The outer envelope protein OEP24 from pea chloroplasts can functionally replace the mitochondrial VDAC in yeast

The chloroplastic outer envelope protein OEP24 from pea forms a high-conduc tance low specificity solute channel as shown by in vitro studies. In order to establish its function also in an in vivo-like system, the gene encodin g OEP24 was transformed into a yeast strain which lacks the general mitocho ndria solute channel porin, also known as voltage-dependent anion channel ( VDAC), Transformation of the yeast VDAC(-) strain with the OEP24 gene resul ted in the recovery of a phenotype indistinguishable from the wild-type. Th e OEP24 pol peptide is targeted to the mitochondrial outer membrane in this heterologous system. We conclude that OEP24 forms a solute channel in pea chloroplasts in planta. (C) 1999 Federation of European Biochemical Societi es.