New Insights into the Type II Toxins from the Sea Anemone Heteractis crispa.

ABSTRACT: Toxins modulating Na_V channels are the most abundant and studied peptide components of sea anemone venom. Three type-II toxins, δ-SHTX-Hcr1f (= RpII), RTX-III, and RTX-VI, were isolated from the sea anemone Heteractis crispa. RTX-VI has been found to be an unusual analog of RTX-III. The electrophysiological effects of Heteractis toxins on nine Na_V subtypes were investigated for the first time. Heteractis toxins mainly affect the inactivation of the mammalian Na_V channels expressed in the central nervous system (Na_V1.1-Na_V1.3, Na_V1.6) as well as insect and arachnid channels (BgNa_V1, VdNa_V1). The absence of Arg13 in the RTX-VI structure does not prevent toxin binding with the channel

SUBMITTER: Kalina RS 

PROVIDER: S-EPMC7020476 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature