Cotransport of NF186 and NrCAM depends on their ABD. (A) Schematic diagram of chimeric constructs and their domain organizations. (B and D) Kymographs of neurons expressing NF186-mKate2 (red) and either ICAM (green; top panels) or NF/ICAM (green; bottom panels) in the anterograde (B) or retrograde (D) direction. (C and E) Quantification of vesicles that cotransport NF186-mKate2 with ICAM or NF/ICAM versus total numbers of NF186-positive vesicles in the anterograde (C) and retrograde (E) directions. Numbers of axons analyzed in the anterograde direction were ICAM-EGFP, n = 15 and ICAM/NF186, n = 17; in the retrograde direction, ICAM-EGFP, n = 20, and ICAM/NF186, n = 30. Statistical significance was determined by two-tailed Welch’s t test for unpaired data, with asterisks indicating a P value of ****, P < 0.001. Error bars indicate mean ± SEM. (F and H) Upper duplicate kymographs show trafficking of vesicles in neurons infected with NF186-mKate2 (red) and NF186ΔABD-EGFP (green) in the anterograde (F) and retrograde (H) directions; in each case, an example of a transport vesicle is circled below. The bottom duplicate kymographs show trafficking of vesicles in neurons infected with NrCAM-mKate2 (red) and NF186ΔABD-EGFP (green) with an example shown circled below. Scale bars, 1 µm. (G and I) Bar graphs show the percentages of cotransported vesicles versus total NF186-mKate2 or NrCAM-mKate2 vesicles in the anterograde (G) and retrograde (I) directions. Numbers of axons analyzed in the anterograde direction: NF186ΔABD-EGFP with NF186-mKate2, n = 19, and with NrCAM-mKate2, n = 13; in the retrograde direction: NF186ΔABD-EGFP with NF186-mKate2, n = 20, and with NrCAM-mKate2, n = 14. Statistical significance was determined by two-tailed Welch’s t test for unpaired data, with asterisks indicating P values of ****, P < 0.001 and **, P < 0.01. Error bars indicate mean ± SEM.