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Peigneur S, Tibery D, Tytgat J. The Helix Ring Peptide U 11 from the Venom of the Ant, Tetramorium bicarinatum, Acts as a Putative Pore-Forming Toxin. MEMBRANES 2024; 14:114. [PMID: 38786948 PMCID: PMC11123039 DOI: 10.3390/membranes14050114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2024] [Revised: 04/26/2024] [Accepted: 05/09/2024] [Indexed: 05/25/2024]
Abstract
An insect neuroactive helix ring peptide called U11-MYRTX-Tb1a (abbreviated as U11) from the venom of the ant, Tetramorium bicarinatum. U11 is a 34-amino-acid peptide that is claimed to be one of the most paralytic peptides ever reported from ant venoms acting against blowflies and honeybees. The peptide features a compact triangular ring helix structure stabilized by a single disulfide bond, which is a unique three-dimensional scaffold among animal venoms. Pharmacological assays using Drosophila S2 cells have demonstrated that U11 is not cytotoxic but instead suggest that it may modulate potassium channels via the presence of a functional dyad. In our work described here, we have tested this hypothesis by investigating the action of synthetically made U11 on a wide array of voltage-gated K and Na channels since it is well known that these channels play a crucial role in the phenomenon of paralysis. Using the Xenopus laevis oocyte heterologous expression system and voltage clamp, our results have not shown any modulatory effect of 1 μM U11 on the activity of Kv1.1, Kv1.3, Kv1.4, Kv1.5, Shaker IR, Kv4.2, Kv7.1, Kv10.1, Kv11.1 and KQT1, nor on DmNav and BgNav. Instead, 10 μM U11 caused a quick and irreversible cytolytic effect, identical to the cytotoxic effect caused by Apis mellifera venom, which indicates that U11 can act as a pore-forming peptide. Interestingly, the paralytic dose (PD50) on blowflies and honeybees corresponds with the concentration at which U11 displays clear pore-forming activity. In conclusion, our results indicate that the insecticidal and paralytic effects caused by U11 may be explained by the putative pore formation of the peptide.
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Affiliation(s)
- Steve Peigneur
- Toxicology and Pharmacology, University of Leuven (KU Leuven), P.O. Box 922, Herestraat 49, 3000 Leuven, Belgium; (S.P.); (D.T.)
| | - Diogo Tibery
- Toxicology and Pharmacology, University of Leuven (KU Leuven), P.O. Box 922, Herestraat 49, 3000 Leuven, Belgium; (S.P.); (D.T.)
- Laboratory of Neuropharmacology, Department of Physiological Sciences, University of Brasília, Distrito Federal, Brasília 70910-900, Brazil
| | - Jan Tytgat
- Toxicology and Pharmacology, University of Leuven (KU Leuven), P.O. Box 922, Herestraat 49, 3000 Leuven, Belgium; (S.P.); (D.T.)
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Kim YJ, Jo Y, Lee SE, Kim J, Choi JP, Lee N, Won H, Woo DH, Yum S. Synthetic ShK-like Peptide from the Jellyfish Nemopilema nomurai Has Human Voltage-Gated Potassium-Channel-Blocking Activity. Mar Drugs 2024; 22:217. [PMID: 38786608 PMCID: PMC11122761 DOI: 10.3390/md22050217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2024] [Revised: 05/08/2024] [Accepted: 05/10/2024] [Indexed: 05/25/2024] Open
Abstract
We identified a new human voltage-gated potassium channel blocker, NnK-1, in the jellyfish Nemopilema nomurai based on its genomic information. The gene sequence encoding NnK-1 contains 5408 base pairs, with five introns and six exons. The coding sequence of the NnK-1 precursor is 894 nucleotides long and encodes 297 amino acids containing five presumptive ShK-like peptides. An electrophysiological assay demonstrated that the fifth peptide, NnK-1, which was chemically synthesized, is an effective blocker of hKv1.3, hKv1.4, and hKv1.5. Multiple-sequence alignment with cnidarian Shk-like peptides, which have Kv1.3-blocking activity, revealed that three residues (3Asp, 25Lys, and 34Thr) of NnK-1, together with six cysteine residues, were conserved. Therefore, we hypothesized that these three residues are crucial for the binding of the toxin to voltage-gated potassium channels. This notion was confirmed by an electrophysiological assay with a synthetic peptide (NnK-1 mu) where these three peptides were substituted with 3Glu, 25Arg, and 34Met. In conclusion, we successfully identified and characterized a new voltage-gated potassium channel blocker in jellyfish that interacts with three different voltage-gated potassium channels. A peptide that interacts with multiple voltage-gated potassium channels has many therapeutic applications in various physiological and pathophysiological contexts.
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Affiliation(s)
- Ye-Ji Kim
- Department of Advanced Toxicology Research, Korea Institute of Toxicology (KIT), Daejeon 34114, Republic of Korea;
- Human and Environmental Toxicology, University of Science and Technology, Daejeon 34114, Republic of Korea
| | - Yejin Jo
- Ecological Risk Research Division, Korea Institute of Ocean Science and Technology (KIOST), Geoje 53201, Republic of Korea; (Y.J.); (N.L.); (H.W.)
| | - Seung Eun Lee
- Research Animal Resource Center, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea;
| | - Jungeun Kim
- Personal Genomics Institute (PGI), Genome Research Foundation (GRF), Cheongju 28160, Republic of Korea; (J.K.); (J.-P.C.)
| | - Jae-Pil Choi
- Personal Genomics Institute (PGI), Genome Research Foundation (GRF), Cheongju 28160, Republic of Korea; (J.K.); (J.-P.C.)
| | - Nayoung Lee
- Ecological Risk Research Division, Korea Institute of Ocean Science and Technology (KIOST), Geoje 53201, Republic of Korea; (Y.J.); (N.L.); (H.W.)
| | - Hyokyoung Won
- Ecological Risk Research Division, Korea Institute of Ocean Science and Technology (KIOST), Geoje 53201, Republic of Korea; (Y.J.); (N.L.); (H.W.)
| | - Dong Ho Woo
- Department of Advanced Toxicology Research, Korea Institute of Toxicology (KIT), Daejeon 34114, Republic of Korea;
- Human and Environmental Toxicology, University of Science and Technology, Daejeon 34114, Republic of Korea
| | - Seungshic Yum
- Ecological Risk Research Division, Korea Institute of Ocean Science and Technology (KIOST), Geoje 53201, Republic of Korea; (Y.J.); (N.L.); (H.W.)
- KIOST School, University of Science and Technology, Geoje 53201, Republic of Korea
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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] [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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Krishnarjuna B, Sharma G, Im SC, Auchus R, Anantharamaiah GM, Ramamoorthy A. Characterization of nanodisc-forming peptides for membrane protein studies. J Colloid Interface Sci 2024; 653:1402-1414. [PMID: 37801850 PMCID: PMC10864042 DOI: 10.1016/j.jcis.2023.09.162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 09/11/2023] [Accepted: 09/27/2023] [Indexed: 10/08/2023]
Abstract
Lipid-bilayer nanodiscs provide a stable, native-like membrane environment for the functional and structural studies of membrane proteins and other membrane-binding molecules. Peptide-based nanodiscs having unique properties are developed for membrane protein studies and other biological applications. While the self-assembly process rendering the formation of peptide-nanodiscs is attractive, it is important to understand the stability and suitability of these nanodisc systems for membrane protein studies. In this study, we investigated the nanodiscs formation by the anti-inflammatory and tumor-suppressing peptide AEM28. AEM28 is a chimeric peptide containing a cationic-rich heparan sulfate proteoglycan- (HSPG)-binding domain from human apolipoprotein E (hapoE) (141-150) followed by the 18A peptide's amino acid sequence. AEM28-based nanodiscs made with different types of lipids were characterized using various biophysical techniques and compared with the nanodiscs formed using 2F or 4F peptides. Variable temperature dynamic light-scattering and 31P NMR experiments indicated the fusion and size heterogeneity of nanodiscs at high temperatures. The suitability of AEM28 and Ac-18A-NH2- (2F-) based nanodiscs for studying membrane proteins is demonstrated by reconstituting and characterizing a drug-metabolizing enzyme, cytochrome-P450 (CYP450), or the redox complex CYP450-CYP450 reductase. AEM28 and 2F were also tested for their efficacies in solubilizing E. coli membranes to understand the possibility of using them for detergent-free membrane protein isolation. Our experimental results suggest that AEM28 nanodiscs are suitable for studying membrane proteins with a net positive charge, whereas 2F-based nanodiscs are compatible with any membrane proteins and their complexes irrespective of their charge. Furthermore, both peptides solubilized E. coli cell membranes, indicating their use in membrane protein isolation and other applications related to membrane solubilization.
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Affiliation(s)
- Bankala Krishnarjuna
- Biophysics Program, Department of Chemistry, Biomedical Engineering, Macromolecular Science and Engineering, University of Michigan, Arbor, MI 48109, USA
| | - Gaurav Sharma
- Biophysics Program, Department of Chemistry, Biomedical Engineering, Macromolecular Science and Engineering, University of Michigan, Arbor, MI 48109, USA
| | - Sang-Choul Im
- Department of Pharmacology and Internal Medicine, Division of Metabolism, Endocrinology, & Diabetes, University of Michigan, Ann Arbor, MI 48109, USA
| | - Richard Auchus
- Department of Pharmacology and Internal Medicine, Division of Metabolism, Endocrinology, & Diabetes, University of Michigan, Ann Arbor, MI 48109, USA
| | - G M Anantharamaiah
- Department of Medicine, University of Alabama at Birmingham Medical Center, Birmingham, AL 35294, USA
| | - Ayyalusamy Ramamoorthy
- Biophysics Program, Department of Chemistry, Biomedical Engineering, Macromolecular Science and Engineering, University of Michigan, Arbor, MI 48109, USA; National High Magnetic Field Laboratory, Department of Chemical and Biomedical Engineering, Tallahassee, FL 32310, USA.
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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] [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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Krishnarjuna B, Sunanda P, Seow J, Tae HS, Robinson SD, Belgi A, Robinson AJ, Safavi-Hemami H, Adams DJ, Norton RS. Characterisation of Elevenin-Vc1 from the Venom of Conus victoriae: A Structural Analogue of α-Conotoxins. Mar Drugs 2023; 21:md21020081. [PMID: 36827123 PMCID: PMC9963005 DOI: 10.3390/md21020081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2022] [Revised: 01/12/2023] [Accepted: 01/23/2023] [Indexed: 01/27/2023] Open
Abstract
Elevenins are peptides found in a range of organisms, including arthropods, annelids, nematodes, and molluscs. They consist of 17 to 19 amino acid residues with a single conserved disulfide bond. The subject of this study, elevenin-Vc1, was first identified in the venom of the cone snail Conus victoriae (Gen. Comp. Endocrinol. 2017, 244, 11-18). Although numerous elevenin sequences have been reported, their physiological function is unclear, and no structural information is available. Upon intracranial injection in mice, elevenin-Vc1 induced hyperactivity at doses of 5 or 10 nmol. The structure of elevenin-Vc1, determined using nuclear magnetic resonance spectroscopy, consists of a short helix and a bend region stabilised by the single disulfide bond. The elevenin-Vc1 structural fold is similar to that of α-conotoxins such as α-RgIA and α-ImI, which are also found in the venoms of cone snails and are antagonists at specific subtypes of nicotinic acetylcholine receptors (nAChRs). In an attempt to mimic the functional motif, Asp-Pro-Arg, of α-RgIA and α-ImI, we synthesised an analogue, designated elevenin-Vc1-DPR. However, neither elevenin-Vc1 nor the analogue was active at six different human nAChR subtypes (α1β1εδ, α3β2, α3β4, α4β2, α7, and α9α10) at 1 µM concentrations.
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Affiliation(s)
- Bankala Krishnarjuna
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC 3052, Australia
| | - Punnepalli Sunanda
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC 3052, Australia
| | - Jeffrey Seow
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC 3052, Australia
| | - Han-Shen Tae
- Illawarra Health and Medical Research Institute (IHMRI), University of Wollongong, Wollongong, NSW 2522, Australia
| | - Samuel D. Robinson
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC 3052, Australia
| | - Alessia Belgi
- School of Chemistry, Monash University, Clayton, VIC 3800, Australia
| | | | | | - David J. Adams
- Illawarra Health and Medical Research Institute (IHMRI), University of Wollongong, Wollongong, NSW 2522, Australia
| | - Raymond S. Norton
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC 3052, Australia
- Correspondence: ; Tel.: +61-3-9903-9167
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Krishnarjuna B, Ramamoorthy A. Detergent-Free Isolation of Membrane Proteins and Strategies to Study Them in a Near-Native Membrane Environment. Biomolecules 2022; 12:1076. [PMID: 36008970 PMCID: PMC9406181 DOI: 10.3390/biom12081076] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2022] [Revised: 07/31/2022] [Accepted: 08/02/2022] [Indexed: 02/06/2023] Open
Abstract
Atomic-resolution structural studies of membrane-associated proteins and peptides in a membrane environment are important to fully understand their biological function and the roles played by them in the pathology of many diseases. However, the complexity of the cell membrane has severely limited the application of commonly used biophysical and biochemical techniques. Recent advancements in NMR spectroscopy and cryoEM approaches and the development of novel membrane mimetics have overcome some of the major challenges in this area. For example, the development of a variety of lipid-nanodiscs has enabled stable reconstitution and structural and functional studies of membrane proteins. In particular, the ability of synthetic amphipathic polymers to isolate membrane proteins directly from the cell membrane, along with the associated membrane components such as lipids, without the use of a detergent, has opened new avenues to study the structure and function of membrane proteins using a variety of biophysical and biological approaches. This review article is focused on covering the various polymers and approaches developed and their applications for the functional reconstitution and structural investigation of membrane proteins. The unique advantages and limitations of the use of synthetic polymers are also discussed.
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Affiliation(s)
- Bankala Krishnarjuna
- Department of Chemistry and Biophysics, Biomedical Engineering, Macromolecular Science and Engineering, Michigan Neuroscience Institute, The University of Michigan, Ann Arbor, MI 48109-1055, USA
| | - Ayyalusamy Ramamoorthy
- Department of Chemistry and Biophysics, Biomedical Engineering, Macromolecular Science and Engineering, Michigan Neuroscience Institute, The University of Michigan, Ann Arbor, MI 48109-1055, USA
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8
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Menezes C, Thakur NL. Sea anemone venom: Ecological interactions and bioactive potential. Toxicon 2022; 208:31-46. [DOI: 10.1016/j.toxicon.2022.01.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 01/05/2022] [Accepted: 01/06/2022] [Indexed: 10/19/2022]
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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] [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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10
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Krishnarjuna B, Ivanova MI, Ramamoorthy A. Aggregation and the Intrinsic Structural Disorder of Dipeptide Repeat Peptides of C9orf72-Related Amyotrophic Lateral Sclerosis and Frontotemporal Dementia Characterized by NMR. J Phys Chem B 2021; 125:12446-12456. [PMID: 34751579 DOI: 10.1021/acs.jpcb.1c08149] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Dipeptide repeats (DPRs) are known to play important roles in C9ORF72-related amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Studies on DPRs have reported on the kinetics of aggregation, toxicity, and low-resolution morphology of the aggregates of these peptides. While the dipeptide hexa-repeats of Gly-Pro [(GP)6] have been shown to be nonaggregating, Gly-Ala [(GA)6] and Gly-Arg [(GR)6] exhibited the formation of neurotoxic aggregates. However, structural studies of these DPRs have been elusive. In this study, we explored the feasibility of a high-resolution monitoring of a real-time aggregation of these peptides in a solution by using NMR experiments. Although (GP)6 is disordered and nonaggregating, the existence of cis and trans conformations was observed from NMR spectra. It was remarkable that the (GR)6 exhibited the formation of multiple conformations, whereas the hydrophobic and low-soluble (GA)6 aggregated fast in a temperature-dependent manner. These results demonstrate the feasibility of monitoring the minor conformational changes from highly disordered peptides, aggregation kinetics, and the formation of small molecular weight aggregates by solution NMR experiments. The ability to detect cis and trans local isomerizations in (GP)6 is noteworthy and could be valuable to study intrinsically disordered proteins/peptides by NMR. The early detection of minor conformational changes could be valuable in better understanding the mechanistic insights into the formation of toxic intermediates and the development of approaches to inhibit them and, potentially, aid in the development of compounds to treat the devastating C9ORF72-related ALS and FTD diseases.
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Affiliation(s)
| | - Magdalena I Ivanova
- Department of Neurology, University of Michigan, Ann Arbor, Michigan 48109 United States
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11
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Trim CM, Byrne LJ, Trim SA. Utilisation of compounds from venoms in drug discovery. PROGRESS IN MEDICINAL CHEMISTRY 2021; 60:1-66. [PMID: 34147202 DOI: 10.1016/bs.pmch.2021.01.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Difficult drug targets are becoming the normal course of business in drug discovery, sometimes due to large interacting surfaces or only small differences in selectivity regions. For these, a different approach is merited: compounds lying somewhere between the small molecule and the large antibody in terms of many properties including stability, biodistribution and pharmacokinetics. Venoms have evolved over millions of years to be complex mixtures of stable molecules derived from other somatic molecules, the stability comes from the pressure to be ready for delivery at a moment's notice. Snakes, spiders, scorpions, jellyfish, wasps, fish and even mammals have evolved independent venom systems with complex mixtures in their chemical arsenal. These venom-derived molecules have been proven to be useful tools, such as for the development of antihypotensive angiotensin converting enzyme (ACE) inhibitors and have also made successful drugs such as Byetta® (Exenatide), Integrilin® (Eptifibatide) and Echistatin. Only a small percentage of the available chemical space from venoms has been investigated so far and this is growing. In a new era of biological therapeutics, venom peptides present opportunities for larger target engagement surface with greater stability than antibodies or human peptides. There are challenges for oral absorption and target engagement, but there are venom structures that overcome these and thus provide substrate for engineering novel molecules that combine all desired properties. Venom researchers are characterising new venoms, species, and functions all the time, these provide great substrate for solving the challenges presented by today's difficult targets.
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Affiliation(s)
- Carol M Trim
- Faculty of Science, Engineering and Social Sciences, Natural and Applied Sciences, School of Psychology and Life Sciences, Canterbury Christ Church University, Canterbury, Kent, United Kingdom
| | - Lee J Byrne
- Faculty of Science, Engineering and Social Sciences, Natural and Applied Sciences, School of Psychology and Life Sciences, Canterbury Christ Church University, Canterbury, Kent, United Kingdom
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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] [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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Ong ST, Bajaj S, Tanner MR, Chang SC, Krishnarjuna B, Ng XR, Morales RAV, Chen MW, Luo D, Patel D, Yasmin S, Ng JJH, Zhuang Z, Nguyen HM, El Sahili A, Lescar J, Patil R, Charman SA, Robins EG, Goggi JL, Tan PW, Sadasivam P, Ramasamy B, Hartimath SV, Dhawan V, Bednenko J, Colussi P, Wulff H, Pennington MW, Kuyucak S, Norton RS, Beeton C, Chandy KG. Modulation of Lymphocyte Potassium Channel K V1.3 by Membrane-Penetrating, Joint-Targeting Immunomodulatory Plant Defensin. ACS Pharmacol Transl Sci 2020; 3:720-736. [PMID: 32832873 DOI: 10.1021/acsptsci.0c00035] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Indexed: 12/23/2022]
Abstract
We describe a cysteine-rich, membrane-penetrating, joint-targeting, and remarkably stable peptide, EgK5, that modulates voltage-gated KV1.3 potassium channels in T lymphocytes by a distinctive mechanism. EgK5 enters plasma membranes and binds to KV1.3, causing current run-down by a phosphatidylinositol 4,5-bisphosphate-dependent mechanism. EgK5 exhibits selectivity for KV1.3 over other channels, receptors, transporters, and enzymes. EgK5 suppresses antigen-triggered proliferation of effector memory T cells, a subset enriched among pathogenic autoreactive T cells in autoimmune disease. PET-CT imaging with 18F-labeled EgK5 shows accumulation of the peptide in large and small joints of rodents. In keeping with its arthrotropism, EgK5 treats disease in a rat model of rheumatoid arthritis. It was also effective in treating disease in a rat model of atopic dermatitis. No signs of toxicity are observed at 10-100 times the in vivo dose. EgK5 shows promise for clinical development as a therapeutic for autoimmune diseases.
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Affiliation(s)
- Seow Theng Ong
- Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, Experimental Medicine Building, 59 Nanyang Drive, Singapore 636921
| | - Saumya Bajaj
- Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, Experimental Medicine Building, 59 Nanyang Drive, Singapore 636921
| | - Mark R Tanner
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, One Baylor Plaza, Houston, Texas 77030, United States
| | - Shih Chieh Chang
- Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, Experimental Medicine Building, 59 Nanyang Drive, Singapore 636921
| | - Bankala Krishnarjuna
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Xuan Rui Ng
- Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, Experimental Medicine Building, 59 Nanyang Drive, Singapore 636921
| | - Rodrigo A V Morales
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Ming Wei Chen
- Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, Experimental Medicine Building, 59 Nanyang Drive, Singapore 636921
| | - Dahai Luo
- Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, Experimental Medicine Building, 59 Nanyang Drive, Singapore 636921
| | - Dharmeshkumar Patel
- School of Physics, University of Sydney, Sydney, New South Wales 2006, Australia
| | - Sabina Yasmin
- School of Physics, University of Sydney, Sydney, New South Wales 2006, Australia
| | - Jeremy Jun Heng Ng
- Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, Experimental Medicine Building, 59 Nanyang Drive, Singapore 636921
| | - Zhong Zhuang
- Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, Experimental Medicine Building, 59 Nanyang Drive, Singapore 636921
| | - Hai M Nguyen
- Department of Pharmacology, University of California, Davis, California 95616, United States
| | - Abbas El Sahili
- School of Biological Sciences, Nanyang Institute of Structural Biology, Experimental Medicine building, Singapore 636921
| | - Julien Lescar
- School of Biological Sciences, Nanyang Institute of Structural Biology, Experimental Medicine building, Singapore 636921
| | - Rahul Patil
- Centre for Drug Candidate Optimisation, Monash University, Parkville, Victoria 3052, Australia
| | - Susan A Charman
- Centre for Drug Candidate Optimisation, Monash University, Parkville, Victoria 3052, Australia
| | - Edward G Robins
- Singapore Bioimaging Consortium, Agency for Science, Technology and Research (A Star), Singapore 138667.,Singapore Bioimaging Consortium, NUS Clinical Imaging Research Centre (CIRC), Centre for Life Sciences, Singapore 117599
| | - Julian L Goggi
- Singapore Bioimaging Consortium, Agency for Science, Technology and Research (A Star), Singapore 138667
| | - Peng Wen Tan
- Singapore Bioimaging Consortium, Agency for Science, Technology and Research (A Star), Singapore 138667
| | - Pragalath Sadasivam
- Singapore Bioimaging Consortium, Agency for Science, Technology and Research (A Star), Singapore 138667
| | - Boominathan Ramasamy
- Singapore Bioimaging Consortium, Agency for Science, Technology and Research (A Star), Singapore 138667
| | - Siddana V Hartimath
- Singapore Bioimaging Consortium, Agency for Science, Technology and Research (A Star), Singapore 138667
| | - Vikas Dhawan
- Peptides International, Inc., Louisville, Kentucky 40269, United States.,AmbioPharm Inc., North Augusta, South Carolina 29842, United States
| | - Janna Bednenko
- TetraGenetics Inc, Arlington, Massachusetts 02474, United States
| | - Paul Colussi
- TetraGenetics Inc, Arlington, Massachusetts 02474, United States
| | - Heike Wulff
- Department of Pharmacology, University of California, Davis, California 95616, United States
| | - Michael W Pennington
- Peptides International, Inc., Louisville, Kentucky 40269, United States.,AmbioPharm Inc., North Augusta, South Carolina 29842, United States
| | - Serdar Kuyucak
- School of Physics, University of Sydney, Sydney, New South Wales 2006, 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
| | - Christine Beeton
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, One Baylor Plaza, Houston, Texas 77030, United States
| | - K George Chandy
- Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, Experimental Medicine Building, 59 Nanyang Drive, Singapore 636921
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14
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Mitchell ML, Tonkin-Hill GQ, Morales RAV, Purcell AW, Papenfuss AT, Norton RS. Tentacle Transcriptomes of the Speckled Anemone (Actiniaria: Actiniidae: Oulactis sp.): Venom-Related Components and Their Domain Structure. MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2020; 22:207-219. [PMID: 31981004 DOI: 10.1007/s10126-020-09945-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Accepted: 01/02/2020] [Indexed: 06/10/2023]
Abstract
Cnidarians are one of the oldest known animal lineages (ca. 700 million years), with a unique envenomation apparatus to deliver a potent mixture of peptides and proteins. Some peptide toxins from cnidarian venom have proven therapeutic potential. Here, we use a transcriptomic/proteomic strategy to identify sequences with similarity to known venom protein families in the tentacles of the endemic Australian 'speckled anemone' (Oulactis sp.). Illumina RNASeq data were assembled de novo. Annotated sequences in the library were verified by cross-referencing individuals' transcriptomes or protein expression evidence from LC-MS/MS data. Sequences include pore-forming toxins, phospholipases, peptidases, neurotoxins (sodium and potassium channel modulators), cysteine-rich secretory proteins and defensins (antimicrobial peptides). Fewer than 4% of the sequences in the library occurred across the three individuals examined, demonstrating high sequence variability of an individual's arsenal. We searched for actinoporins in Oulactis sp. to assess sequence similarity to the only described toxins (OR-A and -G) for this genus and examined the domain architecture of venom-related peptides and proteins. The novel putative actinoporin of Oulactis sp. has a greater similarity to other species in the Actiniidae family than to O. orientalis. Venom-related sequences have an architecture that occurs in single, repeat or multi-domain combinations of venom-related (e.g. ShK-like) and non-venom (e.g. whey acid protein) domains. This study has produced the first transcriptomes for an endemic Australian sea anemone species and the genus Oulactis, while identifying nearly 400 novel venom-related peptides and proteins for future structural and functional analyses and venom evolution studies.
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Affiliation(s)
- Michela L Mitchell
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, Victoria, 3052, Australia.
- Sciences Department, Museum Victoria, G.P.O. Box 666, Melbourne, Victoria, 3001, Australia.
- Queensland Museum, P.O. Box 3000, South Brisbane, Queensland, 4101, Australia.
- Bioinformatics Division, Walter & Eliza Hall Institute of Research, 1G Royal Parade, Parkville, Victoria, 3052, Australia.
| | - Gerry Q Tonkin-Hill
- Bioinformatics Division, Walter & Eliza Hall Institute of Research, 1G Royal Parade, Parkville, Victoria, 3052, Australia
| | - Rodrigo A V Morales
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, Victoria, 3052, Australia
- CSL Limited, 30 Flemington Road, Parkville, Victoria, 3010, Australia
| | - Anthony W Purcell
- Department of Biochemistry and Molecular Biology and Infection and Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, 3800, Australia
| | - Anthony T Papenfuss
- Bioinformatics Division, Walter & Eliza Hall Institute of Research, 1G Royal Parade, Parkville, Victoria, 3052, Australia
- Peter MacCallum Cancer Centre, Melbourne, Victoria, 3010, Australia
- Department of Medical Biology, University of Melbourne, Melbourne, Victoria, 3010, Australia
- Sir Peter MacCallum Department of Oncology, University of Melbourne, Melbourne, Victoria, 3010, Australia
- School of Mathematics and Statistics, University of Melbourne, Melbourne, Victoria, 3010, 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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15
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Synthesis, folding, structure and activity of a predicted peptide from the sea anemone Oulactis sp. with an ShKT fold. Toxicon 2018; 150:50-59. [DOI: 10.1016/j.toxicon.2018.05.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Revised: 05/08/2018] [Accepted: 05/13/2018] [Indexed: 11/22/2022]
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