Regulation of the localisation and function of the oncogene LYRIC/AEG-1 by ubiquitination at K486 and K491

Mol Oncol. 2014 May;8(3):633-41. doi: 10.1016/j.molonc.2014.01.009. Epub 2014 Jan 24.

Abstract

The pivotal role of LYRIC/AEG-1 in malignant transformation, tumourigenesis and chemo-resistance has previously been demonstrated in different cell types and sub-cellular compartments. The localisation of LYRIC/AEG-1 appears crucial to its function and is regulated by three lysine-rich nuclear localisation signal regions, one of which was previously demonstrated to be modified by ubiquitin. Here we show that mutation of LYRIC/AEG-1 at K486 and K491 results in a loss of ubiquitination. A K486/491R double mutant that is incapable of ubiquitination shows reduced binding to the NFκB subunit p65 or importin-β resulting in a distinctive peri-nuclear localisation of LYRIC/AEG-1. We also provide evidence to suggest that TOPORS, an E3 ligase that also regulates p53 modification may be responsible for LYRIC/AEG-1 ubiquitin modification. Overall we demonstrate that specific sites of LYRIC/AEG-1 ubiquitination are essential for regulating LYRIC/AEG-1 localisation and functionally interacting proteins.

Keywords: Localisation; Oncogene; Protein–protein interaction; Ubiquitin.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • COS Cells
  • Cell Adhesion Molecules / analysis
  • Cell Adhesion Molecules / genetics
  • Cell Adhesion Molecules / metabolism*
  • Chlorocebus aethiops
  • Humans
  • Membrane Proteins
  • Point Mutation
  • Protein Interaction Maps
  • RNA-Binding Proteins
  • Ubiquitin / metabolism
  • Ubiquitination*

Substances

  • Cell Adhesion Molecules
  • MTDH protein, human
  • Membrane Proteins
  • RNA-Binding Proteins
  • Ubiquitin