Insights into ATP synthase assembly and function through the molecular genetic manipulation of subunits of the yeast mitochondrial enzyme complex

Development of an increasingly detailed understanding of the eucaryotic mit ochondrial ATP synthase requires a detailed knowledge of the stoichiometry, structure and function of F-0 sector subunits in the contexts of the proto n channel and the stator stalk. Still to be resolved are the precise locati ons and roles of other supernumerary subunits present in mitochondrial ATP synthase complexes, but not found in the bacterial or chloroplast enzymes. The highly developed system of molecular genetic manipulation available in the yeast Saccharomyces cerevisiae, a unicellular eucaryote, permits testin g for gene function based on the effects of gene disruption or deletion. In addition, the genes encoding ATP synthase subunits can be manipulated to i ntroduce specific amino acids at desired positions within a subunit, or to add epitope or affinity tags at the C-terminus, enabling questions of stoic hiometry, structure and function to be addressed. Newly emerging technologi es, such as fusions of subunits with GFP are being applied to probe the dyn amic interactions within mitochondrial ATP synthase, between ATP synthase c omplexes, and between ATP synthase and other mitochondrial enzyme complexes . (C) 2000 Elsevier Science B.V. All rights reserved.