title: Isolation of a Nav channel blocking polypeptide from Cyanea capillata medusae - a neurotoxin contained in fishing tentacle isorhizas.
abstract: Jellyfish are efficient predators which prey on crabs, fish larvae, and small fish. Their venoms consist of various toxins including neurotoxins that paralyse prey organisms immediately. One possible mode of action of neurotoxins is the blockage of voltage-gated sodium (Na(v)) channels. A novel polypeptide with Na(v) channel blocking activity was isolated from the northern Scyphozoa Cyanea capillata (L., 1758). For that purpose, a bioactivity-guided multidimensional liquid chromatographic purification method has been developed. A neurotoxic activity of resulting chromatographic fractions was demonstrated by a bioassay, which based on the mouse neuroblastoma cell line Neuro2A. The purification process yielded one fraction containing a single polypeptide with proven activity. The molecular weight of 8.22 kDa was determined by matrix-assisted laser desorption time-of-flight mass spectrometry (MALDI-ToF MS). Utilising Laser Microdissection and Pressure Catapulting (LMPC) for the separation of different nematocyst types in combination with direct MALDI-ToF MS analysis of the intact capsules, the neurotoxin was found to be present in all types of fishing tentacle isorhizas (A-isorhizas, a-isorhizas, O-isorhizas) of C. capillata medusae.
authors.affiliation: Helmholtz-Zentrum Geesthacht, Centre for Materials and Coastal Research, Institute of Coastal Research, Department for Marine Bioanalytical Chemistry, Max-Planck-St. 1, 21502 Geesthacht, Germany. stephan.lassen@hzg.de
authors.forename: Stephan
authors.initials: S
authors.lastname: Lassen
authors.forename: Annika
authors.initials: A
authors.lastname: Wiebring
authors.forename: Heike
authors.initials: H
authors.lastname: Helmholz
authors.forename: Christiane
authors.initials: C
authors.lastname: Ruhnau
authors.forename: Andreas
authors.initials: A
authors.lastname: Prange
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D051379:Mice; D008970:Molecular Weight; D009498:Neurotoxins / Q000302:isolation & purification* / Q000633:toxicity; D037401:Scyphozoa / Q000472:pathogenicity*; D026941:Sodium Channel Blockers / Q000302:isolation & purification* / Q000633:toxicity; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D009498:Neurotoxins; D026941:Sodium Channel Blockers