Leptomycin B neither inhibits nuclear export nor degradation of the VDR.

(A) Representative Western blot of VDR, p53 and CD3ζ (loading control) in whole cell lysates of T cells activated for 3 d in the absence of 25(OH)D₃ and then treated with the indicated concentrations (ng/ml) of leptomycin B (LMB) for 4 h. (B) Relative VDR and p53 protein expression obtained from Western blot analysis of whole cell lysates from T cells treated as described in A. The density of the VDR and p53 bands were normalized to the density of the VDR and p53 bands of T cells not treated with LMB, respectively. Results are presented as mean + SEM (n = 3; * p<0.05). (C) Representative Western blot of VDR, p53 and CD3ζ (loading control) in cytoplasmic (C) and nuclear (N) fractions of T cells treated as described in A.