Determination of pbmrp transcript levels in sensitive and drug resistant P. berghei parasites. (A) Representative results of an RPA analysis using total RNA dilutions from the drug sensitive N clone or the CQ selected RC line showing protected fragments with the βtub or pbmrp riboprobes. βtub was included as a normalizing control. (B) Densitometric analysis of pbmrp expression. Densities of the normalized pbmrp signals were subsequently normalized to the drug sensitive N-clone to estimate the relative mRNA expression levels in RC. The horizontal line represents mean relative expression of four experiments.