Figure 4. Investigation into the mechanism of pp32r1-mediated FTY720 resistance. (A) Protein phosphatise 2A assay performed on ACHN cell lysates in the absence and presence of FTY720, *P < 0.05. (B) Transduced cell lysates were shown to contain overexpressed pp32r1/pp32r1Y140H (anti-V5) while endogenous pp32 protein is observed in all three lysates. Co-immunoprecipitation,with anti- HuR antibody is only able to co-immunoprecipitate endogenous pp32.