Peroxisomes: simple in function but complex in maintenance.

Peroxisomes compartmentalize part of the anabolic and catabolic pathways and reactions of the cell. Dysfunction of a single peroxisomal enzyme or loss of the whole peroxisomal compartment causes sporadic, but serious, human diseases. Genetic studies in various yeasts have identified PEX genes, which are required for the maintenance of complete peroxisomes. Mutations in PEX genes have proved to be the molecular cause of several human diseases, particularly those involving loss of organelles. Peroxisomes have several properties that distinguish them from other organelles, including the import of folded proteins from the cytosol by an unknown mechanism. By discussing recent highlights from the field of peroxisome research, we aim to share with the general readership our excitement as well as the many mysteries still surrounding peroxisome function and maintenance.