Figure 6.
Strand-selective repair of CPDs in the MTIA gene. (A) Human primary fibroblasts were exposed to 10 J/m2 UV and were allowed to repair for the indicated times. EcoRI-digested genomic DNA was treated (+) or not (−) with T4 endonuclease V, electrophoresed, blotted, and hybridized with RNA probes that distinguish the transcribed (TS) and nontranscribed (NTS) strands of the MTIA gene. (B) Repair values calculated from scanning densitometry measurements of the hybridization signals in the autoradiogram. The mean of all six 0 time values, 0.71 ± 0.03 (SD) CPD per 10 kb, was set equal to 100%. Filled symbols represent TS; open symbols represent NTS. Circles, normal fibroblasts, GM38; squares, XP-G fibroblasts XP125LO; and triangles, XP-G/CS fibroblasts, XPCS1LV.