Movie 1

Asymmetric division of lineage-traced a-tanycytes and migration of their daughters into the hypothalamic parenchyma ex vivo.
Movie compilation of single images obtained from the brain of a tamoxifen pulsed P4/P5 mouse, analysed at P12 ex vivo. Movie shows independent and asynchronous cell divisions by Tom⁺ lineagetraced α-tanycytes. Ventricular walls at the left of the image. Note, the lateral migration of one daughter using the radial process of the parent cell, followed by another cell division and further lateral migration of the second daughter into the hypothalamic parenchyma. Event time: 32 hours. Movie is representative of similar events observed in separate experiments and slices as well as lineage tracing studies in vivo (Fig. 5 E,F,H).