A yeast chemical genetics approach identifies the compound 3,4,5‐trimethoxybenzyl isothiocyanate as a calcineurin inhibitor.

The phosphatase enzyme calcineurin controls gene expression in a variety of biological contexts however few potent inhibitors are currently available. A screen of 360 plant extracts for inhibition of calcineurin‐dependent gene expression in the model organism identified the compound 3,4,5‐trimethoxybenzyl isothiocyanate as an inhibitor. The compound was subsequently shown to inhibit human calcineurin via a mixed inhibition mechanism. To gain further mechanistic insight a yeast haploinsufficiency screen of 1152 deletion strains was carried out using a novel liquid medium screening method. The resulting haploinsufficiency profile is similar to that reported for the known calcineurin inhibitor FK506.