Fig. 6. Confocal laser scanning microscope image of double-immunofluorescence assay using anti-Alrp (green) and anti-CoxVb (mitochondrial subunit Vb of cytochrome oxidase) (red). The highest levels of Alrp are observed in spermatogonia and elongated sperm cells, whereas the highest levels of CoxVb are found in other cells. The yellow colour therefore indicates that co-localisation of Alrp and CoxVp inside mitochondria occurs only when approximately equal amounts of the two proteins are present. Scale bar, 50 µm.