Figure 1. The levels of RBP NF90 are lower in senescent cells.
(A) Western blot analysis of the expression levels of RBPs HuR, AUF1, NCL and NF90 in whole-cell lysates prepared from human diploid WI-38 fibroblasts ['young', proliferating (P, pdl 20) or senescent (S, pdl 54)] and from human IDH4 fibroblasts [P (+Dex) or S (-Dex for 9 days)]; the levels of GAPDH were assessed as a loading control. (B) Western blot analysis of the senescence-associated cdk inhibitor p21 in cells from the populations described in panel A. (C,D) In the WI-38 (C) and IDH4 (D) cell populations described in panel A, total RNA was prepared and the levels of mRNAs encoding the SASP factors shown were measured by RT-qPCR. Data are the means and standard deviation (+SD) from three independent experiments.