Cell migration: GSK3β steers the cytoskeleton's tip

Abstract

Directed cell migration polarizes the cytoskeleton, allowing the cell to move toward migratory cues. In this issue, Wu et al. (2011) demonstrate that the glycogen synthase kinase 3β (GSK3β) controls microtubule architecture and polarized movement of skin stem cells during wound healing in mammals by regulating the microtubule crosslinking protein ACF7.

Figure 1. GSK3β Is a Central Regulator of the Cytoskeleton during Cell Migration

In nonmigrating cells, GSK3β is normally active and phosphorylates proteins that associate with the plus (+) ends of microtubule filaments, called “+tip proteins.” Phosphorylation uncouples +tip proteins from microtubules (Wu et al., 2011), inhibiting growth of the filaments. Migratory cues, such as Heregulin, inactivate GSK3β by phosphorylation (Zaoui et al., 2010), allowing the local extension of microtubules by +tip proteins. This helps to polarize the cytoskeleton and direct cellular movement toward the migratory cues