The 70 kDa peroxisomal membrane protein: an ATP-binding cassette transporter protein involved in peroxisome biogenesis

The 70 kDa peroxisomal membrane protein (PMP70) is a major component of peroxisomal membranes. cDNAs for human and rat PMP70 have been cloned and sequenced and the gene mapped to the human chromosome 1p21-22. The predicted amino acid sequence showed homology to members of the ATP-binding cassette transporter family. In humans, mutations in the PMP70 gene have been found in a subset of patients with Zellweger syndrome, a lethal inborn error of peroxisome biogenesis. These results suggest that PMP70 functions in transporting molecules or possibility peptides across the peroxisomal membrane and has an important role in peroxisome assembly.