Figure 3.
Determination of minimal size requirement for RNA–La protein interaction. U6 and B2 RNAs were transcribed from plasmid DNA templates in the absence of ATP to generate abortive transcripts. Immunoprecipitation of these short oligonucleotides containing 5′ ppp was performed using Hela cell extracts or recombinant La protein, as described in Materials and Methods. Bound RNAs for B2 (lanes 2–3) and U6 (lanes 4–5) were fractionated along with the starting material and visualized by autoradiography.