Previously Unknown Protein Contributes to Huntington Disease

A mutant form of a protein called huntingtin (mHtt) is central to the corpus striatum and cerebral cortex pathology seen in patients with Huntington disease (HD). The soluble form of mHtt is neurodestructive, whereas aggregates of mHtt might be neuroprotective. Investigators have long suspected that mHtt is not the sole explanation for HD, because mHtt is expressed throughout the brain, and most of the brain is unaffected by the disease.

A team from Johns Hopkins has identified a protein, called Rhes, that acts as an important cofactor in producing HD pathology. Rhes is expressed predominantly in the corpus striatum and, to a lesser extent, in the cerebral cortex. Rhes raises the concentration of the soluble form of mHtt, leading to neuronal…