Peroxisomal Biogenesis Factor 19 (PEX19)

The covalent attachment of prenyl lipids, such as farnesyl or geranylgeranyl groups, by specific transferases is indispensable for the cellular sorting of many proteins.Human PEX19 expression also restored peroxisomal protein import in fibroblasts from a patient with Zellweger syndrome of CG-J. This patient was found to be homozygous for an inactivating mutation, a 1-bp insertion . These results demonstrated that PEX19 is the causative gene for CG-J PBD and suggested that the C-terminal part of the PEX19 protein, including the CAAX homology box, is required for its biologic function. Moreover, the PEX19 protein is apparently involved in the initial stage of peroxisome membrane assembly, before the import of matrix protein.