Quantitative analysis of APP axonal transport in neurons: role of JIP1 in enhanced APP anterograde transport.
Bottom Line: In JIP1-deficient neurons, we find that both the fast velocity (∼2.7 μm/s) and high frequency (66%) of anterograde transport of APP cargo are impaired to a reduced velocity (∼1.83 μm/s) and a lower frequency (45%).Furthermore, efficient APP axonal transport is not influenced by phosphorylation of APP at Thr-668, a site known to be phosphorylated by JNK.Our quantitative analysis indicates that enhanced fast-velocity and efficient high-frequency APP anterograde transport observed in neurons are mediated by novel roles of JIP1b.
Affiliation: Laboratory of Neuroscience, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan.Show MeSH
Mentions: The role of JIP1b in efficient anterograde transport of APP cargo was examined by detailed analysis of the interaction of JIP1b and KLC1. First, we expressed four region-deleted KLC1 proteins with N-terminal hemagglutinin (HA) or C-terminal EGFP tags in COS7 cells and examined their binding to N-terminal FLAG-JIP1b or FLAG-JIP1bΔC11, the latter lacking the 11 known KLC-binding C-terminal amino acids (schematic protein structures are shown in Figure 3A).
Affiliation: Laboratory of Neuroscience, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan.