Quantum dot labelling of single receptors using the α-bungarotoxin site

We have extended use of the α-bungarotoxin site to study the lateral mobility of multiple neurotransmitter receptors

The approach

Recombinant receptors are labelled with quantum dots (QDs) after expression in cultured hippocampal neurons using low 200–400 nM concentrations of α-BgTx-biotin (BgTx-B) and 50 pM QD655 streptavidin.

Neurons are transfected with single receptor subunit constructs along with eGFP at 7 days in vitro (DIV) and imaged at 12–14 DIV.

Under these conditions, specific labelling is QDs observed when BBS-tagged receptor subunits were expressed.

Labelling with QDs is negligible when untagged GABA_AR subunits or just eGFP were expressed. Moreover, no labelling is observed when BBS-tagged receptors were incubated in unlabelled α-BgTx along with QD655 further validating the specificity of our labelling.

Real-time tracking of single receptors around synapses

This strategy allows real-time tracking of single receptors and the movement of receptors around synaptic and extrasynapic domains can be measured

For more details please visit the publications:

S Hannan, K Gerrow, A Triller & TG Smart. (2016). Phospho-dependent enrichment of mobile GABA_BRs at presynaptic terminals after NMDAR activation. Cell Reports 16, 1962-19739

S Hannan*, M Minere, J Harris, P Izquierdo, P Thomas, B Tench & TG Smart* (2020). GABA_AR isoform and subunit structural motifs determine synaptic and extrasynaptic receptor localisation. Neuropharmacology 169, 107540