Analysis of alpha 3 GlyR single particle tracking in the cell membrane

Kristof Notelaers, Susana Rocha, Rik Paesen, Nick Smisdom, Ben De Clercq, Jochen C. Meier, Jean-Michel Rigo, Johan Hofkens, Marcel Ameloot*

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

Abstract

Single particle tracking (SPT) of transmembrane receptors in the plasma membrane often reveals heterogeneous diffusion. A thorough interpretation of the displacements requires an extensive analysis suited for discrimination of different motion types present in the data. Here the diffusion pattern of the homomeric alpha3-containing glycine receptor (GlyR) is analyzed in the membrane of HEK 293 cells. More specifically, the influence of the alpha3 RNA splice variants alpha3K and alpha3L on lateral membrane diffusion of the receptor is revealed in detail. Using a combination of ensemble and local SPT analysis, free and anomalous diffusion parameters are determined. The GlyR alpha3 free diffusion coefficient is found to be 0.13 +/- 0.01 microm2/s and both receptor variants display confined motion. The confinement probability level and residence time are significantly elevated for the alpha3L variant compared to the alpha3K variant. Furthermore, for the alpha3L GlyR, the presence of directed motion was also established, with a velocity matching that of saltatory vesicular transport. These findings reveal that alpha3 GlyRs are prone to different types of anomalous diffusion and reinforce the role of RNA splicing in determining lateral membrane trafficking.
Original languageEnglish
Pages (from-to)544-553
JournalBiochimica et Biophysica Acta-Molecular Cell Research
Volume1843
Issue number3
DOIs
Publication statusPublished - Mar 2014

Keywords

  • Glycine receptor
  • Alpha3 subunit
  • RNA splicing
  • Single particle tracking
  • Confined motion
  • Directed motion

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