FIGURE 3:

PlexA remains ER- and polysome-associated during ER stress. (A) Shown are the FM values for the indicated mRNAs in the presence and absence of DTT (2 mM, 20 min), measured using detergent extraction (see Materials and Methods). Actin is shown as a cytosolic control, sparc and Hydr2 are RIDD targets, and the remaining mRNAs are protected from RIDD. (B–F) We either treated S2 cells with DTT (2 mM, 20 min, black bars) or left them untreated (gray bars), and then compared polysome association of the designated mRNAs using sucrose gradient fractionation. We collected RNA samples from the monosome peak (mono), the first four polysome peaks (low-density polysome, LP), and the denser polysome peaks (high-density polysome, HP), and analyzed mRNA content by qPCR. Shown is the average and SD of two to three independent experiments. Note the different scale for the y-axis for plexA. (G) FM values as in (A), but after longer DTT treatment.