A. Reciprocal Co-IP of USP44 and USP7. HEK293T cells were transfected with constructs encoding MYC-USP44 and FLAG-USP7. These cells were lysed and pertinent factors were immunoprecipitated using either anti-FLAG or anti-MYC. Pulled-down proteins were observed by immunoblot analysis using either anti-MYC or anti-FLAG antibodies. 