Supplementary Figure 1: PTAR1 specifically binds FBXL2 and RabGGTB.
From: GGTase3 is a newly identified geranylgeranyltransferase targeting a ubiquitin ligase
(a) IMR90 diploid fibroblasts and HEK293T cells were transfected with the indicated siRNA oligos. Seventy-two hours after siRNA transfection, cells were harvested for immunoblotting as indicated. NS: non-silencing. (b) HEK-293T cells were co-transfecetd with FLAG-tagged PTAR1 and either GFP-tagged FBXL15, GFP-tagged H-Ras, or GFP-tagged FBXL2. Twenty-four hours post-transfection, cells were harvested for immunoprecipitations and immunoblotting as indicated. (c) HEK-293T cells were transfected with the indicated siRNA oligos for 72 hours before cells were harvested for immunoblotting as indicated. NS: non-silencing, s.e.: short exposure, l.e: long exposure. (d,e) HEK-293T cells were transfected with FLAG-tagged PTAR1 and the indicated GFP-tagged substrates of FTase or GGTases. Twenty-four hours post-transfection, cells were harvested for immunoprecipitations and immunoblotting as indicated. The asterisks indicate bands visualized only after long exposures. s.e.: short exposure, l.e: long exposure. (f) HEK-293T cells were transfected with the indicated siRNA oligos for 48 hours followed by transfection with indicated cDNAs. Sixteen hours after transfection of the cDNAs, cells were lysed, and immunoprecipitations were performed with an anti-GFP antibody followed by immunoblotting as indicated. WCE: Whole cell extract. All experiments were repeated at least three times.
