Oxa1 Superfamily: New Members Found in the ER

Oxa1/Alb3/YidC family members promote the insertion of proteins into the mitochondrial inner membrane, the chloroplast thylakoid membrane, and the bacterial plasma membrane. Remarkably, two recent studies identify new Oxa1 homologs that reside in the endoplasmic reticulum (ER) and function in ER membrane protein biogenesis.