FIG. 5.

Stability of HSP70 mRNA in BDV-infected glial cells. C6 cells were exposed to heat stress at 44°C for 1 h and allowed to recover at 37°C for the times indicated. (A) Total RNA was extracted, and semiquantitative RT-PCR for HSP70 mRNA was performed as described in Materials and Methods. As a control for the input RNA, the GAPDH transcript in the cells was also amplified. The amplification products were analyzed by 1.5% agarose gel electrophoresis. Gels were stained with ethidium bromide. The images of agarose gels were captured electronically, and the pixels were inverted. Data from one experiment representative of three independent tests are shown. (B) For quantitative analysis, band intensities were determined with NIH Image software. Values were normalized to GAPDH levels. The data are expressed as the mean plus the standard error. (C) C6 cells were exposed to heat stress at 44°C for 1 h and then allowed to recover at 37°C for various times in the presence of actinomycin D. Total RNA was extracted, and levels of HSP70 mRNA in the extract were analyzed by Northern blotting as described in Materials and Methods. The levels of 28S and 18S rRNAs are also shown. NT, nontreated control cells.