  We study a four-dimensional effective theory of the five-dimensional (5D)
gauged supergravity with a universal hypermultiplet and perturbative
superpotential terms at the orbifold fixed points. Among eight independent
isometries of the scalar manifold, we focus on three directions for gauging by
the graviphoton. The class of models we consider includes the 5D heterotic
M-theory and the supersymmetric Randall-Sundrum model as special limits of the
gauging parameters. We analyze the vacuum structure of such models, especially
the nature of moduli stabilization, from the viewpoint of the effective theory.
We also discuss the uplifting of supersymmetric anti-de Sitter vacua.
