Expression of Cited1, a p300-binding transcriptional co-activator that promotes signaling in the TGF-beta pathway (Gerstner and Landry, 2007) was increased in the SVZ of the ventral MGE and POA in both the Nkx2.1-Cre and DlxI12b-Cre mutants (Figures S5S-S5U’ and S5QQ-S5SS’). This is of interest given that ZFHX1B acts as a SMAD-binding transcriptional co-repressor (Vandewalle et al., 2008). Thus, Cited1 and Zfhx1b may function antagonistically in MGE development. Gpc4 expression in the SVZ of the MGE was increased in both mutants (Figure S5V-S5X’ and S5TT-S5WW’). Glypicans (GPC) are extracellular matrix proteins that promote FGF-signaling (Jen et al., 2009).
