Tags

Type your tag names separated by a space and hit enter

Isolation, synthesis and characterization of ω-TRTX-Cc1a, a novel tarantula venom peptide that selectively targets L-type Cav channels.
Biochem Pharmacol. 2014 May 15; 89(2):276-86.BP

Abstract

Spider venoms are replete with peptidic ion channel modulators, often with novel subtype selectivity, making them a rich source of pharmacological tools and drug leads. In a search for subtype-selective blockers of voltage-gated calcium (CaV) channels, we isolated and characterized a novel 39-residue peptide, ω-TRTX-Cc1a (Cc1a), from the venom of the tarantula Citharischius crawshayi (now Pelinobius muticus). Cc1a is 67% identical to the spider toxin ω-TRTX-Hg1a, an inhibitor of CaV2.3 channels. We assembled Cc1a using a combination of Boc solid-phase peptide synthesis and native chemical ligation. Oxidative folding yielded two stable, slowly interconverting isomers. Cc1a preferentially inhibited Ba(2+) currents (IBa) mediated by L-type (CaV1.2 and CaV1.3) CaV channels heterologously expressed in Xenopus oocytes, with half-maximal inhibitory concentration (IC50) values of 825nM and 2.24μM, respectively. In rat dorsal root ganglion neurons, Cc1a inhibited IBa mediated by high voltage-activated CaV channels but did not affect low voltage-activated T-type CaV channels. Cc1a exhibited weak activity at NaV1.5 and NaV1.7 voltage-gated sodium (NaV) channels stably expressed in mammalian HEK or CHO cells, respectively. Experiments with modified Cc1a peptides, truncated at the N-terminus (ΔG1-E5) or C-terminus (ΔW35-V39), demonstrated that the N- and C-termini are important for voltage-gated ion channel modulation. We conclude that Cc1a represents a novel pharmacological tool for probing the structure and function of L-type CaV channels.

Authors+Show Affiliations

Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD 4072, Australia. Electronic address: j.klint@imb.uq.edu.au.Health Innovations Research Institute, RMIT University, Bundoora, VIC 3083, Australia. Electronic address: geza.berecki@rmit.edu.au.Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD 4072, Australia. Electronic address: t.durek@imb.uq.edu.au.Centre for Advanced Imaging, The University of Queensland, St Lucia, QLD 4072, Australia. Electronic address: m.mobli@uq.edu.au.Health Innovations Research Institute, RMIT University, Bundoora, VIC 3083, Australia. Electronic address: knapplowitsch@yahoo.de.Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD 4072, Australia. Electronic address: g.king2@uq.edu.au.Health Innovations Research Institute, RMIT University, Bundoora, VIC 3083, Australia. Electronic address: david.adams@rmit.edu.au.Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD 4072, Australia. Electronic address: P.Alewood@imb.uq.edu.au.Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD 4072, Australia. Electronic address: l.rash@uq.edu.au.

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

24561180

Citation

Klint, Julie K., et al. "Isolation, Synthesis and Characterization of ω-TRTX-Cc1a, a Novel Tarantula Venom Peptide That Selectively Targets L-type Cav Channels." Biochemical Pharmacology, vol. 89, no. 2, 2014, pp. 276-86.
Klint JK, Berecki G, Durek T, et al. Isolation, synthesis and characterization of ω-TRTX-Cc1a, a novel tarantula venom peptide that selectively targets L-type Cav channels. Biochem Pharmacol. 2014;89(2):276-86.
Klint, J. K., Berecki, G., Durek, T., Mobli, M., Knapp, O., King, G. F., Adams, D. J., Alewood, P. F., & Rash, L. D. (2014). Isolation, synthesis and characterization of ω-TRTX-Cc1a, a novel tarantula venom peptide that selectively targets L-type Cav channels. Biochemical Pharmacology, 89(2), 276-86. https://doi.org/10.1016/j.bcp.2014.02.008
Klint JK, et al. Isolation, Synthesis and Characterization of ω-TRTX-Cc1a, a Novel Tarantula Venom Peptide That Selectively Targets L-type Cav Channels. Biochem Pharmacol. 2014 May 15;89(2):276-86. PubMed PMID: 24561180.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Isolation, synthesis and characterization of ω-TRTX-Cc1a, a novel tarantula venom peptide that selectively targets L-type Cav channels. AU - Klint,Julie K, AU - Berecki,Géza, AU - Durek,Thomas, AU - Mobli,Mehdi, AU - Knapp,Oliver, AU - King,Glenn F, AU - Adams,David J, AU - Alewood,Paul F, AU - Rash,Lachlan D, Y1 - 2014/02/19/ PY - 2013/12/17/received PY - 2014/02/10/revised PY - 2014/02/10/accepted PY - 2014/2/25/entrez PY - 2014/2/25/pubmed PY - 2014/6/4/medline KW - Citharischius crawshayi KW - Peptide isomer KW - Tarantula KW - Venom-peptide KW - Voltage-gated calcium channel KW - Voltage-gated sodium channel SP - 276 EP - 86 JF - Biochemical pharmacology JO - Biochem. Pharmacol. VL - 89 IS - 2 N2 - Spider venoms are replete with peptidic ion channel modulators, often with novel subtype selectivity, making them a rich source of pharmacological tools and drug leads. In a search for subtype-selective blockers of voltage-gated calcium (CaV) channels, we isolated and characterized a novel 39-residue peptide, ω-TRTX-Cc1a (Cc1a), from the venom of the tarantula Citharischius crawshayi (now Pelinobius muticus). Cc1a is 67% identical to the spider toxin ω-TRTX-Hg1a, an inhibitor of CaV2.3 channels. We assembled Cc1a using a combination of Boc solid-phase peptide synthesis and native chemical ligation. Oxidative folding yielded two stable, slowly interconverting isomers. Cc1a preferentially inhibited Ba(2+) currents (IBa) mediated by L-type (CaV1.2 and CaV1.3) CaV channels heterologously expressed in Xenopus oocytes, with half-maximal inhibitory concentration (IC50) values of 825nM and 2.24μM, respectively. In rat dorsal root ganglion neurons, Cc1a inhibited IBa mediated by high voltage-activated CaV channels but did not affect low voltage-activated T-type CaV channels. Cc1a exhibited weak activity at NaV1.5 and NaV1.7 voltage-gated sodium (NaV) channels stably expressed in mammalian HEK or CHO cells, respectively. Experiments with modified Cc1a peptides, truncated at the N-terminus (ΔG1-E5) or C-terminus (ΔW35-V39), demonstrated that the N- and C-termini are important for voltage-gated ion channel modulation. We conclude that Cc1a represents a novel pharmacological tool for probing the structure and function of L-type CaV channels. SN - 1873-2968 UR - https://www.unboundmedicine.com/medline/citation/24561180/Isolation_synthesis_and_characterization_of_ω_TRTX_Cc1a_a_novel_tarantula_venom_peptide_that_selectively_targets_L_type_Cav_channels_ L2 - https://linkinghub.elsevier.com/retrieve/pii/S0006-2952(14)00102-6 DB - PRIME DP - Unbound Medicine ER -