At the final neurogenic cell division, a shift in BAF composition occurs at three subunit positions: BAF53a is switched for BAF53b, SS18 for CREST, and BAF45a/d for BAF45b/c (Wu et al., 2007; Olave et al., 2002) (Figure 1). Immunostaining in the developing embryonic spinal cord reveals a clear boundary between the Ki67+ proliferative zone which expresses npBAF subunits, and the β-Tubulin-III+ postmitotic zone which expresses the homologous neuronal BAF (nBAF) subunits (Lessard et al., 2007; Staahl et al., 2013). The nBAF-specific subunits are not found in any other cell type examined to date and are thus exclusively involved in remodeling the postmitotic neuronal chromatin. Deletion of the nBAF-specific subunits affects differentiated neurons, in contrast to npBAF subunits whose disruption affects the progenitor population.
