Immunoblot for XBP1 splicing and DD fusion levels after UPR induction with tunicamycin.

cDD and eDD cells were cultured with Shield-1 for 96 hours prior to Shield-1 removal. Shield-1 washout with recombinant FBKP (5 µM) media occurred at various times in the presence or absence of tunicamycin (5 µM). (A) Blotting for XBP1 shows the spliced variant XBP(S) occurring at 4 and 8 hours when treated with tunicamycin. The blot was re-probed for XFP to assess the Shield-1 dependence of cDD and eDD. (*) A non-specific band in XBP1 staining is present in all lanes, including untransduced HEK293 cells (293). (B) Densitometry of DD fusion levels in the cytoplasm and ER after Shield-1 washout.