Figure 1.

Autoradiograms demonstrating repair in each strand of the RPB2 gene in a strain containing a galactose-inducible RSP5 gene, GAL-RSP5. Exponentially growing cultures at 30°C were induced with galactose or were repressed with glucose for 18–22 h, were UV-irradiated and incubated in growth medium at 30°C for the times indicated. UV irradiations were with 60 J/m². DNA purified from the cells was digested with PvuI and PvuII restriction endonucleases. A portion (0.2 μg) of restricted DNA was digested with T4 endonuclease V or was mock-treated, then was electrophoresed through 0.5% alkaline agarose. DNA was transferred to Hybond N⁺ membrane and was hybridized with an RNA probe specific for the nontranscribed strand of the RPB2 gene, and an autoradiogram was generated. The probe was removed, and the immobilized DNA was then hybridized with an RNA probe specific for the transcribed strand. The autoradiograms show the 5.3-kb PvuI-PvuII restriction fragment.