Consequence of Mutant RPL13 on Pre-rRNA Processing
(A) Northern blot analysis of pre-RNAs in HeLa cells treated with RPL13 siRNAs. The 5′ITS1 and the ITS2 probes detect the precursors to the 40S and 60S subunit RNAs, respectively. The ITS1-5.8S probe evidences accumulation of 36S and 36S-C precursors, indicative of a defect in cleavage at site 2.
(B) Northern blot analysis of pre-rRNAs from fibroblasts of individual P1, lymphoblastoid cells of individual P2, and healthy donors with the same probes as in (A).
(C) Quantification of changes in the pre-rRNA pattern in (A) and (B) by ratio analysis of multiple precursors (RAMP)(27), expressed as variations relative to the respective controls (number of replicate are stated in the figure). The analysis shows no significant variation in individual cells, unlike in RPL13 siRNA-treated cells.