Rational design of Rho GTPase-targeting inhibitors.

Rho GTPases have been implicated in diverse cellular functions and are potential therapeutic targets in inflammation, cancer, and neurologic diseases. Virtual screening of compounds that fit into surface grooves of RhoA known to be critical for guanine nucleotide exchange factor (GEF) interaction produced chemical candidates with minimized docking energy. Subsequent screening for inhibitory activity of RhoA binding to the Rho-GEF, LARG, identified a Rho-specific inhibitor as a lead compound capable of blocking RhoA-LARG interaction and RhoA activation by LARG specifically and dose dependently. A microscale thermophoresis analysis was applied to directly quantify the binding interaction of the lead inhibitor with RhoA target. The lead inhibitor highlights the principle that rational targeting of subfamily members of Rho GTPases is feasible and potentially useful in future drug design effort.