Fig. 4.

Inhibitors of MRCK described in the literature. The natural compounds a chelerythrine, b cycloartane-3,24,25-triol and c staurosporine have all been described as MRCK inhibitors. However, the lack of selectivity for chelerythine and staurosporine limit their value as chemical biology tools. The potency of cycloartane-3,24,25-triol in vitro and in vivo remains to be determined. d ROCK inhibitor Y-27632 has some effect on MRCK activity in vitro and in vivo at low micromolar concentrations, which suggests that some studies using it at concentrations in excess of 10 μM may be affecting both ROCK and MRCK function