Supplemental Materials

This article contains the following supporting material:

• Supplemental Figure 1 - YFP-PSP1 signal in perinucleolar cap structures during telophase. Fluorescent micrographs of selected 2D projections of the 3D stacks that were acquired over the over the course of 3 hours of live cell imaging of a representative HeLa^YFP-PSP1α cell, with particular emphasis on images captured during telophase. Scale bar, 10 μm. Arrowheads label the transient perinucleolar cap structures and these are shown in greater detail in the insets. Arrows indicate the newly forming paraspeckles.
• Supplemental Figure 2 - Localisation of YFP-PSP1 mutants following treatment with ActD. Representative fluorescent micrographs of HeLa cells that were transfected with the YFP-PSP1 mutant constructs listed in Figure 4 and subsequently incubated with the RNA Polymerase II transcription inhibitor, Actinomycin D (see methods). Arrowheads indicate perinucleolar caps. Blue – DAPI, Green – YFP signal. Red – Pyronin Y (total RNA signal) Scale bar, 10 μm.
• Video 1 - Transcription inhibition by DRB treatment prolongs the appearance of perinucleolar YFP-PSP1 in newly divided cells, with paraspeckles only reappearing once the drug is removed
• Video 2 - YFP-PSP1 through the cell cycle