Taz1, an Outer Mitochondrial Membrane Protein, Affects Stability and Assembly of Inner Membrane Protein Complexes: Implications for Barth Syndrome

• DOI: 10.1091/mbc.e05-03-0256
• Publication Date: 2005-09-01T00:14:17Z
• Authors: Katrin Brandner; David U. Mick; Ann E. Frazier; Rebecca D. Taylor; Chris Meisinger; Peter Rehling
• Keywords: Translocase; Intermembrane space

The Saccharomyces cerevisiae Taz1 protein is the orthologue of human Tafazzin, a that when inactive causes Barth Syndrome (BTHS), severe inherited X-linked disease. mitochondrial acyltransferase involved in remodeling cardiolipin. We show an outer membrane exposed to intermembrane space (IMS). Transport into mitochondria depends on receptor Tom5 translocase (TOM complex) and small Tim proteins IMS, but independent sorting assembly complex (SAM). TAZ1 deletion yeast leads growth defects nonfermentable carbon sources, indicative defect respiration. Because cardiolipin has been proposed stabilize supercomplexes respiratory chain complexes III IV, we assess taz1delta these are destabilized taz1Delta mitochondria. This selective release IV monomer from III2IV2 supercomplex. In addition, analyses newly imported subunits incorporation affected conclude inactivation affects both stability inner