Figure 9.

Phosphorylation of the myosin regulatory light chain in the isolated stress fiber. Fractionated stress fibers were preincubated with 0 (lane 2), 100 (lane 3), or 5000 nM (lane 4) KT5926 for 30 min on ice and then incubated with Mg-[γ-³²P]ATP. Purified chicken gizzard heavy meromyosin (HMM) mixed with BSA was used as a molecular marker (lane 1). Phosphorylation of the myosin regulatory light chain is inhibited by KT5926 in a concentration-dependent manner. HC, HMM heavy chain; RLC, myosin regulatory light chain; ELC, myosin essential light chain.