The values of various diffusive behaviors of sPH-AP-QDs analyzed in this study.

<p>Actin, actin cytoskeleton disrupted; Microtubule, microtubule disrupted; Gly-SP, Glycine-induced synaptic potentiation; NMDA-SD, NMDA-induced synaptic depression; D_synapse, diffusion coefficient at synapses; D_ex-synapse, diffusion coefficient at extrasynapses; All values are mean ± s.e. *p<0.01, paired <i>t</i>-test.</p

Single QD tracking of synaptic vesicles using sPH-AP-QDs.

<p>(<b>A</b>) Hippocampal neurons were co-transfected with sPH-AP and Bir-ER at DIV 12, and labeled with 1 nM streptavidin-conjugated-QD at DIV17. Blue color: the functional presynaptic terminals were identified by sPH fluorescence change (ΔF). Scale bar, 20 µm. (<b>B</b>) Example of sPH-AP-QDs (red) trafficking along the axon (green). Arrows: sPH-AP-QDs trafficking between synaptic and extrasynaptic compartments, arrowheads: sPH-AP-QDs at presynaptic terminals. asterisks: functional presynaptic terminals (blue). Scale Bar, 2.5 µm. (<b>C</b>) Instantaneous displacement change of the moving sPH-AP-QD marked by the arrow in (<b>B</b>) from its initial location (displacement = 0) along the axon during recording sequence. The <i>x</i> and <i>y</i> coordinates of QD trajectory at each time point in time-lapse images were obtained using MetaMorph track object function and the displacement from the origin to the QD trajectory at each time point was calculated and plotted. The graph parallel to <i>y</i> axis means no movement. The upper lines denote the frames in which the sPH-AP-QD is at extrasynaptic areas (gray) and synapses (red and shaded areas). (<b>D</b>) MSD versus time, calculated for a continuous sequence of images, which show the synaptic motion (red) and extrasynaptic motion (blue). Inset represents average diffusion coefficient of sPH-AP-QDs at synapses (red) and at extrasynapses (blue).</p