Huntingtin: Proteins and Enzymes

Huntingtin protein (Htt) is a 348 kDa protein product of Huntington's disease (HD, IT15) gene. Huntington's disease is a neurodegenerative disorder caused by a mutation on the HD gene, producing a polyglutamin (polyQ) expansion on the N-terminus of Htt. The mutant Htt leads to cytotoxicity in the striatal neuron (1). This cytotoxicity is modulated by proteolytic cleavage with caspases and calpains, producing N-terminal polyQ fragments. A phosphorylation of Htt may also regulate the cleavage and ...