Hansenula polymorpha cells lacking the ER-localized peroxins Pex23 or Pex29 show defects in mitochondrial function and morphology.

Pex23 family proteins localize to the endoplasmic reticulum and play a role in peroxisome and lipid body formation. The yeast Hansenula polymorpha contains four members: Pex23, Pex24, Pex29 and Pex32. We previously showed that loss of Pex24 or Pex32 results in severe peroxisomal defects, caused by reduced peroxisome-endoplasmic reticulum contact sites.