Huntingtin regulates RE1-silencing transcription factor/neuron-restrictive silencer factor (REST/NRSF) nuclear trafficking indirectly through a complex with REST/NRSF-interacting LIM domain protein (RILP) and dynactin p150 Glued

J Biol Chem. 2008 Dec 12;283(50):34880-6. doi: 10.1074/jbc.M804183200. Epub 2008 Oct 15.

Abstract

Huntingtin has been reported to regulate the nuclear translocation of the transcriptional repressor RE1-silencing transcription factor/neuron-restrictive silencer factor (REST/NRSF). The REST/NRSF-interacting LIM domain protein (RILP) has also been shown to regulate REST/NRSF nuclear translocation. Therefore, we were prompted to address the question of how two distinct proteins could have the same function. We initially used a yeast two-hybrid screen to look for an interaction between huntingtin and RILP. This screen identified dynactin p150(Glued) as an interacting protein. Coimmunoprecipitation of proteins in vitro expressed in a reticulocyte lysate system showed an interaction between REST/NRSF and RILP as well as between RILP and dynactin p150(Glued). Coimmunoprecipitation analysis further showed a complex containing RILP, dynactin p150(Glued), and huntingtin. Huntingtin did not interact directly with either REST/NRSF or RILP, but did interact with dynactin p150(Glued). The N-terminal fragment of wild-type huntingtin did not affect the interaction between dynactin p150(Glued) and RILP; however, mutant huntingtin weakened this interaction. We further show that HAP1 (huntingtin-associated protein-1) prevents this complex from translocating REST/NRSF to the nucleus. Thus, this study suggests that REST/NRSF, dynactin p150(Glued), huntingtin, HAP1, and RILP form a complex involved in the translocation of REST/NRSF into the nucleus and that HAP1 controls REST/NRSF cellular localization in neurons.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Active Transport, Cell Nucleus
  • Adaptor Proteins, Signal Transducing / metabolism*
  • Cell Line, Tumor
  • Cell Nucleus / metabolism*
  • Dynactin Complex
  • HeLa Cells
  • Humans
  • Huntingtin Protein
  • Microscopy, Fluorescence
  • Microtubule-Associated Proteins / metabolism*
  • Nerve Tissue Proteins / chemistry*
  • Nerve Tissue Proteins / metabolism*
  • Nuclear Proteins / chemistry*
  • Nuclear Proteins / metabolism*
  • Protein Structure, Tertiary
  • Protein Transport
  • Repressor Proteins / metabolism*
  • Transcription Factors / metabolism*
  • Transcription, Genetic*

Substances

  • Adaptor Proteins, Signal Transducing
  • DCTN1 protein, human
  • Dynactin Complex
  • HAP1 protein, human
  • HTT protein, human
  • Huntingtin Protein
  • Microtubule-Associated Proteins
  • Nerve Tissue Proteins
  • Nuclear Proteins
  • RE1-silencing transcription factor
  • RILP protein, human
  • Repressor Proteins
  • Transcription Factors