Biochem/physiol Actions

ML349 is a substrate-competitive, reversible and APT2-selective acyl-protein thioesterase (APT) inhibitor (IC₅₀/K_i = 510 nM/230 nM against APT2; IC₅₀ & K_i >10 µM against APT1). ML349 effectively inhibits cellular APT2 activity in cultures (by >95% in HEK293T & mouse T cells; 5 µM for 4 h) and in mice in vivo (by >90% in lung/heart/kidney and by ~50% in brain tissue 4 h post 50 mg/kg i.p. dosing) without affecting more than 15 cellular serine hydrolases and APT1. ML349 treatment (5 µM) is shown to restore palmitoylation and membrane localization of the multidomain scaffolding protein Scribble (Scrib) in MDCK cells overexpressing the epithelial-to-mesenchymal transcription factor (EMT-TF) Snail.