FIG. 8.
U2AF65 cross-linking with the RNA substrate indicated in the diagram. The 32P-labeled, in vitro-transcribed RNA transcripts were UV cross-linked in HeLa cell nuclear extract in the presence of increasing amounts of buffer alone or of GST-mHuB RRM1,2 or mHuB (50 and 200 ng) and immunoprecipitated with the anti-U2AF65 antibody. nt, nucleotides.