Nuclear protein extract and in vitro translation of Sox6.
Nuclear extracts were prepared from MEL cells (2 x 107) using a kit (Active Motif, Carlsbad, California, United States). The Sox6 in vitro translation expression vector, tagged with c-Myc and HA, was described before [15]. The translation was performed in a reticulocyte lysate based in vitro translational system (TNT(R) Quick Coupled Transcription/Translation Systems, Promega). A vector without the Sox6 coding sequence was also translated as a negative control. 
