Effect of ATRA treatment on the SERCA expression of fresh APL cells. Freshly isolated APL blasts were treated by 0.1 μmol/L ATRA over 7 days and SERCA expression; cell differentiation was also determined. (A) Immunoblot analysis of SERCA 2b and SERCA_PLIM expression. (B) Modulation of SERCA expression upon ATRA treatment. One hundred percent refers to SERCA expression levels in untreated cells. (▪) SERCA_PLIM; (□) SERCA 2b. Treatment resulted in a marked induction of SERCA_PLIMexpression. (Inset) The percentage of NBT-positive cells after ATRA treatment.