Monkey Kidney Cells with mEmerald-PMP and mApple-ER
Recent studies have challenged the original model for peroxisome biogenesis, which asserts that new peroxisomes develop from the fission of pre-existing ones and that peroxisomal membrane and matrix proteins are drafted straight from the cytosol. It is now suggested that some peroxisomal membrane proteins may travel from the endoplasmic reticulum to peroxisomes.
The endoplasmic reticulum was visualized in the African green monkey kidney cells (CV-1 line) featured in this digital video with mApple fused to an ER targeting signal. A red member of the mFruit series of fluorescent proteins, mApple matures rapidly and exhibits excitation and emission maxima at 568 and 592 nanometers, respectively. The CV-1 fibroblast cells were additionally labeled for peroxisomes with the green fluorescent protein mEmerald fused to a peroxisomal membrane protein targeting signal. mEmerald is a variant of enhanced GFP with improved brightness and photostability. Excitation and emission maxima of mEmerald occur at 487 nanometers and 509 nanometers, respectively.