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PubMed · 8902620

Novel actin depolymerizing macrolide aplyronine A.

S Saito·S Watabe·H Ozaki·H Kigoshi·K Yamada·N Fusetani·H Karaki
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Abstract

Aplyronine A is a macrolide isolated from Aplysia kurodai. By monitoring fluorescent intensity of pyrenyl-actin, it was found that aplyronine A inhibited both the velocity and the degree of actin polymerization. Aplyronine A also quickly depolymerized F-actin. The kinetics of depolymerization suggest that aplyronine A severs F-actin. The relationship between the concentration of total actin and F-actin at different concentrations of aplyronine A suggests that aplyronine A forms a 1:1 complex with G-actin. From these results, it is concluded that aplyronine A inhibits actin polymerization and depolymerizes F-actin by nibbling. Comparison of the chemical structure of aplyronine A and another actin-depolymerizing macrolide, mycalolide B, suggests that the side-chain but not the macrolide ring of aplyronine A may account for its actin binding and severing activity.

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ActinsAnimalsAplysiaEnzyme InhibitorsKineticsLactonesMacrolidesMarine ToxinsMuscle, SkeletalMyosinsOxazolesPhalloidineRabbitsSerineTropomyosinJournal ArticleResearch Support, Non-U.S. Gov't

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S Saito, S Watabe, H Ozaki, H Kigoshi, K Yamada, N Fusetani, H Karaki. 1996. Novel actin depolymerizing macrolide aplyronine A.. https://doi.org/10.1093/oxfordjournals.jbchem.a021449

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