During cortical development, newborn projection neurons undergo radial migration to reach the cortical plate (CP). Cell branching of migrating neurons has been recognized as a critical process for both exploring migration cues and finding the correct directions during migration. To this end, proper cellular branching is essential for correct migration and normal brain function (Evsyukova et al., 2013). B-cell activating factor (BAFF) is essential for B-cell homeostasis during cell maturation, survival, and differentiation, which occurs primarily through the B-cell receptor, BAFF receptor (BR3, also known as TNFRSF13C) (Warnatz et al., 2009). In addition to their essential roles in the immune system, BAFF and B-cell receptors have been found to be upregulated in human neurological diseases (Saltzman et al., 2013). We reported previously that BAFF inhibits neurite outgrowth through interacting with the Nogo-66 receptor (Zhang et al., 2009). However, whether or not they are involved in brain development as intrinsic factors remains unclear.
