Fig. 2.

Lens epithelial cells cultured for 5 days to allow the differentiation of lentoids, and immunostained. Nuclei are labelled with DAPI (blue). Bars = 5 µm (a and b–f). (a) A lentoid (L) surrounded by lens epithelial cells (E). The culture is stained with MitoTracker® (red) and anticytochrome oxidase (green). The cells in the differentiated lentoid contain no nuclei and do not label with MitoTracker®, but show cytochrome oxidase immunoreactivity. In the undifferentiated lens epithelial cells MitoTracker® co-localizes with cytochrome oxidase (yellow; arrow). The epithelial sheet itself is out of the plane of focus. (b) Denucleating cells in a differentiating lentoid immunostained with MitoTracker® (red) and anticytochrome oxidase (green). During the phase of nuclear shrinkage (arrow), cytochrome oxidase co-localizes with MitoTracker® (yellow). (c) Undifferentiated lens epithelial cells stained for cytochrome c (green) and cytochrome oxidase (red). The cytochrome c and cytochrome oxidase co-localize (yellow) in mitochondria. (d) A denucleating cell in a lentoid at the stage of nuclear shrinkage in a lentoid stained with MitoTracker® (red) and cytochrome c (green). The distribution of cytochrome c is diffuse and perinuclear in location. (e) A denucleating cell in a lentoid at the stage of nuclear fragmentation (arrow) stained as in d. The cytochrome c has now disappeared leaving the perinuclear mitochondria labelled red by Mitoracker®. (f) As d and e, stained for cytochrome c (red) and cytochrome oxidase. Mitochondria are located in the perinuclear region, and in one case cytochrome c co-localizes with the cytochrome oxidase labelling (yellow; arrow).