Huntingtin: alive and well and working in middle management.

A decade after the discovery of the HD gene, huntingtin is implicated in signal transduction in neuronal and nonneuronal cells. Its predicted physical properties, dynamic subcellular locations, and variable protein associations suggest that huntingtin may act to organize components of signal transduction complexes. This middle management position befits a ubiquitous, conserved protein and provides the opportunity for some subtle piece of mischief that leads eventually to a devastating inherited human disorder.