2012/12/01 by Thomas D. Fox · 1 citation
Biochemistry, Genetics and Molecular Biology · #Mitochondrial Function and Pathology #Photosynthetic Processes and Mechanisms #ATP Synthase and ATPases Research #Intermembrane space #Translocase of the inner membrane #Translocase of the outer membrane #Biology #Cell biology #Mitochondrial intermembrane space #Inner membrane #Mitochondrial membrane transport protein #Organelle #Mitochondrial carrier #Inner mitochondrial membrane #Cytoplasm #Protein targeting #Membrane protein #Mitochondrion #Bacterial outer membrane #Biochemistry #Membrane #Gene
paper · pdf · doi:10.1534/genetics.112.141267
openalex publication_date 2012/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/21
The mitochondrion is arguably the most complex organelle in the budding yeast cell cytoplasm. It is essential for viability as well as respiratory growth. Its innermost aqueous compartment, the matrix, is bounded by the highly structured inner membrane, which in turn is bounded by the intermembrane space and the outer membrane. Approximately 1000 proteins are present in these organelles, of which eight major constituents are coded and synthesized in the matrix. The import of mitochondrial proteins synthesized in the cytoplasm, and their direction to the correct soluble compartments, correct membranes, and correct membrane surfaces/topologies, involves multiple pathways and macromolecular machines. The targeting of some, but not all, cytoplasmically synthesized mitochondrial proteins begins with translation of messenger RNAs localized to the organelle. Most proteins then pass through the translocase of the outer membrane to the intermembrane space, where divergent pathways sort them to the outer membrane, inner membrane, and matrix or trap them in the intermembrane space. Roughly 25% of mitochondrial proteins participate in maintenance or expression of the organellar genome at the inner surface of the inner membrane, providing 7 membrane proteins whose synthesis nucleates the assembly of three respiratory complexes.