Cellular FRET-Biosensors to Detect Membrane Targeting Inhibitors of N-Myristoylated Proteins

PLoS One. 2013 Jun 18;8(6):e66425. doi: 10.1371/journal.pone.0066425. Print 2013.

Abstract

Hundreds of eukaryotic signaling proteins require myristoylation to functionally associate with intracellular membranes. N-myristoyl transferases (NMT) responsible for this modification are established drug targets in cancer and infectious diseases. Here we describe NANOMS (NANOclustering and Myristoylation Sensors), biosensors that exploit the FRET resulting from plasma membrane nanoclustering of myristoylated membrane targeting sequences of Gαi2, Yes- or Src-kinases fused to fluorescent proteins. When expressed in mammalian cells, NANOMS report on loss of membrane anchorage due to chemical or genetic inhibition of myristoylation e.g. by blocking NMT and methionine-aminopeptidase (Met-AP). We used Yes-NANOMS to assess inhibitors of NMT and a cherry-picked compound library of putative Met-AP inhibitors. Thus we successfully confirmed the activity of DDD85646 and fumagillin in our cellular assay. The developed assay is unique in its ability to identify modulators of signaling protein nanoclustering, and is amenable to high throughput screening for chemical or genetic inhibitors of functional membrane anchorage of myristoylated proteins in mammalian cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Biosensing Techniques*
  • Cell Line
  • Cell Membrane / metabolism*
  • Cluster Analysis
  • Cricetinae
  • Fluorescence Resonance Energy Transfer
  • Humans
  • Membrane Proteins / metabolism*
  • Myristic Acid / metabolism*

Substances

  • Membrane Proteins
  • Myristic Acid

Grants and funding

This work was supported National Health and Medical Research Council grant 569652 (Australia), ARC grant DP1094080 (Australia) (www.nhmrc.gov.au/www.arc.gov.au/). Additional support was provided by the Academy of Finland fellowship grant (252381), the Sigrid Juselius Foundation, the Cancer Society of Finland and the Marie-Curie Reintegration Grant to DA (268271). AKN is grateful for support by the graduate school, National Doctoral Programme in Informational and Structural Biology (ISB) (http://web.abo.fi/isb/). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.