Figure 6.

Simultaneous visualization of SCb proteins reveal that they are cotransported anterogradely. Cultured hippocampal neurons were double transfected with mRFP::α-SYN and either GFP::SYS-I or GFP::GAPDH (all SCb proteins) and visualized by simultaneous dual-color video microscopy. A–F show selected frames and kymographs from dual-cam imaging. Each set of frames shows α-synuclein (red) and synapsin-I or GAPDH (green), with the corresponding overlay image (yellow). Each three-frame kymograph panel shows the mRFP::α-SYN kymograph (left), GFP::SYS-I or GFP::GAPDH kymograph (middle), and a pseudocolor overlay of anterograde tracings from the respective kymographs (right). The yellow lines in overlaid kymographs represent cotransport. A, B, Cotransport of an object (arrowhead) positive for mRFP::α-SYN and GFP::SYS-I; the asterisk marks a stationary object. Arrowheads and asterisks in B represent movement of correspondingly marked particles in the frames above. C, Additional kymograph showing cotransport and pausing of an anterograde mRFP::α-SYN/GFP::SYS-I object. D, E, Cotransport of an object (arrowhead) positive for mRFP::α-SYN and GFP::GAPDH with corresponding kymographs. F, Additional examples of mRFP::α-SYN/GFP::GAPDH cotransport. (For corresponding videos, see supplemental videos 6 and 7, available at www.jneurosci.org as supplemental material.) Scale bars for the kymographs are at the bottom left of the kymograph(s). Scale bar, 5 μm.