FIG. 5.
vhs synthesized in a HeLa cell translation extract induces degradation of SRPα RNA. (A) HeLa cell translation extracts and RRL were programmed with capped unlabeled vhs RNA, and translation was allowed to proceed for 60 min in the presence of [35S]methionine. Extracts were then challenged with cap-labeled SRPα RNA, and samples were recovered at the indicated times (minutes). Reaction products were then analyzed by agarose-formaldehyde gel electrophoresis as in Fig. 1B. The bottom of panel A shows an overexposure of the lower portion of the membrane in panel A (indicated by an arrow). Lane control, HeLa cell extracts lacking vhs RNA. Numbers to the left of panel A indicate the sizes of RNA markers (lane M) in nucleotides. Solid arrowheads indicate the positions of vhs-induced RNA degradation products. (B) Samples of the translation reaction products used in panel A were resolved on an SDS–12% polyacrylamide gel, and the 35S signal was detected by autoradiography.