Ozz:: A new name on the long list of β-catenin's nemeses

In the February issue of Developmental Cell, Nastasi et al. describe Ozz, a muscle-specific ubiquitin ligase adaptor that regulates myofibril organization. Ozz appears to function in ubiquitination and degradation of membrane-bound, but not cytosolic, β-catenin, whose turnover may be required for alignment and growth of the sarcomere, the basic contractile unit of myofibers.