Fig. 5. (A-R) Sequences of time-lapse photographs to illustrate mitotic divisions in the neural rod. (A-I) The neural rod of an embryo carrying the transgenic insertions Tg(H2AF/Z)^kca37 and Tg(H2AF/Z)^kca66, surrounded by somites (som) on either side. The oblique white line in A labels the zone of apposition of the two halves of the neural anlage. The photographs show a nucleus (arrow), which is about to enter prophase. Notice that the orientation of the metaphase plate has turned by 90° at 12 minutes 45 seconds (C). The nucleus then divides within 3 minutes and 45 seconds (D), and the two daughter nuclei are incorporated into different sides of the neuroepithelium (arrows). Note that the plane of cleavage in this division, as well as in other divisions shown in the remaining photographs, is parallel to the neuroepithelium. (J-R) A mitosis at the neural rod stage of an embryo that expresses tau:GFP. The arrows in J and L indicate the centrosome before and after division, those in M-P indicate the plane of rotation. Anterior is towards the top in all photographs.