Fig. 3

Immunoblotting results. This procedure revealed a strong SOX17 protein band (green) in a HGSC cell line, OVSAHO (lane 1). The SOX17 band was also found in all of the examined OCCC cell lines (a) However, SOX17 band was notably smaller in OVTOKO OCCC cells (lane 3) compared to that of the OVISE (lane2) and RMG-V (lane 4) OCCC cells. The internal control, HDAC1, was stained red. SOX17 and HDAC1 bands were extracted as black and white bands (b and c, respectively). The polyubiquitinated SOX17 bands were found in OVTOKO cells (lane 3), but were present at diminished levels in the OVSAHO (lane 1), OVISE (lane 2), and RMG-V cells (lane 4) when they were treated with a proteasome inhibitor, MG132 (d). Input protein loads of cell lysates that were subjected to co-immunoprecipitation (IP) with anti-SOX17, followed by immunoblotting (WB) with anti-ubiquitin is shown as G3PDH bands (e). siRNA-mediated silencing of UCHL1 decreased the intensity of UCHL1 (f) and SOX17 (g) protein bands (lane 1, treated with control siRNA; lane 2, treated with Ambion siRNA ID: 105082) and moreover, increased polyubiquitinated SOX17 proteins (h). Equal input protein loads are shown as G3PDH bands. Similar results were also obtained using another siRNA ID: 105,646