ERα recruits the Rho-associated kinase, ROCK-2.

<p>Breast cancer cells were treated for 15 min with 10 nM E2 in the presence or absence of the ROCK-2 inhibitor, Y-27632 (Y; 10 µM), ICI 182,720 (ICI; 1 µM), or PTX (100 ng/ml). Wild-type moesin (moesin) or Thr⁵⁵⁸-phosphorylated (P-moesin) moesin were assayed in T47-D (A) or MCF-7 (B) cell extracts. C) T47-D cancer cell protein extracts were immunoprecipitated with an Ab. vs. ROCK-2 and the IPs were used to perform kinase assays using de-phosphorylated myelin basic protein (MBP) as a bait. The lower box shows phosphorylation of MBP, the upper boxes show the re-blot of the membranes for ROCK-2, ERα or ERβ. D and E) T47-D cell protein extracts were immunoprecipitated with an Ab. vs. ERα (D) or ROCK-2 (E) and co-immunoprecipitation of ROCK-2 or ERα was assayed with western analysis. The membranes were re-blotted for ERα or ROCK-2 to show equal input. F) Breast cancer cell protein extracts were immunoprecipitated with an Ab. vs. ERα and the IPs were used to perform kinase assays using de-phosphorylated myelin basic protein (MBP) as a bait. The lower box shows phosphorylation of MBP, the upper box shows the re-blot of the membrane for the immunoprecipitated protein.