Genetically Distinct SOM Interneuron Subsets

To label genetically distinct subsets of SOM interneurons, we crossed Sst-Flp mice (catalog #028579, The Jackson Laboratory; He et al., 2016 (link)) with one of the following four Cre recombinase-expressing mouse lines: Calb2-Cre (strain #010774, The Jackson Laboratory; Taniguchi et al., 2011 (link)), Calb1-Cre (strain #028532, The Jackson Laboratory; Daigle et al., 2018 (link)), Chrna2-Cre (Leão et al., 2012 (link)), and Pdyn-Cre (strain #027958, The Jackson Laboratory; Krashes et al., 2014 (link)). Dual-recombinase progeny were then crossed with the RC::FLTG reporter line (strain #026932, The Jackson Laboratory; Plummer et al., 2015 (link)) to create triple-transgenic mice expressing GFP in Cre⁺/Flp⁺ cells and tdTomato in Cre^–/Flp⁺ cells. We also used X94 and X98 mice (strains #006340 and #006334, The Jackson Laboratory; Ma et al., 2006 (link)) to label previously characterized subsets of L4-projecting and L1-projecting SOM cells, respectively, crossing them with Cre driver lines and the Ai9 tdTomato reporter (strain #007909, The Jackson Laboratory; Madisen et al., 2010 (link)).