Format

Send to

Choose Destination
J Neurochem. 2015 Jun;133(5):653-67. doi: 10.1111/jnc.13091. Epub 2015 Apr 8.

Tau regulates the localization and function of End-binding proteins 1 and 3 in developing neuronal cells.

Author information

1
Centro de Biología Molecular "Severo Ochoa" (CSIC-UAM), Madrid, Spain; Centre for Biomedical Research of the Canary Islands (CIBICAN), Institute for Biomedical Technologies (ITB), University of La Laguna (ULL), Tenerife, Spain; Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain.

Abstract

The axonal microtubule-associated protein tau is a well-known regulator of microtubule stability in neurons. However, the putative interplay between tau and End-binding proteins 1 and 3 (EB1/3), the core microtubule plus-end tracking proteins, has not been elucidated yet. Here, we show that a cross-talk between tau and EB1/3 exists in developing neuronal cells. Tau and EBs partially colocalize at extending neurites of N1E-115 neuroblastoma cells and axons of primary hippocampal neurons, as shown by confocal immunofluorescence analyses. Tau down-regulation leads to a reduction of EB1/3 comet length, as observed in shRNA-stably depleted neuroblastoma cells and TAU-/- neurons. EB1/3 localization depends on the expression levels and localization of tau protein. Over-expression of tau at high levels induces EBs relocalization to microtubule bundles at extending neurites of N1E-115 cells. In differentiating primary neurons, tau is required for the proper accumulation of EBs at stretches of microtubule bundles at the medial and distal regions of the axon. Tau interacts with EB proteins, as shown by immunoprecipitation in different non-neuronal and neuronal cells and in whole brain lysates. A tau/EB1 direct interaction was corroborated by in vitro pull-down assays. Fluorescence recovery after photobleaching assays performed in neuroblastoma cells confirmed that tau modulates EB3 cellular mobility. In summary, we provide evidence of a new function of tau as a direct regulator of EB proteins in developing neuronal cells. This cross-talk between a classical microtubule-associated protein and a core microtubule plus-end tracking protein may contribute to the fine-tuned regulation of microtubule dynamics and stability during neuronal differentiation. We describe here a novel function for tau as a direct regulator of End binding (EB) proteins in differentiating neuronal cells. EB1/3 cellular mobility and localization in extending neurites and axons is modulated by tau levels and localization. We provide new evidence of the interplay between classical microtubule-associated proteins (MAPs) and "core" microtubule plus-end tracking proteins (+TIPs) during neuronal development.

KEYWORDS:

+TIPs; EBs; MAPs; microtubule dynamics; neuronal development; tau

PMID:
25761518
DOI:
10.1111/jnc.13091
[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for Wiley
Loading ...
Support Center