Expanding the Interactome of TES by Exploiting TES Modules with Different Subcellular Localizations

J Proteome Res. 2017 May 5;16(5):2054-2071. doi: 10.1021/acs.jproteome.7b00034. Epub 2017 Apr 20.


The multimodular nature of many eukaryotic proteins underlies their temporal or spatial engagement in a range of protein cocomplexes. Using the multimodule protein testin (TES), we here report a proteomics approach to increase insight in cocomplex diversity. The LIM-domain containing and tumor suppressor protein TES is present at different actin cytoskeleton adhesion structures in cells and influences cell migration, adhesion and spreading. TES module accessibility has been proposed to vary due to conformational switching and variants of TES lacking specific domains target to different subcellular locations. By applying iMixPro AP-MS ("intelligent Mixing of Proteomes"-affinity purification-mass spectrometry) to a set of tagged-TES modular variants, we identified proteins residing in module-specific cocomplexes. The obtained distinct module-specific interactomes combine to a global TES interactome that becomes more extensive and richer in information. Applying pathway analysis to the module interactomes revealed expected actin-related canonical pathways and also less expected pathways. We validated two new TES cocomplex partners: TGFB1I1 and a short form of the glucocorticoid receptor. TES and TGFB1I1 are shown to oppositely affect cell spreading providing biological validity for their copresence in complexes since they act in similar processes.

Keywords: VASP; Zyxin; actin; affinity purification−mass spectrometry; cell spreading; focal adhesion; glucocorticoid receptor; pathway analysis; protein−protein interaction; transforming growth factor beta 1 induced 1.

MeSH terms

  • Actins / metabolism
  • Cytoskeletal Proteins / metabolism*
  • Focal Adhesions / metabolism
  • Humans
  • Intracellular Signaling Peptides and Proteins / metabolism
  • Intracellular Space / metabolism
  • LIM Domain Proteins / metabolism*
  • Protein Multimerization
  • Proteomics / methods
  • RNA-Binding Proteins


  • Actins
  • Cytoskeletal Proteins
  • Intracellular Signaling Peptides and Proteins
  • LIM Domain Proteins
  • RNA-Binding Proteins
  • TES protein, human
  • TGFB1I1 protein, human