Fig. 3
Expression of Mdm2 is initially decreased and later increased in response to a high dose of UV irradiation
(A) Northern analysis. Primary MEF were treated with a UV dose of 20 J/M2, and then harvested at each indicated time following treatment. Total cellular RNA was isolated and 20 µg of each was used in Northern analysis. The mRNA levels of mdm2, p21/WAF1 and GAPDH were examined with each cDNA probe as indicated. (B) Quantitation of the mRNA levels of mdm2 and p21/WAF1. The amount of 32P-labeled probe bound to the Northern blots was quantified on a Phospho-Imager. The relative mRNA level was calculated by dividing the amount of mRNA at each time following UV treatment by the original level with no treatment. The relative mRNA levels of mdm2 and p21/WAF1 at each time after UV were plotted as indicated. The GAPDH signal was used as a loading control.