Unidirectional Transport of Internalized BACE1 in Dendrites - Buggia-Prevot et al. Cell Reports 2013

After internalization in endosomes, the Alzheimer's disease-related protein BACE1 undergoes unidirectional transport in dendrites toward the cell body although the total pool of BACE1 is able to move in both direction. BACE1 is the only protein described  so far that is transported undirectionally despite the microtubules mixed polarity in dendrite .
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A Function for EHD Family Proteins in Unidirectional Retrograde Dendritic Transport of BACE1 and Alzheimer's Disease Aβ Production - Movie S1
Cell Reports - 26 December 2013 (Vol. 5, Issue 6, pp. 1552-1563)
http://www.cell.com/cell-reports/abstract/S2211-1247%2813%2900736-5