FIG. 5.

Reduced expression of radiation-responsive genes in fibroblasts derived from Sod2 (MnSOD) knockout mice. Expression of p21, Myc, 14-3-3 zeta, cyclin A, cyclin B1, and GADD153 as well as two control genes (α-catenin and GAPDH) was measured by RT-PCR 24 h following 5-Gy irradiation in fibroblasts from wild-type (+/+), homozygous (−/−), and heterozygous (+/−) Sod2 knockout mice. PCR primers were synthesized according to sequence data from GenBank. Expression levels were measured using densitometry and normalized to +/+ cells (right panel; the data represent the mean ± 1 standard deviation of three densitometric analyses of the single set of PCR analyses which are shown).