Figure 3

Skin surface exoribonuclease activity. Analysis of degradation fragments by Northern Blot. Capped β-galactosidase (lacZ, ~3, 5 kb) encoding mRNA was digested for the indicated time by ribonucleases from Homo sapiens hand surface (final dilution 4×) and detected by a probe binding close to the 5'-end (in A and B) or after stripping of the blot by a probe binding close to the 3'-end (in C and D) of the mRNA. The densitograms of bound radioactivity for the highlighted lanes (0' and 20') of the gels (A and C) are shown in the graphs (B and D). PSL means "photo-stimulated luminescence". Percent values given in B and D are the amount of radioactivity bound by fragments smaller than 0, 5 kb (filled area in B and D) compared to the activity bound by all fragments (filled and open area in B and D).