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Cucurbitacins: elucidation of their interactions with the cytoskeleton.

ABSTRACT: Cucurbitacins, a class of toxic tetracyclic triterpenoids in Cucurbitaceae, modulate many molecular targets. Here we investigated the interactions of cucurbitacin B, E and I with cytoskeletal proteins such as microtubule and actin filaments. The effects of cucurbitacin B, E and I on microtubules and actin filaments were studied in living cells (Hela and U2OS) and in vitro using GFP markers, immunofluorescence staining and in vitro tubulin polymerization assay. Cucurbitacin B, E and I apparently affected microtubule structures in living cells and cucurbitacin E inhibited tubulin polymerization in vitro with IC50 value of 566.91 ± 113.5 µM. Cucurbitacin E did not affect the nucleation but inhibited the growth phase and steady state during microtubule assembly in vitro. In addition, cucurbitacin B, E and I all altered mitotic spindles and induced the cell cycle arrest at G2/M phase. Moreover, they all showed potent effects on actin cytoskeleton by affecting actin filaments through the depolymerization and aggregation. The interactions of cucubitacin B, E and I with microtubules and actin filaments present new insights into their modes of action.

SUBMITTER: Wang X

PROVIDER: S-EPMC5452965 | biostudies-other | 2017

REPOSITORIES: biostudies-other

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Cucurbitacins: elucidation of their interactions with the cytoskeleton.

Wang Xiaojuan X Tanaka Mine M Peixoto Herbenya Silva HS Wink Michael M

PeerJ 20170530

Cucurbitacins, a class of toxic tetracyclic triterpenoids in Cucurbitaceae, modulate many molecular targets. Here we investigated the interactions of cucurbitacin B, E and I with cytoskeletal proteins such as microtubule and actin filaments. The effects of cucurbitacin B, E and I on microtubules and actin filaments were studied in living cells (Hela and U2OS) and <i>in vitro</i> using GFP markers, immunofluorescence staining and <i>in vitro</i> tubulin polymerization assay. Cucurbitacin B, E and ...[more]

PMID: 28584704

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Dataset Information

Cucurbitacins: elucidation of their interactions with the cytoskeleton.

Publications

Cucurbitacins: elucidation of their interactions with the cytoskeleton.

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