FIG. 1.

Stabilization of the nonsense TSD mRNA with cycloheximide. (Top) Northern blot analysis of total RNA isolated from lymphoblasts, either normal (lanes 1 and 2) or TSD (lanes 3 and 4), with and without a 4-h cycloheximide treatment. (Bottom) PhosphorImager quantitation of the average amount of HEXA mRNA in the above lanes and in two other experiments, normalized to β-actin. Error bars indicate standard deviations. The mRNA measured is the major species of 2.1 kb. The two minor species (2.4 [∗] and 2.6 [∗∗] kb, respectively) are described in the text.