Fig. 6. Gomafu RNA escapes nuclear export. Gomafu RNA (green) and NLS-EGFP (magenta) were simultaneously detected in three independent heterokaryons consisting of three (A-A'''), four (B-B''') or five (C-C''') nuclei, respectively. In all the cases, NLS EGFP shuttled between the cytoplasm and nucleus and thus was observed in every nucleus of the heterokaryon (A',B',C'), whereas Gomafu RNA was detected only in the nucleus expressing this gene (A'',B'',C''; arrowheads). DAPI-stained nuclei of the heterokaryon are shown in A-C. The images were obtained using a conventional epifluorescent microscope. (D) Northern blot analysis of Gomafu RNA and mature product of UHG (U22 snoRNA host gene). Note that cytoplasmic UHG was stabilized upon inhibition of NMD by the cycloheximide treatment, whereas no change was observed in the amount of cytoplasmic (Cyto) Gomafu RNA. Bars, 5 µm.