Huntingtin acts in the nucleus to induce apoptosis but death does not correlate with the formation of intranuclear inclusions

Cell. 1998 Oct 2;95(1):55-66. doi: 10.1016/s0092-8674(00)81782-1.

Abstract

The mechanisms by which mutant huntingtin induces neurodegeneration were investigated using a cellular model that recapitulates features of neurodegeneration seen in Huntington's disease. When transfected into cultured striatal neurons, mutant huntingtin induces neurodegeneration by an apoptotic mechanism. Antiapoptotic compounds or neurotrophic factors protected neurons against mutant huntingtin. Blocking nuclear localization of mutant huntingtin suppressed its ability to form intranuclear inclusions and to induce neurodegeneration. However, the presence of inclusions did not correlate with huntingtin-induced death. The exposure of mutant huntingtin-transfected striatal neurons to conditions that suppress the formation of inclusions resulted in an increase in mutant huntingtin-induced death. These findings suggest that mutant huntingtin acts within the nucleus to induce neurodegeneration. However, intranuclear inclusions may reflect a cellular mechanism to protect against huntingtin-induced cell death.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Apoptosis*
  • Brain-Derived Neurotrophic Factor / metabolism
  • Cell Nucleus / metabolism
  • Cells, Cultured
  • Ciliary Neurotrophic Factor
  • Huntingtin Protein
  • Inclusion Bodies*
  • Mutagenesis
  • Nerve Degeneration
  • Nerve Tissue Proteins / genetics
  • Nerve Tissue Proteins / metabolism*
  • Neurons / cytology
  • Nuclear Proteins / genetics
  • Nuclear Proteins / metabolism*
  • Peptides / metabolism
  • Rats
  • Transgenes

Substances

  • Brain-Derived Neurotrophic Factor
  • Ciliary Neurotrophic Factor
  • Htt protein, rat
  • Huntingtin Protein
  • Nerve Tissue Proteins
  • Nuclear Proteins
  • Peptides
  • polyglutamine