TCDB is operated by the Saier Lab Bioinformatics Group

8.B.10 The Psalmotoxin-1 (PcTx1) Family

Psalmotoxin-1 is spider toxin that is selective and high affinity inhibitor of ASIC1a. PcTx1 inhibits ASIC1a homomers with an affinity of 0.7 nM without any effect on ASIC1a containing heteromers. It thus helped to characterize ASIC1a homomeric channels in peripheric and central neurons. PcTx1 acts as a gating modifier since it shifts the channel from the resting to an inactivated state by increasing its affinity for H(+) (Diochot et al., 2007). PcTx1 homologous to cystine knot toxin of Chilobrachys jingzhao (38% identity). The 3-d structure of PcTx1 has been solved by NMR (1LMM_A; Escoubas et al. 2003). The binding of PcTx1 to ASIC1a channels (1.A.6) depends on the β-sheet and β-turn linking and residues known to be implicated in channel recognition of other inhibitory cystine knot (ICK) toxins.

This family belongs to the: Conotoxin Superfamily.

References associated with 8.B.10 family:

A, J.Y., G.J. Wang, J.G. Sun, Y.C. Gu, M.S. Wu, and J.H. Liu. (2006). Identification of phase I and phase II metabolites of Guanfu base A hydrochloride in human urine. Eur J Drug Metab Pharmacokinet 28: 265-272. 14743967
Adão, R., R. Seixas, P. Gomes, J.C. Pessoa, and M. Bastos. (2008). Membrane structure and interactions of a short Lycotoxin I analogue. J Pept Sci 14: 528-534. 18098329
Chagot, B., P. Escoubas, E. Villegas, C. Bernard, G. Ferrat, G. Corzo, M. Lazdunski, and H. Darbon. (2004). Solution structure of Phrixotoxin 1, a specific peptide inhibitor of Kv4 potassium channels from the venom of the theraphosid spider Phrixotrichus auratus. Protein. Sci. 13: 1197-1208. 15096626
Chagot, B., P. Escoubas, S. Diochot, C. Bernard, M. Lazdunski, and H. Darbon. (2005). Solution structure of APETx2, a specific peptide inhibitor of ASIC3 proton-gated channels. Protein. Sci. 14: 2003-2010. 15987885
Diochot, S., M. Salinas, A. Baron, P. Escoubas, and M. Lazdunski. (2007). Peptides inhibitors of acid-sensing ion channels. Toxicon 49: 271-284. 17113616
Escoubas, P., C. Bernard, G. Lambeau, M. Lazdunski, and H. Darbon. (2003). Recombinant production and solution structure of PcTx1, the specific peptide inhibitor of ASIC1a proton-gated cation channels. Protein. Sci. 12: 1332-1343. 12824480
Hughes, S.R., P.F. Dowd, R.E. Hector, T. Panavas, D.E. Sterner, N. Qureshi, K.M. Bischoff, S.S. Bang, J.A. Mertens, E.T. Johnson, X.L. Li, J.S. Jackson, R.J. Caughey, S.B. Riedmuller, S. Bartolett, S. Liu, J.O. Rich, P.J. Farrelly, T.R. Butt, J. Labaer, and M.A. Cotta. (2008). Lycotoxin-1 insecticidal peptide optimized by amino acid scanning mutagenesis and expressed as a coproduct in an ethanologenic Saccharomyces cerevisiae strain. J Pept Sci 14: 1039-1050. 18465835
Santos, D.M., R.M. Verly, D. Piló-Veloso, M. de Maria, M.A. de Carvalho, P.S. Cisalpino, B.M. Soares, C.G. Diniz, L.M. Farias, D.F. Moreira, F. Frézard, M.P. Bemquerer, A.M. Pimenta, and M.E. de Lima. (2010). LyeTx I, a potent antimicrobial peptide from the venom of the spider Lycosa erythrognatha. Amino Acids 39: 135-144. 19946788
Yu, H., L. Yang, L. Liu, X. Zhao, and X. Huang. (2017). Molecular dynamics simulations investigate the Mechanism of Psalmotoxin 1 regulating gating process of an Acid-sensing ion channel 1a at pH 5.5. J Biomol Struct Dyn 1-21. [Epub: Ahead of Print] 28768463