Fig 3. NSM mutation causes mis-localization of the SNRPE/SmE protein.

(A-B), Indirect immunofluorescence and confocal microscopy of HeLa cells transfected with either FLAG-tagged wild type or mutant SmE (WT/Mut) or left untransfected (negative control). Empty white arrowheads indicate localization pattern observed and filled white arrowheads indicate zoomed in region shown in the overly inset. (A), Top panel shows clear co-localization of wild type SmE (green) and coilin (magenta) in CBs and middle panel shows most of the mutant SmE (green) distributed in the cytoplasm with a minor fraction in the nucleus and co-localizing with coilin (magenta) in CBs. (B), While wild type SmE (green, top panel) co-localizes with SmD3 (magenta) in CBs and splicing speckles, the mutant SmE (green, middle panel) is predominantly cytoplasmic with marginal co-localization with SmD3 in CBs or in nuclear speckles.