Figure 1. EB1/3 proteins are differentially regulated by classical MAPs in developing or mature neurons. (A) In differentiating neurons, MAP1B, which is expressed at high levels, sequesters EB1/3 in the cytosol (see detail in growth cone). This contributes to maintain MTs in a highly dynamic state during axon outgrowth. (B) In dendrites of mature neurons, neuronal activation (e.g., by NMDA) induces MAP2 dephosphorylation and binding to MTs, leading to MT bundling. Dephosphorylated MAP2 recruits EB1/3 to MT bundles, thus decreasing MT dynamics and increasing MT stability in dendrites. EB1/3 proteins are also found along the MT lattice at the AIS, interacting with ankyrin G and maybe with other MAPs.