Fig. 8. (i) Confocal sections of HeLa cells transfected with YFPSmB and treated with LMB 16 hours after transfection (A-H) or cultured in the absence of LMB (I-L). YFPSmB is seen in nuclear bodies in cells treated with LMB (arrows in C,G), but not in speckles. These nuclear bodies contain SMN (arrows in F), but do not contain p80-coilin, which is seen in the nucleolus (arrowheads in A and E). In cells incubated in the absence of LMB, YFPSmB (K) is seen to co-localize with endogenous Sm proteins (J) in Cajal bodies (arrows in I-L) and speckles (arrowheads in I-L). Bar, 10 µm. (ii) Immonoprecipitation of snRNPs from cells transfected with GFPSmD1, incubated overnight, then incubated for 16 hours in the presence (A) or absence (B) of LMB using anti-TMG antibodies, detected using anti-GFP antibodies (top panels). GFPSmD1 (lower band) is seen in the bound fraction in LMB treated cells and in control cells. The lower panels show 3D projections of serial confocal sections through cells treated with LMB (A) and control cells (B). In LMB-treated cells, GFP-SmD1 signal shows localizations characteristic of early time points after transfection, with diffuse signal and accumulation in Cajal bodies but not speckles. In control cells (B), GFPSmD1 shows a speckled localization.