PEX1
PEX1 is a member of the AAA ATPase family, a large group of ATPases associated with diverse cellular activities. This protein is cytoplasmic but is often anchored to a peroxisomal membrane where it forms a heteromeric complex and plays a role in the import of proteins into peroxisomes and peroxisome biogenesis. Mutations in this gene have been associated with complementation group 1 peroxisomal disorders such as neonatal adrenoleukodystrophy, infantile Refsum disease, and Zellweger syndrome.
Function
Required for stability of PEX5 and protein import into the peroxisome matrix. Anchored by PEX26 to peroxisome membranes, possibly to form heteromeric AAA ATPase complexes required for the import of proteins into peroxisomes.
Biological Process
Microtubule-based peroxisome localizationManual Assertion Based On ExperimentIMP:UniProtKB
Peroxisome organizationManual Assertion Based On ExperimentIMP:UniProtKB
Protein import into peroxisome matrixManual Assertion Based On ExperimentIMP:UniProtKB
Protein targeting to peroxisomeManual Assertion Based On ExperimentIMP:UniProtKB
Involvement in disease
Peroxisome biogenesis disorder complementation group 1 (PBD-CG1):
A peroxisomal disorder arising from a failure of protein import into the peroxisomal membrane or matrix. The peroxisome biogenesis disorders (PBD group) are genetically heterogeneous with at least 14 distinct genetic groups as concluded from complementation studies. Include disorders are: Zellweger syndrome (ZWS), neonatal adrenoleukodystrophy (NALD), infantile Refsum disease (IRD), and classical rhizomelic chondrodysplasia punctata (RCDP). ZWS, NALD and IRD are distinct from RCDP and constitute a clinical continuum of overlapping phenotypes known as the Zellweger spectrum (PBD-ZSS).
Peroxisome biogenesis disorder 1A (PBD1A):
A fatal peroxisome biogenesis disorder belonging to the Zellweger disease spectrum. PBD1A is an autosomal recessive systemic disorder characterized clinically by severe neurologic dysfunction with profound psychomotor retardation, severe hypotonia and neonatal seizures, craniofacial abnormalities, liver dysfunction, and biochemically by the absence of peroxisomes. Additional features include cardiovascular and skeletal defects, renal cysts, ocular abnormalities, and hearing impairment. Most severely affected individuals with the classic form of the disease (classic Zellweger syndrome) die within the first year of life.
Peroxisome biogenesis disorder 1B (PBD1B):
A peroxisome biogenesis disorder that includes neonatal adrenoleukodystrophy (NALD) and infantile Refsum disease (IRD), two milder manifestations of the Zellweger disease spectrum. The clinical course of patients with the NALD and IRD presentation is variable and may include developmental delay, hypotonia, liver dysfunction, sensorineural hearing loss, retinal dystrophy and vision impairment. Children with the NALD presentation may reach their teens, while patients with the IRD presentation may reach adulthood. The clinical conditions are often slowly progressive in particular with respect to loss of hearing and vision. The biochemical abnormalities include accumulation of phytanic acid, very long chain fatty acids (VLCFA), di- and trihydroxycholestanoic acid and pipecolic acid.
Heimler syndrome 1 (HMLR1):
A form of Heimler syndrome, a very mild peroxisome biogenesis disorder characterized by sensorineural hearing loss, amelogenesis imperfecta resulting in enamel hyoplasia of the secondary dentition, nail defects, and occasional or late-onset retinal pigmentation abnormalities.