Sez6l (clone ID 30362651), Syt1 (clone ID 5363062) cDNAs were obtained GE Dharmacon. Gad1 cDNA (nucleotides 1099–2081) was generated using Superscript II Reverse Transcriptase First Strand cDNA Synthesis kit (# 18064014, Invitrogen, La Jolla, CA) according to the manufacturer manual, amplified by PCR using following primers: F: TGTGCCCAAACTGGTCCT; R: TGGCCGATGATTCTGGTT (Integrated DNA Technologies), gel purified, and then cloned into a pGEM-T Easy Vector using pGEM-T Easy Vector kit, (cat # A1360, Promega, Madison, WI) according to the kit manual. Riboprobes against Gad1, Syt1 and Sez6l mRNAs were generated as described previously (Monavarfeshani et al. 2017a (link)). ISH was performed on 16 μm PFA-perfused coronally cryosectioned brain tissue (n = 3 mice) prepared as described above. Tissues were prepared and hybridized at 60°C as previously described (Monavarfeshani et al. 2018 (link), Su et al. 2010 (link)). Bound riboprobes were detected by either horseradish peroxidase (POD)-conjugated anti-DIG or anti-fluorescent antibodies (Roche #: 11426346910 and 11207733910), followed by Tyramide Signal Amplification systems (PerkinElmer #: NEL75300 1KT). Slides were visualized on a Zeiss LSM 700 confocal microscope. Images were acquired with identical parameters were used to compare sections from different genotypes.