Characterization and localization of the Huntington disease gene product

The recent identification of the Huntington's disease (HD) gene,enabled us to synthesize oligopeptides corresponding with thecarboxy-terminal end of the predicted HD-gene (IT15) product.Immunobiochemical studies with polyclonal antibodies directedagainst this synthetic peptide (position 3114–3141) onlymphobiastold cells from normal individuals and patients withHuntington disease, revealed the presence of a protein (huntingtin)with a molecular mass of approximately 330 kDa. Immunocytochemicalstudies showed a cytoplasmic localization of huntingtin in variouscell types including neurons. In most of the neuronal cellsthe protein was also present in the nucleus. No difference inmolecular mass or intracellular localization was found betweennormal and mutant cells.