ER tubule-shaping proteins delay NE formation. U2OS cells were transfected with GFP-NLS and H2B-tdTomato (control), with V5-tagged ER-shaping protein (Rtn3, Rtn4, or DP1), or with the V5-tagged ER protein Sec61β, then NE formation was analyzed. (A) Representative traces of nuclear GFP-NLS intensity during NE formation are shown. (B) Mean times from chromosome segregation to the onset of nuclear accumulation are plotted with standard error bars.