FIG. 4.

Deadenylation during maturation does not result in decapping. L1-A₃₀ RNA was either uniformly labeled by using [α-³²P]UTP during transcription in vitro (odd numbered lanes) or labeled exclusively in its cap structure as depicted in Fig. 1 (even numbered lanes). Samples were taken immediately following microinjection (lanes 1 and 2) or after 20 h in the absence (lanes 3 and 4) or presence (lanes 5 and 6) of progesterone.