Figure 5. Lin28 and IMP associate with upd RNAs. (A) qRT-PCR showing the relative levels of Luc-Upd3’UTR reporters in cells co-transfected in the presence and absence of Lin28, showing increased Luc-Upd reporter expression in presence of lin28. Site directed mutagenesis of the Lin28 binding GGAGA motif abolishes the stabilization induced by Lin28 expression. (B and C) RNA-immunoprecipitation performed on S2 cells transfected with HA-tagged Lin28 and Flag-tagged IMP. Immunoprecipitation followed by RT-PCR detects that IMP and Lin28 immunoprecipitants contain upd RNAs. Depletion of either Lin28 or IMP does not affect RNA binding of the other protein. (D) Quantification of RNA-immunoprecipitation. siControl: scrambled siRNA. * denotes P<0.05, ** denotes P<0.01, *** denotes P<0.001.