Figure 5. The RSK inhibitor BI-D1870 does not function through inhibition of ZIP kinase.

The elution of full length GFP-ZIPK off of γ phosphate linked ATP resin in the presence of 100 mM ATP, 50µM BI-D1870 or blank buffer (2% DMSO) is shown. We used 100 mM ATP because of the dense resin concentration (10 mM). 100 mM ATP gives a maximal signal. The small signal given by BI-D1870 above background (2% DMSO) is not considered relevant.