Biomedical Engineering Reference
In-Depth Information
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Figure 6.2 A model for growth cone polarity and growth cone turning. Blue lines rep-
resent microtubules, which have plus ends pointing toward the distal end of the growth
cone. The thickness of microtubules represents their stability. Green indicates the local-
ization of some signaling molecules, which may be asymmetrically localized, such as
Vangl2 (
Shafer et al., 2011
).
Perhaps a unique feature about growth cone polarity is that polarity is much
more dynamic than stationary cells and the direction of polarity can change,
for example, during turning. Recent studies show that both apical-basal and
planar polarity signaling components in epithelial polarity are involved in
Wnt-mediated turning (
Fenstermaker et al., 2010; Shafer et al., 2011;
Wolf et al., 2008
). This suggests that the growth cone may engage these
potent cell polarity regulators to change its polarity in response to
guidance cues to achieve turning.
