Description

• A cell-permeable quinone epoxide antibiotic that acts as a reversible, substrate competitive, and selective inhibitor of Bruton’s tyrosine kinase catalytic activity (BTK; IC 50 = 10μM and 3μM for the basal and activation levels)
• Shown to bind to the BTK pleckstrin homology domain (BTK-PH) and block the interaction between the BTK-PH and PKC (IC 50 = ∽ 100μM in human mast cell lysates), thus affecting the catalytic activity of BTK, but not of PKC
• Selectively inhibits the autophosphorylating activity of PKC βI (IC 50 = ∽ 8μM) and not of PKC βII
• Reported to effectively inhibit the production of TNF-α (IC 50 = ∽ 3μM), and activation of JNK1 (IC 50 = ∽ 10μM) in FcεRI-stimulated mast cells
• Also inhibits the DNA synthesis in activated spleen cells (IC 50 = ∽ 1.5μM)
• Does not significantly affect the activities of Lyn, Syk, PKA, CK-1, ERK1, ERK2, and p38 kinases.