Downregulation of COP9 signalosome subunits differentially affects the CSN complex and target protein stability-2

<p><b>Copyright information:</b></p><p>Taken from "Downregulation of COP9 signalosome subunits differentially affects the CSN complex and target protein stability"</p><p>http://www.biomedcentral.com/1471-2091/8/27</p><p>BMC Biochemistry 2007;8():27-27.</p><p>Published online 19 Dec 2007</p><p>PMCID:PMC2225408.</p><p></p>of cell lysates were analyzed by Western blotting using the anti-c-Jun antibody. The same samples were probed with the antibody against the 26S proteasome base subunit RPN2/S1 as a loading control. CSN5 knockdown cells were transfected with CSN5wt as in Fig. 1d or with CSN5D151N and 24 h after transfection CHX chase experiments were carried out as in (a). The middle panel shows Western blots with the anti-Flag antibody visualizing the expressed CSN5wt or CSN5D151N proteins CSN5wt was overexpressed in siCSN1 cells and after 24 h CHX experiments were performed as in (a). In all CHX experiments a band just above c-Jun appeared after 20 – 30 min, which cross-reacted with the anti-c-Jun antibody (in some blots it was cut off). This protein might be a modified c-Jun. The nature of this modification is currently unknown. Both the putative modified c-Jun as well as unmodified c-Jun disappeared during the experiment