Skepinone-L
Probe criteria
| Inhibitor/agonist potency: goal is < 100 nM (IC50, Kd>/sub>) | Surpasses criterion: MAPK14: IC50 = 5 nM (ELISA, cell free); KD = 1.5 nM (DiscoverX) |
| Selectivity within target family: > 30-fold | Surpasses criterion: >1000-fold selective (KinomeScan DiscoverX) |
| Selectivity outside target family | Closest off-targets in the PDSP scan are HTR2B (Ki = 172.4 nM) and TMEM97 (Ki = 3358.03 nM). |
| On target cell activity for cell-based targets: goal is < 1 µM IC50/EC50 | Surpasses criterion:NanaoBRET:MAPK14 IC50 = 13.6 nM; MAPK11 IC50 = 40.2 nM (full-length protein in HEK cells); Western: inhibition of HSP27 (Ser82) phosphorylation IC50 ≈ 25 nM |
| On target cell activity for secreted targets: appropriate alternative such as mouse model or other mechanistic biological assay, e.g., explant culture | Inhibition of TNFα release in WB: IC50 = 22-50 nM; Inhibition of Gal/LPS-induced TNF-α release in mice, 77% dosed at 3mg/kg p.o. |
| Control compound (100 times less potent than the probe) | Surpasses criterion: FM-743: IC50 (MAPK14/MAPK11) = 11.3/ 16.2 µM (NanoBRET) |