BRCA1 binds NF2 through FERM and BRCT domains. (A) HEK293T cells expressing HA-tag Hippo proteins and GST or GST-BRCA1 fusion proteins were subjected to immunoprecipitation as described in Materials and Methods. (B) Endogenous NF2 was detected in anti-BRCA1 beads, but not control, immunoprecipitates. (C) HA-NF2 directly binds GST-BRCA1, as revealed by immunoprecipitation upon in vitro binding experiment, performed as described in Materials and Methods. (D) HEK293T cells expressing various mutants of BRCA1 and HA-NF2 were subjected to immunoprecipitation using HA-binding beads. The resulting eluent was used to measure HA-NF2–bound BRCA1 by immunoblotting with anti-BRCA1 antibody. (E) HEK293T cells expressing either full-length NF2, N-terminus fragment (1–332) or C-terminus fragment (308–590), and GST-BRCA1 were subjected to immunoprecipitation using GST-binding beads. The resulting eluent was used to measure GST-BRCA1–bound NF2 by immunoblotting with anti-NF2 antibody. (F) HEK293T cells expressing the indicated BRCA1 Myc-tag fragments (1–303, 303–772, 772–1314, and 1314–1863) were tested for interaction with HA-NF2.