%0 Journal Article
%T The ubiquitin-proteasome pathway inhibitor TAK-243 has major effects on calcium handling in mammalian cells.
%A Gao X
%A Keller KR
%A Bonzerato CG
%A Li P
%A Laemmerhofer M
%A Wojcikiewicz RJH
%J Biochim Biophys Acta Mol Cell Res
%V 1871
%N 1
%D 2024 01 29
%M 37907195
%F 5.011
%R 10.1016/j.bbamcr.2023.119618
%X The ubiquitin-proteasome pathway (UPP) is a major route for protein degradation and a key regulatory mechanism in mammalian cells. UPP inhibitors, including TAK-243, a first-in-class inhibitor of the E1 ubiquitin-activating enzyme, are currently being used and tested for treatment of a range of diseases, particularly cancer. Here, we reveal that TAK-243 has major effects on Ca2+ handling in a range of cultured mammalian cells (αT3, HeLa and SH-SY5Y). Effects were seen on agonist-induced Ca2+ mobilization, basal cytosolic Ca2+ levels, Ca2+ leak from the endoplasmic reticulum (ER), store-operated Ca2+ entry and mitochondrial Ca2+ uptake. These effects correlated with induction of ER stress, as measured by PERK activation / eIF2α phosphorylation, and most seemed to be underpinned by enhanced Ca2+ leak from the ER. Overall, these data indicate that TAK-243 reprograms the Ca2+-handling properties of mammalian cells and that these effects should be considered when UPP inhibitors are employed as therapeutic agents.