TY - JOUR
T1 - PIP3 is involved in neuronal polarization and axon formation
AU - Ménager, Céline
AU - Arimura, Nariko
AU - Fukata, Yuko
AU - Kaibuchi, Kozo
N1 - Copyright:
Copyright 2018 Elsevier B.V., All rights reserved.
PY - 2004/4
Y1 - 2004/4
N2 - Recent experiments in various cell types such as mammalian neutrophils and Dictyostelium discoideum amoebae point to a key role for the lipid product of PI 3-kinase, PIP3, in determining internal polarity. In neurons, as a consequence of the elongation of one neurite, the axon is specified and the cell acquires its polarity. To test the hypothesis that PI 3-kinase and PIP 3 may play a role in neuronal polarity, and especially in axon specification, we observed localization of PIP3 visualized by Akt-PHGFP in developing hippocampal neurons. We found that PIP3 accumulates in the tip of the growing processes. This accumulation is inhibited by addition of PI 3-kinase inhibitors. Those inhibitors, consistently with a role of PIP3 in process formation and elongation, delay the transition from stage 1 neurons to stage 3 neurons, and both axon formation and elongation. Moreover, when the immature neurite contacts a bead coated with laminin, a substrate known to induce axon specification, PIP3 accumulates in its growth cone followed by a rapid elongation of the neurite. In such conditions, the addition of PI 3-kinase inhibitors inhibits both PIP3 accumulation and future axon elongation. These results suggest that PIP3 is involved in axon specification, possibly by stimulating neurite outgrowth. In addition, when a second neurite contacted the beads, this neurite rapidly elongates whereas the elongation of the first laminin-contacting neurite stops, consistently with the hypothesis of a negative feedback mechanism from the growing future axon to the other neurites.
AB - Recent experiments in various cell types such as mammalian neutrophils and Dictyostelium discoideum amoebae point to a key role for the lipid product of PI 3-kinase, PIP3, in determining internal polarity. In neurons, as a consequence of the elongation of one neurite, the axon is specified and the cell acquires its polarity. To test the hypothesis that PI 3-kinase and PIP 3 may play a role in neuronal polarity, and especially in axon specification, we observed localization of PIP3 visualized by Akt-PHGFP in developing hippocampal neurons. We found that PIP3 accumulates in the tip of the growing processes. This accumulation is inhibited by addition of PI 3-kinase inhibitors. Those inhibitors, consistently with a role of PIP3 in process formation and elongation, delay the transition from stage 1 neurons to stage 3 neurons, and both axon formation and elongation. Moreover, when the immature neurite contacts a bead coated with laminin, a substrate known to induce axon specification, PIP3 accumulates in its growth cone followed by a rapid elongation of the neurite. In such conditions, the addition of PI 3-kinase inhibitors inhibits both PIP3 accumulation and future axon elongation. These results suggest that PIP3 is involved in axon specification, possibly by stimulating neurite outgrowth. In addition, when a second neurite contacted the beads, this neurite rapidly elongates whereas the elongation of the first laminin-contacting neurite stops, consistently with the hypothesis of a negative feedback mechanism from the growing future axon to the other neurites.
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U2 - 10.1046/j.1471-4159.2004.02302.x
DO - 10.1046/j.1471-4159.2004.02302.x
M3 - Article
C2 - 15030394
AN - SCOPUS:1842614409
VL - 89
SP - 109
EP - 118
JO - Journal of Neurochemistry
JF - Journal of Neurochemistry
SN - 0022-3042
IS - 1
ER -