Single-molecule FRET analysis of the dynamics of AMPA receptor

[摘要] Single-molecule fluorescence resonance energy transfer (smFRET) spectroscopy has advanced to become a powerful tool in characterizing biomolecules to the molecular level. In this thesis, the smFRET technique was utilized for the first time to analyze the dynamics of the conformational changes of the ligand-binding domain (S1S2) of GluR2, a subunit of the ionotropic glutamate/AMPA receptor. The GluR2-SIS2 molecule was determined to have a more open cleft when the natural ligand glutamate is not present as compared to when glutamate is bound to the molecule. The apo and Glutamate-bound GluR2-S1S2 molecules in solution medium were observed to have more open cleft than when they are in crystallized forms. The smFRET technique has an advantage over x-ray crystallography because it can quantitatively analyze the conformations of the molecules and the interconversions between those states. The dynamics of the GluR2-S1S2 molecule elucidates the mechanism of activation of glutamate receptors.

[发布机构] Rice University

[效力级别] Neurosciences