Figure 1.

Protein traffic to the peroxisome. Under the old model (Lazarow and Fujiki 1985), peroxisomal membrane proteins (PMPs) target to the organelle after translation on cytosolic ribosomes. Recent evidence, however, argues that PMPs are first inserted into the endoplasmic reticulum (ER) via either the Sec61 translocon or the GET (Get1p/Get2p/Get3p) complex. Subsequently, the PMPs exit the ER to reach the peroxisome. There is consensus in the literature that peroxisomal matrix proteins target to the organelle after translation on cytosolic ribosomes.