ATP3 encodes the gamma subunit of mitochondrial F₁-ATP synthase complex (1). The F₀-F₁ATP synthase complex utilizes proton motive force for ATP hydrolysis/synthesis (2). The structure of this enzyme complex is highly conserved among diverse organisms and consists of two major components, soluble F₁ and membrane-bound F₀, each of which contains many subunits. F₁ and F₀ are connected, both functionally and physically, via two additional multi-subunit structures, the central stalk and the stator stalk. The gamma subunit is a component of the central stalk. The central stalk functions like a rotor shaft to transmit the movement of the F₀ proton pump to the catalytic core of F₁. Although the gamma subunit is not specifically required for F₁ ATPase activity, it is essential for enzyme complex cooperativity (2 and 3 and references therein).

ATP3 is essential for ATP synthase function, but it is not essential for life in yeast. Deletion of ATP3, like deletions in many genes necessary for the function or maintenance of mitochondria, leads to a "petite" phenotype that is slow-growing and unable to survive on nonfermentable carbon sources (1).

General ATP synthase structure and function are reviewed in references 2 and 3. For a review that is specific to yeast, see reference 4.

Last updated: 2001-01-11