Table 2.

Characteristics of the different categories of mobility of TrkB-EGFP and VAMP-DsRed colocalized puncta

	Anterograde	Retrograde	Bidirectional	Stationary	Total	Total mobile
TrkB/VAMP puncta	23 [12.4%]	45 [24.3%]	117 [63.2%]	65 (26.0%)	250 (89.3%)	185 [92.0%]
VAMP alone puncta	1 [16.7%]	1 [16.7%]	4 [66.7%]	2 (25.0%)	8 (2.9%)	6 [3.0%]
TrkB alone puncta	1 [10.0%]	3 [30.0%]	6 [60.0%]	12 (54.5%)	22 (7.9%)	10 [5.0%]
Total puncta	25 (8.9%) [12.4%]	49 (17.5%) [24.4%]	127 (45.4%) [63.2%]	79 (28.2%)	280	201 (71.8%)

Three to four DIV cortical neurons were cotransfected with TrkB-EGFP and VAMP-DsRed. Twenty-four to 36 h after transfection, transfected neurons were imaged for mobility of colocalized puncta in axons; images were captured every 10 s for 10 min. All puncta containing either fluorophore that were 2× the local background intensity (defined using line-scan analysis) and could be tracked for at least four frames were included in the analysis. The numbers in the table correspond to the number of puncta with each behavior pooled from a total of 12 axons from 12 neurons. Numbers in parentheses correspond to the percent of total puncta within each category and numbers in brackets the percent of mobile puncta. Most TrkB-EGFP puncta were colocalized and moved together with VAMP-DsRed. The mobility of the small proportion of VAMP-DsRed alone and TrkB-EGFP alone puncta was generally similar to that of the colocalized puncta.