PTENα physically interacts with moesin. (A) In vitro binding of PTENα and moesin. HEK293T cells were cotransfected with S-tag–PTENα and Flag-moesin, and cell lysates were pulled down with S-protein beads and subjected to immunoblot with FLAG or HA antibody. (B) In vitro binding of moesin and PTENα. HEK293T cells were cotransfected with Flag-moesin and GFP-PTENα, and cell lysates were pulled down with Flag beads and subjected to immunoblot with GFP or Flag antibody. (C) In vivo immunoprecipitation. Lysates of mouse thioglycollate-elicited peritoneal cells were immunoprecipitated with an anti-PTENα or anti-PTEN antibody and immunoblotted with an anti-moesin antibody. PTENα, but not PTEN, physically associates with moesin (lane 4 vs. lane 2). (D-E) PTENα binds to the moesin FERM region. (D) Sketch map of truncated moesin. (E) HEK293T cells were cotransfected with Flag-PTENα and the GFP-tagged FERM domain or the C-terminal ERM-association domain of moesin (C-ERMAD), and cell lysates were pulled down with anti-Flag antibody and subjected to immunoblot with GFP or Flag antibody. PTENα physically associates with FERM domain of moesin (lane 2 vs. lane 4). (F-G) The interaction between PTENα and the moesin-FERM domain depends on its sequence at the N terminus, which is not found in PTEN. (F) Diagram of multiple truncations or deletions of PTENα. (G) Different truncation or deletion vectors of PTENα and the GFP-tagged moesin-FERM domain were cotransfected into HEK293T cells, and cell lysates were pulled down with anti-Flag antibody and subjected to immunoblot with GFP or Flag antibody. The moesin FERM domain was not immunoprecipitated by PTENαΔ1-173 (lane 2) or PTENαΔ20-140 (lane 5). MBH, membrane binding helix; PHD, plekstrin homology domain.