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001-es BibID:	BIBFORM083629
035-os BibID:	(WoS)000518872600011 (Scopus)85078049471 (PMID)31870846
Első szerző:	Jin, Jiayi
Cím:	Weaponisation 'on the fly' : convergent recruitment of knottin and defensin peptide scaffolds into the venom of predatory assassin flies / Jiayi Jin, Akello J. Agwa, G. Tibor Szanto, Agota Csóti, Gyorgy Panyi, Christina I. Schroeder, Andrew A. Walker, Glenn F. King
Dátum:	2020
ISSN:	0965-1748
Megjegyzések:	Many arthropod venom peptides have potential as bioinsecticides, drug leads, and pharmacological tools due to their specific neuromodulatory functions. Assassin flies (Asilidae) are a family of predaceous dipterans that produce a unique and complex peptide-rich venom for killing insect prey and deterring predators. However, very little is known about the structure and function of their venom peptides. We therefore used an E. coli periplasmic expression system to express four disulfide-rich peptides that we previously reported to exist in venom of the giant assassin fly Dolopus genitalis. After purification, each recombinant peptide eluted from a C18 column at a position closely matching its natural counterpart, strongly suggesting adoption of the native tertiary fold. Injection of purified recombinant peptides into blowflies (Lucilia cuprina) and crickets (Acheta domestica) revealed that two of the four recombinant peptides, named rDg3b and rDg12, inhibited escape behaviour in a manner that was rapid in onset (<1 min) and reversible. Homonuclear NMR solution structures revealed that rDg3b and rDg12 adopt cystine-stabilised α/ß defensin and inhibitor cystine knot folds, respectively. Although the closest known homologues of rDg3b at the level of primary structure are dipteran antimicrobial peptides such as sapecin and lucifensin, a DALI search showed that the tertiary structure of rDg3b most closely resembles the KV11.1-specific α-potassium channel toxin CnErg1 from venom of the scorpion Centruroides noxius. This is mainly due to the deletion of a large, unstructured loop between the first and second cysteine residues present in Dg3b homologues from non-asiloid, but not existing in asiloid, species. Patch-clamp electrophysiology experiments revealed that rDg3b shifts the voltage-dependence of KV11.1 channel activation to more depolarised potentials, but has no effect on KV1.3, KV2.1, KV10.1, KCa1.1, or the Drosophila Shaker channel. Although rDg12 shares the inhibitor cystine knot structure of many gating modifier toxins, rDg12 did not affect any of these KV channel subtypes. Our results demonstrate that multiple disulfide-rich peptide scaffolds have been convergently recruited into asilid and other animal venoms, and they provide insight into the molecular evolution accompanying their weaponisation.
Tárgyszavak:	Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk Diptera Dolopus genitalis Ion channel K(V)11.1 (hERG) Toxin
Megjelenés:	Insect Biochemistry and Molecular Biology. - 118 (2020), p. 1-12. -
További szerzők:	Agwa, Akello J. Szántó Gábor Tibor (1980-) (vegyész) Csóti Ágota (1989-) (biológus) Panyi György (1966-) (biofizikus) Schroeder, Christina I. Walker, Andrew A. King, Glenn F.
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001-es BibID:	BIBFORM086320
035-os BibID:	(cikkazonosító)113782 (WoS)000527342900009 (Scopus)85077711551
Első szerző:	Luna-Ramirez, Karen
Cím:	Structural basis of the potency and selectivity of Urotoxin, a potent Kv1 blocker from scorpion venom / Karen Luna-Ramirez, Agota Csoti, Jeffrey R. McArthur, Yanni K. Y. Chin, Raveendra Anangi, Rosby del Carmen Najera, Lourival D. Possani, Glenn F. King, Gyorgy Panyi, Haibo Yu, David J. Adams, Rocio K. Finol-Urdaneta
Dátum:	2020
ISSN:	0006-2952
Megjegyzések:	Urotoxin (?-KTx 6), a peptide from venom of the Australian scorpion Urodacus yaschenkoi, is the most potent inhibitor of Kv1.2 described to date (IC = 160 pM). The native peptide also inhibits Kv1.1, Kv1.3 and KCa3.1 with nanomolar affinity but its low abundance in venom precluded further studies of its actions. Here we produced recombinant Urotoxin (rUro) and characterized the molecular determinants of Kv1 channel inhibition. The 3D structure of rUro determined using NMR spectroscopy revealed a canonical cysteine-stabilised ?/? (CS?/?) fold. Functional assessment of rUro using patch-clamp electrophysiology revealed the importance of C-terminal amidation for potency against Kv1.1?1.3 and Kv1.5. Neutralization of the putative pore-blocking K25 residue in rUro by mutation to Ala resulted in a major decrease in rUro potency against all Kv channels tested, without perturbing the toxin's structure. Reciprocal mutations in the pore of Uro-sensitive Kv1.2 and Uro-resistant Kv1.5 channels revealed a direct interaction between Urotoxin and the Kv channel pore. Our experimental work supports postulating a mechanism of action in which occlusion of the permeation pathway by the K25 residue in Urotoxin is the basis of its Kv1 inhibitory activity. Docking analysis was consistent with occlusion of the pore by K25 and the requirement of a small, non-charged amino acid in the Kv1 channel vestibule to facilitate toxin-channel interactions. Finally, computational studies revealed key interactions between the amidated C-terminus of Urotoxin and a conserved Asp residue in the turret of Kv1 channels, offering a potential rationale for potency differences between native and recombinant Urotoxin.
Tárgyszavak:	Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk
Megjelenés:	Biochemical Pharmacology. - 174 (2020), p. 1-15. -
További szerzők:	Csóti Ágota (1989-) (biológus) McArthur, Jeffrey R. Chin, Yanni K. Y. Anangi, Raveendra Najera, Rosby del Carmen Possani, Lourival Domingos King, Glenn F. Panyi György (1966-) (biofizikus) Yu, Haibo Adams, David J. Finol-Urdaneta, Rocio K.
Pályázati támogatás:	GINOP-2.3.2-15-2016-00044 GINOP NKFIH K119417 Egyéb
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001-es BibID:	BIBFORM076188
035-os BibID:	(WoS)000442351000026 (Scopus)85051815682
Első szerző:	Richards, Kay L.
Cím:	Selective NaV 1.1 activation rescues Dravet syndrome mice from seizures and premature death / Richards Kay L., Milligan Carol J., Richardson Robert J., Jancovski Nikola, Grunnet Morten, Jacobson Laura H., Undheim Eivind A. B., Mobli Mehdi, Chow Chun Yuen, Herzig Volker, Csoti Agota, Panyi Gyorgy, Reid Christopher A., King Glenn F., Petrou Steven
Dátum:	2018
ISSN:	0027-8424 1091-6490
Megjegyzések:	Dravet syndrome is a catastrophic, pharmacoresistant epileptic encephalopathy. Disease onset occurs in the first year of life, followed by developmental delay with cognitive and behavioral dysfunction and substantially elevated risk of premature death. The majority of affected individuals harbor a loss-of-function mutation in one allele of SCN1A, which encodes the voltage-gated sodium channel Na V 1.1. Brain Na 1.1 is primarily localized to fast-spiking inhibitory interneurons; thus the mechanism of epileptogenesis in Dravet syndrome is hypothesized to be reduced inhibitory neurotransmission leading to brain hyperexcitability. We show that selective activation of Na V V 1.1 by venom peptide Hm1a restores the function of inhibitory interneurons from Dravet syndrome mice without affecting the firing of excitatory neurons. Intracerebroventricular infusion of Hm1a rescues Dravet syndrome mice fromseizures and premature death. This precision medicine approach, which specifically targets the molecular deficit in Dravet syndrome, presents an opportunity for treatment of this intractable epilepsy.
Tárgyszavak:	Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk genetic epilepsy spider venom targeted drug therapy seizures Dravet syndrome
Megjelenés:	Proceedings Of The National Academy Of Sciences Of The United States Of America. - 115 : 34 (2018), p. E8077-E8085. -
További szerzők:	Milligan, Carol J. Richardson, Robert J. Jancovski, Nikola Grunnet, Morten Jacobson, Laura H. Undheim, Eivind A. B. Mobli, Mehdi Chow, Chun Yuen Herzig, Volker Csóti Ágota (1989-) (biológus) Panyi György (1966-) (biofizikus) Reid, Christopher A. King, Glenn F. Petrou, Steven
Pályázati támogatás:	GINOP-2.3.2-15-2016-00044 GINOP Australian National Health and Medical Research Council Program Grant 10915693 Egyéb by Citizen's United for Research in Epilepsy Pediatrics Award 353711 Egyéb Principal Research Fellowships Egyéb
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