Fig. 4. A-type lamin is essential for targeting of proAR to the nuclear envelope. (A) HeLa cells were transfected with 20 nM or 50 nM of lamin A/C-targeting duplex siRNA (si-lamin A/C) or control siRNA (si-control). After 72 hours, the cells lysates were analyzed by western blotting with anti-lamin A/C mAb or anti-lamin B pAb. (B) HeLa cells were transfected twice: first with 20 nM of control siRNA (upper) or lamin A/C-siRNA (lower); and, after 48 hours, with wild-type AREG plasmid. After 24 hours, cells were stimulated with or without TPA, and then fixed. Cells were stained with anti-AR-C pAb and anti-lamin A/C mAb. The lower panels (1 and 2) are high magnification images of the boxed areas above. Scale bars: 5 µm.