PEX11

PEX11 refers to a family of peroxisomal membrane proteins essential for peroxisome proliferation and division in eukaryotic cells. In yeast, a single PEX11 gene encodes Pex11p that promotes peroxisome elongation and fission; in metazoans, several paralogs exist (for example PEX11A and PEX11B) that contribute to maintaining peroxisome number and morphology in a tissue- and condition-dependent manner.

Biogenesis and localization: PEX11 proteins are embedded in the peroxisomal outer membrane, typically predicted to contain two transmembrane helices with both termini facing the cytosol. They act by remodeling the peroxisomal membrane and by recruiting components of the peroxisomal fission machinery, notably the dynamin-related protein 1 (DRP1/DLP1) and accessory factors, to promote membrane scission.

Function and regulation: PEX11 activity is linked to peroxisome abundance in response to cellular metabolism. Phosphorylation and other post-translational modifications can modulate its activity, affecting the balance between peroxisome growth and division. In plants and fungi, PEX11 family proteins cooperate with other peroxins such as PEX25, PEX27, and PEX35 to regulate division.

Clinical and research aspects: Alterations in PEX11 expression or function influence peroxisome number and size, and PEX11 genes are studied in the context of peroxisomal biogenesis disorders and metabolic disease. Their function is conserved across eukaryotes, highlighting their central role in peroxisome maintenance.