FMK 9a

FMK 9a is an autophagin-1 inhibitor with IC50 values of 80 and 73 μM in FRET and LRA assay.

Signaling Pathways >> Autophagy >> Autophagy

Research Areas >> Cancer

IC50: 80 nM (autophagin-1, FRET assay); 73 nM (autophagin-1, LRA assay)[1]

ATG4B or autophagin-1 is a cysteine protease that cleaves ATG8 family proteins. ATG4B plays essential roles in the autophagosome formation and the autophagy pathway. FMK 9a shows strong inhibition of ATG4B, with IC50 values of 80 and 73 nM in the TR-FRET and cellular-based LRA assays, respectively. LC−MS/MS study indicates that FMK 9a forms an irreversible covalent bond with the more reactive thiol group of Cys74 located at the catalytic site of ATG4B and thus inactivates ATG4B proteolytic activity[1].

FMK 9a shows moderate solubility (LYSA: 41 μg/mL) and high human and mouse liver microsome clearances of 13.9 and 70 mL/kg per minute[1].

FMK 9a is dissolved in DMSO. 5 μL of serial-diluted FMK 9a (1% DMSO) in assay buffer is added into 5 μL of purified ATG4B (final 0.1 nM) in 384-well plate, and the solution is incubated at room temperature (rt) for 30 min. Then, 5 μL of His-GATE-16-GST (final 20 nM) is added into the wells, and the solution is incubated for another 30 min. 5 μL of detection solution (final 2 nM of Eu-anti-His and 20 nM of Ulight-anti-GST) is added, and the resulting mixture is incubated at rt for 40 min[1].

[1]. Qiu Z, et al. Discovery of Fluoromethylketone-Based Peptidomimetics as Covalent ATG4B (Autophagin-1) Inhibitors. ACS Med Chem Lett. 2016 Jun 25;7(8):802-6.

Rapamycin (Sirolimus) | MG-132 | Cycloheximide | 3-Methyladenine | LY294002 | TAK-242 | (+)-JQ1 | SB203580 | Pyrazolanthrone (SP600125) | U0126-EtOH | Actinomycin D | Chloroquine diphosphate | CHIR-99021 (CT99021) | MK-2206 2HCl | Dorsomorphin dihydrochloride