Involved in peroxisomal proliferation. May regulate peroxisome division by recruiting the dynamin-related GTPase DNM1L to the peroxisomal membrane. Promotes membrane protrusion and elongation on the peroxisomal surface. Homodimer. Heterodimer with PEX11G. Interacts with PEX19. Interacts with FIS1. Mice have a marked decrease in peroxisome abundance. They share several phenotypes with Zellweger syndrome mouse models, including neuronal migration defects, hypotonia, a developmental delay, and neonatal lethality but no detectable defect in peroxisomal protein import and only mild defects in peroxisomal metabolic function. Belongs to the peroxin-11 family.