CHEMBL5734193

Enzyme Assay: Compounds were assessed in ALK1-6 enzymatic assays. Specifically, compounds were assayed using LANCE® Ultra ULight technology (Perkin Elmer) against human ALK1-6 enzymes (ALK1: Life Technologies, ALK2-6: Carna Biosciences). Briefly, ALK enzyme (10 nM) was prepared in kinase buffer (50 mM HEPES, pH 7.5, 10 mM MgCl2, 3 mM MgCl2, 0.005% Tween-20 and 2 mM DTT) and dispensed at 2.5 μL/well into a 1536 well, white, solid bottom, microtiter plate (Greiner, 789175-F). Negative controls for the assay were generated by adding one column containing kinase buffer only. Compounds in DMSO solution were transferred to the assay plates at 23 nL/well via a NX-TR pin tool workstation (WAKO, San Diego, Calif.) and incubated with enzyme for 10 minutes at ambient temperature. ULight Topo IIa Substrate (50 nM) was prepared in kinase buffer containing either 10 μM or 1000 μM ATP and dispensed at 2.5 μL/well into the assay plate. Following a 1 hour incubation at ambient temperature, Europium anti-phospho DNA Topoisomerase 2-alpha antibody (4 nM) was prepared in 1× LANCE detection buffer containing 12 mM EDTA and dispensed at 5 μL/well into the assay plate. Plates were measured using the EnVision plate reader (Perkin Elmer), with excitation 320 nm and emissions of 615 nm and 665 nm.