Triple SILAC identified progesterone-independent and dependent PRA and PRB interacting partners in human breast cancer cells

Progesterone receptor (PR) isoforms, PRA and PRB, both progesterone-independent and dependent modulated the biology of breast cancer cells. The different phenotypes in breast cancer mediated by PRA and PRB could due to the differences of their structures, leading to the distinct protein interacting partners and downstream signaling events of each receptor. Here, we constructed Tet-inducible HA-tagged PRA or HA-tagged PRB in T47DC42 breast cancer cells. We performed affinity purification coupled with SILAC mass spectrometry technique to comprehensively study PRA and PRB interacting partners in both liganded and unliganded conditions. To validate our findings, we applied both forward and reverse SILAC to effectively minimize experimental errors. These datasets will be useful in investigating PRA- and PRB-specific molecular mechanisms and can potentially be used as a database for subsequent experiments to identify novel PRA and PRB interacting proteins that differentially mediated different biological functions in breast cancer cells.