Brains were dissected and sectioned at 500 μm on ice in a stainless steel brain matrix (EMS 69090-C). PFC or CeA was microdissected in ice-cold PBS with 1x protease inhibitors (Roche) under a stereomicroscope. The tissue was resuspended in 500µl homogenization buffer containing 300mM sucrose, 60mM KCl, 15mM NaCl, 15mM Tris-HCl, 5mM MgCl2, 0.1mM EGTA, 1 mM DTT, 0.1mM PMSF and 1x protease inhibitors, EDTA-free (Roche), and disrupted using a cordless pestle motor homogenize tissue with 4 bursts of 5 seconds. Nuclei were prepared by a seven minute detergent lysis with the addition of IGEPAL CA-630 (Sigma) to a final concentration of 0.2%, followed by pelleting at 1500rcf and gentle resuspension in PBS containing 2% FBS for FACS sorting. Nuclei were filtered through 40 μm cell strainers and NucBlue was added to SOMErbb4-KO nuclei, while SOMH2B-GFP were gated on GFP. Nuclei were sorted into technical replicates of 50,000 nuclei and immediately proceeded to the ATAC-seq transposition reaction. For each library, 50,000 sorted nuclei were resuspended in Transposition Reaction Mix then incubated at 37° C. Using Qiagen MinElute Kit we purified 50uL reaction volume. Transposed DNA were stored at -20C. We used the primers in Buenrostro et al (2013) for library construction. ATAC-seq library quality was assessed on an agarose gel with 1X SYBR Gold to view banding. Libraries were quantified by both Bioanalyzer High Sensitivity Chips and the KAPA Illumina Library Quantification kit.