SJFδ

SJFδ is a p38δ PROTAC degrader with a DC₅₀ of 46.17 nM. SJFδ selectively induces ubiquitin-proteasome-dependent degradation of p38δ by forming a ternary complex with p38δ and the VHL E3 ligase, with no effect on other p38 isoforms or members of the MAPK family. SJFδ can be used for breast cancer research^[1][2][3][4]. In Vitro:PROTAC SJFδ forms a stable ternary complex with p38δ and VHL, with a ternary K_d of 436 nM and a dissociation half-life of 38 s, which is more stable than the ternary complex formed by the related PROTAC SJFα^[1].
PROTAC SJFδ does not induce substantial ubiquitination of p38α in transfected HeLa cells^[1].
SJFδ preferentially degrades p38δ kinase in cells with a DC₅₀ of 46 nM and a maximal degradation of 99%^[3].
SJFδ (0.025-2.5 μM) forms stable, dose-dependent ternary complexes with endogenous p38δ and VBC in MDA-MB-231 whole-cell lysate^[4].
SJFδ (up to 5 μM; 60 s injection, 300 s dissociation monitoring) forms a high-affinity p38δ:SJFδ:VHL ternary complex with a K_d of 436 nM, which has a longer half-life and stronger affinity than the p38δ:SJFα:VHL ternary complex^[4].
SJFδ (1 μM; 2 h) induces significant cellular ubiquitination of FLAG-p38δ in transfected HeLa cells^[4].
SJFδ (0.025-2.5 μM; 6 h-24 h) potently and selectively degrades p38δ with a DC₅₀ of 46.17 nM in MDA-MB-231 human breast cancer cells, via a rapid, sustained, proteasome-dependent mechanism, and also degrades mutant p38δ^K220E/T221E in HeLa cells^[4].