FIG. 4.

UV cross-linking of cell lysates (A) and recombinant GST-hnRNP type A/B proteins (B) with various MHV RNAs. Six different RNA species, i.e., MHV minus-strand leader [(−)Leader] and its mutant lacking the four UCUAA repeats [(−)Δ4R], plus-strand leader [(+)Leader], and the minus-strand intergenic region [(−)IG] and two of its mutants [(−)MG and (−)MGG], were UV cross-linked with 30 μg of whole-cell extract (A) or 10 ng of E. coli-expressed GST-hnRNP A/B proteins (B). The arrow in panel A identifies hnRNP A1-like proteins. The arrowhead identifies PTB. Sizes are shown in kilodaltons.