Movie 2.

Ectopic lumens form de novo. MDCK cysts were induced at day 3 to express EREG-EGFP or (Y156A)EREG-EGFP as indicated and followed over the next 3 days by live cell imaging. Confocal images at the equatorial plane were taken every 40 min for EGFP (green) and Brightfield channels. All images were taken over 3 days were stitched into a single video and displayed here. Scale bars: 50 μm.