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PubMed · 10629885

[Actin depolymerizing action by marine toxin, pectenotoxin-2].

M Hori·Y Matsuura·R Yoshimoto·H Ozaki·T Yasumoto·H Karaki
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Abstract

Pectenotoxin-2 (PCTX-2), which is one of Diarrhetic Shellfish Poisoning (DSP), is a family of cyclic polyether macrolide toxin isolated from scallop Patinopecten yessoensis. Although PCTX-2 has a potent cytotoxic activities against several cancer cell lines, the biochemical activity of PCTX-2 has not been determined yet. To clarify the biochemical activity of PCTX-2 is the aime in this study. PCTX-2 inhibited the contractions elicited by 72.7 mM KCl or 1 microM phenyrephrine in a concentration dependent manner in the isolated rat aorta. In A10 cells, actin stressfiber in center but not in periphery of the cell was disrupted by PCTX-2 without any visible shape change. By monitoring fluorescent intensity of pyrenyl-actin, PCTX-2 was found to inhibit the velocity and the degree of actin polymerization in a concentration dependent manner. In addition, PCTX-2 decreased viscosity of F-actin measured with falling ball viscometry. Stoichiometric analysis indicated that PCTX-2 forms 1:4 complex with G-actin. These results suggest that PCTX-2 is a potent natural actin depolymerizing compound with unique mode of action.

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ActinsAnimalsAntineoplastic AgentsAortaFuransIn Vitro TechniquesMacrolidesMaleMarine ToxinsPolymersPyransRabbitsRatsRats, WistarVasoconstrictionPolyether ToxinsJournal Article

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BibTeXRIS

M Hori, Y Matsuura, R Yoshimoto, H Ozaki, T Yasumoto, H Karaki. 1999. [Actin depolymerizing action by marine toxin, pectenotoxin-2].. https://doi.org/10.1254/fpj.114.supplement_225

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