Cortical Interneurons Refuse to Follow the PAK

The tangential migration of GABAergic interneurons to the cortex requires the activity of several transcription factors, but the mechanisms involved have remained elusive. In this issue of Neuron, Rubenstein and colleagues demonstrate that the homeobox proteins Dlx1 and Dlx2 promote interneuron migration in part by preventing the premature expression of PAK3, a serine/threonine kinase that is later involved in neurite outgrowth and other aspects of interneuron maturation.