Target genes with decreased expression in the DRG of Brn3a null mice. (a) In situ hybridization confirms decreased expression of multiple Brn3a downstream targets. (b) Immunofluorescence for the galanin neuropeptide shows marked reduction in the dorsal horn and dorsal root entry zone of Brn3a null DRG. All views show lower cervical (brachial) level cross sections of E13.5 embryos. Scale: 200 μm (a), 100 μm (b).