Sam68 localizes in nuclear bodies. (A) Anti-Sam68 AD1 recognizes Sam68 but not SLM-1 and SLM-2. HeLa cells transfected with GFP alone, GFP-Sam68, GFP-SLM-1, or GFP-SLM-2 were lysed and the cell lysates were divided equally, resolved by SDS-PAGE, transferred to nitrocellulose membranes, and immunoblotted with anti-Sam68 C-20 (lanes 1–4) or AD1 (lanes 5–8) antibodies. The migration of endogenous and GFP-Sam68/SLM proteins is indicated on the right, and the positions of molecular mass markers (in kilodaltons) are shown on the left. (B) HeLa cells were fixed, permeabilized, and immunostained with anti-Sam68 mAb 7-1, rabbit polyclonal Sam68/SLM C-20 antibody, rabbit polyclonal antibody AD1, or normal rabbit serum (NRS), followed by a rhodamine-conjugated goat anti-mouse or anti-rabbit secondary antibody, and visualized by fluorescence microscopy. Expression vectors encoding GFP-Sam68 or GFP alone were transfected into HeLa cells, and 12 h after transfection, live cells were visualized by fluorescence microscopy.