In this study, we used a combination of SILAC-MS proteomics and bioinformatic approaches to identify Checkpoint Kinase 1 (Chk1) as a possible POPX2 phosphatase interacting protein.  Subsequently, 46 proteins with Pkinase domain were identified from POPX2 SILAC-MS data. 
SILAC-MS
In this study, we used a combination of SILAC-MS proteomics and bioinformatic approaches to identify Checkpoint Kinase 1 (Chk1) as a possible POPX2 phosphatase interacting protein. 
bioinformatic approaches
From the Domain-Domain Interaction (DDI) database, we first determined that the PP2C phosphatase domain interacts with Pkinase domain. 
Domain-Domain Interaction (DDI) database