Bcl11a (Ctip1) controls migration of cortical projection neurons through regulation of Sema3c

During neocortical development, neurons undergo polarization, oriented migration, and layer type-specific differentiation. The transcriptional programs underlying these processes are not completely understood. Here we show that the transcription factor Bcl11a regulates polarity and migration of upper layer neurons. Bcl11a-deficient late-born neurons fail to correctly switch from multipolar to bipolar morphology resulting in impaired radial migration. We show that the expression of Sema3c is increased in migrating Bcl11a-deficient neurons and that Bcl11a is a direct negative regulator of Sema3c transcription. In vivo gain-of-function and rescue experiments demonstrate that Sema3c is a major downstream effector of Bcl11a required for the cell polarity switch and for the migration of upper layer neurons. Our data uncover a novel Bcl11a/Sema3c-dependent regulatory pathway used by migrating cortical neurons.

6

Wiegreffe C, Simon R, Peschkes K, Kling C, Strehle M, Cheng J, Srivatsa S, Liu P, Jenkins NA, Copeland NG, Tarabykin V, Britsch S