Detailed changes in nuclear morphology during retinal development. A high temporal resolution (3 minutes per frame), 2-photon image series demonstrating periodic changes in nuclear morphology during apical/basal movements. (A) A highly motile nucleus demonstrating advancing movement. Red arrowheads indicate the emergence of wisp-like protrusions in the otherwise smooth apex of an H2B-GFP expressing nucleus. (B) Immotile nuclei imaged over a 153 minute time course. Yellow arrowhead indicates a relatively static nuclear morphology exhibited by what appears to be a differentiated cell. Outline (inset in i. and ii.) depicts a rapid morphological shift from progenitor-like, to a more differentiated nuclear appearance.