Peroxisomes Labeled with EGFP
Peroxisomes are relatively small organelles found in eukaryotic cells that are round in shape, and several hundred may occupy a single cell. The peroxisome is contained in a protective membrane of proteins and lipids, and the interior lumen contains oxidation enzymes. It is thought that peroxisomes slowly evolved due to pressures brought about by the increase of oxygen in the environment. Like mitochondria, peroxisomes are self-replicating. Though peroxisomes resemble lysosomes, they have a crystalline structure and are not formed in the Golgi apparatus. In the digital videos presented above, human cervical carcinoma (HeLa line) epithelial cells labeled with a chimera of EGFP fused to a peroxisomal targeting signal (PST1) is used to track the mobility of peroxisomes in the cytoplasm.