The 22kDa peroxisomal membrane protein (PMP22) is a major component of peroxisomal membranes. PMP22 seems to be involved in pore-forming activity and may contribute to the unspecific permeability of the organelle membrane. PMP22 is synthesised on free cytosolic ribosomes and then directed to the peroxisome membrane by specific targeting information []. SYM1 in yeast and Mpv17 in higher eukaryotes are closely related peroxisomal proteins required to maintain mitochondrial DNA (mtDNA) integrity and stability [, ]. Mpv17 is involved in the development of early-onset glomerulosclerosis [].Woronin sorting complex protein from Neurospora crassa is also included in this family. It is involved in both Woronin bodies (WB) formation and inherence [].
