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Quassinoid inhibition of AP-1 function does not correlate with cytotoxicity or protein synthesis inhibition.

ABSTRACT: Several quassinoids were identified in a high-throughput screening assay as inhibitors of the transcription factor AP-1. Further biological characterization revealed that while their effect was not specific to AP-1, protein synthesis inhibition and cell growth assays were inconsistent with a mechanism of simple protein synthesis inhibition. Numerous plant extracts from the plant family Simaroubaceae were also identified in the same screen; bioassay-guided fractionation of one extract (Ailanthus triphylla) yielded two known quassinoids, ailanthinone (3) and glaucarubinone (4), which were also identified in the pure compound screening procedure.

SUBMITTER: Beutler JA

PROVIDER: S-EPMC2837105 | biostudies-literature | 2009 Mar

REPOSITORIES: biostudies-literature

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Quassinoid inhibition of AP-1 function does not correlate with cytotoxicity or protein synthesis inhibition.

Beutler John A JA Kang Moon-Il MI Robert Francis F Clement Jason A JA Pelletier Jerry J Colburn Nancy H NH McKee Tawnya C TC Goncharova Ekaterina E McMahon James B JB Henrich Curtis J CJ

Journal of natural products 20090301 3

Several quassinoids were identified in a high-throughput screening assay as inhibitors of the transcription factor AP-1. Further biological characterization revealed that while their effect was not specific to AP-1, protein synthesis inhibition and cell growth assays were inconsistent with a mechanism of simple protein synthesis inhibition. Numerous plant extracts from the plant family Simaroubaceae were also identified in the same screen; bioassay-guided fractionation of one extract (Ailanthus ...[more]

PMID: 19199792

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