FIG. 3.

Primer extension of the p18(L) transcript. Total RNA was prepared from C2C12 cells cultured in growth medium (Proliferating) and C2C12 cells cultured in differentiation medium for 4 days (Differentiated). Yeast tRNA was used as a negative control. Thirty micrograms of each RNA sample was hybridized with an antisense primer specific to the p18(L) transcript, primer L, and extended with reverse transcriptase. The extension products were resolved on a 7% urea denaturing gel. The marker lane is pUC18 digested with HpaII and 5′ end labeled. The fragment lengths (in nucleotides) are indicated on the left.