Squarunkin A is a potent and selective UNC119-cargo interaction inhibitor, interrupting the UNC119A-myristoylated Src N-terminal peptide interaction (IC50=10 nM). Squarunkin A interferes with the activation of Src kinase in cells.IC50 & Target:IC50: 10 nM (UNC119A-myristoylated Src N-terminal peptide interaction)In Vitro:Squarunkin A (2.5 μM, 0.625 μM, 0.078 μM, and 0.01 μM) treatment leads to a concentration-dependent reduction of Src phosphorylation.
Squarunkin A does not target the lipoprotein-binding sites of other lipoprotein chaperones, such as PDE6d, AIPL1, and RhoGDI, which bind S-prenylated proteins. Squarunkin A binds to UNC119 in cell lysate and interferes with Src activation.