%0 Journal Article
%T Characterization of the RAS/RAF/ERK Signal Cascade as a Novel Regulating Factor in Alpha-Amanitin-Induced Cytotoxicity in Huh-7 Cells.
%A Kim D
%A Lee MS
%A Sung E
%A Lee S
%A Lee HS
%J Int J Mol Sci
%V 23
%N 20
%D Oct 2022 14
%M 36293151
%F 6.208
%R 10.3390/ijms232012294
%X The well-known hepatotoxicity mechanism resulting from alpha-amanitin (α-AMA) exposure arises from RNA polymerase II (RNAP II) inhibition. RNAP Ⅱ inhibition occurs through the dysregulation of mRNA synthesis. However, the signaling pathways in hepatocytes that arise from α-AMA have not yet been fully elucidated. Here, we identified that the RAS/RAF/ERK signaling pathway was activated through quantitative phosphoproteomic and molecular biological analyses in Huh-7 cells. Bioinformatics analysis showed that α-AMA exposure increased protein phosphorylation in a time-dependent α-AMA exposure. In addition, phosphorylation increased not only the components of the ERK signaling pathway but also U2AF65 and SPF45, known splicing factors. Therefore, we propose a novel mechanism of α-AMA as follows. The RAS/RAF/ERK signaling pathway involved in aberrant splicing events is activated by α-AMA exposure followed by aberrant splicing events leading to cell death in Huh-7 cells.