Figure 4.

Dicistronic analysis of ICS2–17 and segments of this sequence. (A) Insets include one copy of selected sequence ICS2–17 (hatched bar, thin line, gray bar) and five copies of either ICS2–17.1 (hatched bars) or ICS2–17.2 (gray bars). Other Insets are as described in Fig. 3. The histogram shows normalized Photinus luciferase activities (± SEM) in transfected B104 cells. (B) Northern blot of total RNA purified from B104 cells transfected with the (ICS-2–17.2)₅/RPh dicistronic construct and probed with a Photinus luciferase riboprobe. The positions of the 28S and 18S rRNAs are indicated. (C) Complementarity between ICS2–17.2 and 18S rRNA. The upper sequence is that of the selected sequence ICS2–17.2, the lower sequence is that of rat 18S rRNA at nucleotides 68–76, with complementary nucleotides indicated by vertical lines.