Fig. 3. Coordinated regulation of transcription factor expression in sensory ganglia by Brn3a. (A) In situ hybridization analysis of E13.5 embryos for expression of the transcription factors GATA3, Irx1, Irx2, MyoR, Ap2ß and Math3, all of which exhibited increased expression in the microarray analysis in Brn3a knockout ganglia. (B) Expression of mRNA for the decreased transcription factors HoxD1 and Runx1. In addition to the cranial sensory ganglia, each of these factors also exhibited previously known patterns of expression in the CNS, and in the case of MyoR, in developing cranial musculature. The plane of section used in all views is shown in Fig. 2A. 5g, trigeminal ganglion; 8g, vestibulocochlear ganglion; 9g, IX/X ganglion complex; di, diencephalon; hb, hindbrain; m, differentiating occipital musculature; ot, otic region; tel, telencephalon; sc, spinal cord.