FIG 6.

G444C mutation inhibits cleavage of BLOC1S1 by IRE1 in vivo. (A) SYBR green qPCR quantification of relative expression of total BLOC1S1 and qTag (exogenous BLOC1S1) mRNA in myeloma cell lines transduced with the indicated virus and treated with 2 mM DTT for 4 h. Measurements were normalized to GAPDH and are shown relative to untreated control cells. The data show means ± SEM from five independent experiments. *, P < 0.05; **, P < 0.01; ***, P < 0.001; unpaired t test. (B) Representative agarose gel electrophoresis of RT-PCR products surrounding the XBP1 splice site from the samples used in panel A.