FIG. 4.

In vivo RNA binding by wild-type (WT) ICP27 and ICP27 mutants at two RNA binding motifs. RSFs were infected with HSV-1 KOS, tsLG4, and d4-5 at 39.5°C for 6 h, at which time infected cell monolayers were UV irradiated as described previously (58). Nuclear extracts were prepared, and RNA bound to ICP27 was isolated by immunoprecipitation with anti-ICP27 antibody H1119. (A) ICP27-bound and unbound RNA fractions were hybridized to antisense RNA probes for ICP27, gB, and gD transcripts as described previously (58). (B) ICP27-bound RNA fractions were fractionated on SDS-polyacrylamide gels and transferred to nitrocellulose. The blots were probed with anti-ICP27 antibody.