FIG. 5.

Sizn1 plays a role in BMP-dependent, cholinergic-neuron-specific gene expression. (A) Immunostaining of Sizn1 and AChE in a coronal section of an E13.5 mouse brain, indicating that Sizn1 is expressed in cholinergic neurons. LGE, lateral ganglionic eminence; MGE, medial ganglionic eminence. Scale bar = 100 μm. (B) Knockdown of Sizn1 in SN56 septum cells after transfection of three kinds of shRNA. Lane 1 contains the control (nontargeting negative-control shRNA), and lanes 2 to 4 contain shRNA against Sizn1 (targets I to III). Target II was used for the introduction of shRNA to primary septum cells for qRT-PCR. (C) qRT-PCR analysis of relative mRNA levels for Sizn1, ChAT, and VaChT after Sizn1 knockdown with shRNA (target II) in the primary septal culture in the presence of BMP-2. The Sizn1 mRNA level is significantly reduced (by ∼60%) by treatment with Sizn1 shRNA (n = 3). ChAT and VaChT expression is also repressed by Sizn1 shRNA in the presence of BMP-2 (means ± SDs). *, P = 0.02; **, P = 0.007; ***, P = 0.016. bFGF (20 ng/ml) was added to each sample to maintain high precursor cell numbers.