FIGURE 2:

MRP RNA coprecipitates with CUGBP and PTB. (A) RNA pull-down assays were completed in PC3M and HeLa cells using a TH12 oligo specific for MRP RNA and scrambled TH12 oligo and beads-alone controls, and RT-PCR was utilized to amplify MRP and TRAF RNAs. (B) Anti-CUGBP and anti-PTB antibodies were used to detect proteins from RNA pull-down assays in HeLa cells. (C) HeLa cell lysates were subjected to IP using anti-PTB, anti-CUGBP, and anti-IgG antibodies and analyzed by RT-PCR for MRP and U3 RNA, (D) or Western blot with an anti-CUGBP antibody, (E) and under cross-linking conditions. (Fi) CUGBP and (Fii) MRP RNA are precipitated in α-amanitin–treated HeLa cells. (Gi) HeLa and WI-38 cells were immunoprecipitated with PTB or beads alone and analyzed by RT-PCR. In lanes 2 and 5 PTB is precipitated and U3 RNA is amplified, and in lanes 3 and 6 MRP RNA is amplified. (Gii) PTB protein was precipitated from HeLa and WI-38 cells and blotted with anti-PTB.