
- Department of Biophysics and Cell Biology, University of Debrecen, 4032 Debrecen, Hungary; MTA-DE-NAP B Ion Channel Structure-Function Research Group, RCMM, University of Debrecen, 4032 Debrecen, Hungary
| | - Peter Prentis
- School of Earth, Environmental and Biological Sciences, Science and Engineering Faculty, Queensland University of Technology, Brisbane, Australia; Institute for Future Environments, Queensland University of Technology, Brisbane, Australia
| | - Raymond S Norton
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia; ARC Centre for Fragment-Based Design, Monash University, Parkville, Victoria 3052, Australia.
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13
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Tajti G, Wai DCC, Panyi G, Norton RS. The voltage-gated potassium channel K V1.3 as a therapeutic target for venom-derived peptides. Biochem Pharmacol 2020; 181:114146. [PMID: 32653588 DOI: 10.1016/j.bcp.2020.114146] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 07/05/2020] [Accepted: 07/07/2020] [Indexed: 02/07/2023]
Abstract
The voltage-gated potassium channel KV1.3 is a well-established therapeutic target for a range of autoimmune diseases, in addition to being the site of action of many venom-derived peptides. Numerous studies have documented the efficacy of venom peptides that target KV1.3, in particular from sea anemones and scorpions, in animal models of autoimmune diseases such as rheumatoid arthritis, psoriasis and multiple sclerosis. Moreover, an analogue of the sea anemone peptide ShK (known as dalazatide) has successfully completed Phase 1 clinical trials in mild-to-moderate plaque psoriasis. In this article we consider other potential therapeutic applications of inhibitors of KV1.3, including in inflammatory bowel disease and neuroinflammatory conditions such as Alzheimer's and Parkinson's diseases, as well as fibrotic diseases. We also summarise strategies for facilitating the entry of peptides to the central nervous system, given that this will be a pre-requisite for the treatment of most neuroinflammatory diseases. Venom-derived peptides that have been reported recently to target KV1.3 are also described. The increasing number of autoimmune and other conditions in which KV1.3 is upregulated and is therefore a potential therapeutic target, combined with the fact that many venom-derived peptides are potent inhibitors of KV1.3, suggests that venoms are likely to continue to serve as a rich source of new pharmacological tools and therapeutic leads targeting this channel.
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Affiliation(s)
- Gabor Tajti
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
| | - Dorothy C C Wai
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
| | - Gyorgy Panyi
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary.
| | - Raymond S Norton
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia; ARC Centre for Fragment-Based Design, Monash University, Parkville, VIC 3052, Australia.
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14
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Iwakawa N, Baxter NJ, Wai DCC, Fowler NJ, Morales RAV, Sugase K, Norton RS, Williamson MP. Conformational exchange in the potassium channel blocker ShK. Sci Rep 2019; 9:19307. [PMID: 31848433 PMCID: PMC6917819 DOI: 10.1038/s41598-019-55806-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2019] [Accepted: 11/21/2019] [Indexed: 11/25/2022] Open
Abstract
ShK is a 35-residue disulfide-linked polypeptide produced by the sea anemone Stichodactyla helianthus, which blocks the potassium channels Kv1.1 and Kv1.3 with pM affinity. An analogue of ShK has been developed that blocks Kv1.3 > 100 times more potently than Kv1.1, and has completed Phase 1b clinical trials for the treatment of autoimmune diseases such as psoriasis and rheumatoid arthritis. Previous studies have indicated that ShK undergoes a conformational exchange that is critical to its function, but this has proved difficult to characterise. Here, we have used high hydrostatic pressure as a tool to increase the population of the alternative state, which is likely to resemble the active form that binds to the Kv1.3 channel. By following changes in chemical shift with pressure, we have derived the chemical shift values of the low- and high-pressure states, and thus characterised the locations of structural changes. The main difference is in the conformation of the Cys17-Cys32 disulfide, which is likely to affect the positions of the critical Lys22-Tyr23 pair by twisting the 21–24 helix and increasing the solvent exposure of the Lys22 sidechain, as indicated by molecular dynamics simulations.
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Affiliation(s)
- Naoto Iwakawa
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Kyoto-Daigaku Katsura, Nishikyo-Ku, Kyoto, 615-8510, Japan.,Department of Molecular Biology and Biotechnology, University of Sheffield, Western Bank, Sheffield, S10 2TN, UK
| | - Nicola J Baxter
- Department of Molecular Biology and Biotechnology, University of Sheffield, Western Bank, Sheffield, S10 2TN, UK
| | - Dorothy C C Wai
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, 3052, Australia
| | - Nicholas J Fowler
- Department of Molecular Biology and Biotechnology, University of Sheffield, Western Bank, Sheffield, S10 2TN, UK
| | - Rodrigo A V Morales
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, 3052, Australia.,CSL Limited (Bio21), 30 Flemington Road, Parkville, Victoria, 3010, Australia
| | - Kenji Sugase
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Kyoto-Daigaku Katsura, Nishikyo-Ku, Kyoto, 615-8510, Japan
| | - Raymond S Norton
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, 3052, Australia. .,ARC Centre for Fragment-Based Design, Monash University, Parkville, Victoria, 3052, Australia.
| | - Mike P Williamson
- Department of Molecular Biology and Biotechnology, University of Sheffield, Western Bank, Sheffield, S10 2TN, UK.
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15
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Wai DCC, Szyszka TN, Campbell AE, Kwong C, Wilkinson-White LE, Silva APG, Low JKK, Kwan AH, Gamsjaeger R, Chalmers JD, Patrick WM, Lu B, Vakoc CR, Blobel GA, Mackay JP. The BRD3 ET domain recognizes a short peptide motif through a mechanism that is conserved across chromatin remodelers and transcriptional regulators. J Biol Chem 2018; 293:7160-7175. [PMID: 29567837 DOI: 10.1074/jbc.ra117.000678] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 02/08/2018] [Indexed: 12/31/2022] Open
Abstract
Members of the bromodomain and extra-terminal domain (BET) family of proteins (bromodomain-containing (BRD) 2, 3, 4, and T) are widely expressed and highly conserved regulators of gene expression in eukaryotes. These proteins have been intimately linked to human disease, and more than a dozen clinical trials are currently underway to test BET-protein inhibitors as modulators of cancer. However, although it is clear that these proteins use their bromodomains to bind both histones and transcription factors bearing acetylated lysine residues, the molecular mechanisms by which BET family proteins regulate gene expression are not well defined. In particular, the functions of the other domains such as the ET domain have been less extensively studied. Here, we examine the properties of the ET domain of BRD3 as a protein/protein interaction module. Using a combination of pulldown and biophysical assays, we demonstrate that BRD3 binds to a range of chromatin-remodeling complexes, including the NuRD, BAF, and INO80 complexes, via a short linear "KIKL" motif in one of the complex subunits. NMR-based structural analysis revealed that, surprisingly, this mode of interaction is shared by the AF9 and ENL transcriptional coregulators that contain an acetyl-lysine-binding YEATS domain and regulate transcriptional elongation. This observation establishes a functional commonality between these two families of cancer-related transcriptional regulators. In summary, our data provide insight into the mechanisms by which BET family proteins might link chromatin acetylation to transcriptional outcomes and uncover an unexpected functional similarity between BET and YEATS family proteins.
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Affiliation(s)
- Dorothy C C Wai
- School of Life and Environmental Sciences, University of Sydney New South Wales 2006, Australia
| | - Taylor N Szyszka
- School of Life and Environmental Sciences, University of Sydney New South Wales 2006, Australia
| | - Amy E Campbell
- Division of Hematology, Children's Hospital of Philadelphia, and the Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Cherry Kwong
- School of Life and Environmental Sciences, University of Sydney New South Wales 2006, Australia
| | - Lorna E Wilkinson-White
- School of Life and Environmental Sciences, University of Sydney New South Wales 2006, Australia
| | - Ana P G Silva
- School of Life and Environmental Sciences, University of Sydney New South Wales 2006, Australia
| | - Jason K K Low
- School of Life and Environmental Sciences, University of Sydney New South Wales 2006, Australia
| | - Ann H Kwan
- School of Life and Environmental Sciences, University of Sydney New South Wales 2006, Australia
| | - Roland Gamsjaeger
- School of Life and Environmental Sciences, University of Sydney New South Wales 2006, Australia
| | - James D Chalmers
- Department of Biochemistry, University of Otago, Dunedin 9016, New Zealand
| | - Wayne M Patrick
- Department of Biochemistry, University of Otago, Dunedin 9016, New Zealand
| | - Bin Lu
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724
| | | | - Gerd A Blobel
- Division of Hematology, Children's Hospital of Philadelphia, and the Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Joel P Mackay
- School of Life and Environmental Sciences, University of Sydney New South Wales 2006, Australia.
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16
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Wai DCC, Shihab M, Low JKK, Mackay JP. The zinc fingers of YY1 bind single-stranded RNA with low sequence specificity. Nucleic Acids Res 2016; 44:9153-9165. [PMID: 27369384 PMCID: PMC5100589 DOI: 10.1093/nar/gkw590] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Accepted: 06/16/2016] [Indexed: 12/22/2022] Open
Abstract
Classical zinc fingers (ZFs) are traditionally considered to act as sequence-specific DNA-binding domains. More recently, classical ZFs have been recognised as potential RNA-binding modules, raising the intriguing possibility that classical-ZF transcription factors are involved in post-transcriptional gene regulation via direct RNA binding. To date, however, only one classical ZF-RNA complex, that involving TFIIIA, has been structurally characterised. Yin Yang-1 (YY1) is a multi-functional transcription factor involved in many regulatory processes, and binds DNA via four classical ZFs. Recent evidence suggests that YY1 also interacts with RNA, but the molecular nature of the interaction remains unknown. In the present work, we directly assess the ability of YY1 to bind RNA using in vitro assays. Systematic Evolution of Ligands by EXponential enrichment (SELEX) was used to identify preferred RNA sequences bound by the YY1 ZFs from a randomised library over multiple rounds of selection. However, a strong motif was not consistently recovered, suggesting that the RNA sequence selectivity of these domains is modest. YY1 ZF residues involved in binding to single-stranded RNA were identified by NMR spectroscopy and found to be largely distinct from the set of residues involved in DNA binding, suggesting that interactions between YY1 and ssRNA constitute a separate mode of nucleic acid binding. Our data are consistent with recent reports that YY1 can bind to RNA in a low-specificity, yet physiologically relevant manner.
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Affiliation(s)
- Dorothy C C Wai
- School of Life and Environmental Sciences, University of Sydney, NSW 2006, Australia
| | - Manar Shihab
- School of Life and Environmental Sciences, University of Sydney, NSW 2006, Australia
| | - Jason K K Low
- School of Life and Environmental Sciences, University of Sydney, NSW 2006, Australia
| | - Joel P Mackay
- School of Life and Environmental Sciences, University of Sydney, NSW 2006, Australia
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