One nanogram of amplified cDNA was used for paired-end library preparation using the Nextera XT DNA library prep kit (Illumina, San Diego, CA) according to the manufacturers instructions. laser microdissection and differential RNA-seq approach, validated by in situ hybridization, to identify candidate molecular mechanisms underlying mouse OEC development CEBPE and differences with the neural crest-derived Schwann cells developing on other peripheral nerves. We identified 25 novel markers for developing Calcipotriol monohydrate OECs in the olfactory mucosa and/or the olfactory nerve layer surrounding the olfactory bulb, of Calcipotriol monohydrate which 15 were OEC-specific (that is, not expressed by Schwann cells). One pan-OEC-specific gene, (Jourdon et al., 2016), and are enriched (over outer ONL-OECs and mucosal OECs) for the secreted Wnt inhibitor gene (Rich et al., 2018). Conversely, outer ONL-OECs and mucosal OECs were reported to express the low-affinity neurotrophin receptor p75NTR (Au et al., 2002; Au et al., 2002; Franceschini & Barnett, 1996), while a subset of OECs at the outer edge of the ONL expresses the secreted semaphorin gene (Schwarting et al., 2000). In addition to these molecular differences in vivo, olfactory axons cocultured with mucosal OECs are less dispersed than those cocultured with rostral Calcipotriol monohydrate ONL-OECs containing a mixture of inner and outer ONL-OECs (Windus et al., 2010). Furthermore, mucosal OECs mostly adhere to other mucosal OECs in culture, while ONL-OECs are more heterogeneous in their response to other ONL-OECs, showing contact-adhesion, contact-repulsion, and cross-over, that is, exploration without either adhesion or repulsion (Windus et al., 2010). Physiological differences have also been identified between different OEC subpopulations. Outer but not inner ONL-OECs show an increase in intracellular calcium in response to a variety of agonists (Thyssen et al., 2013). Conversely, inner but not outer ONL-OECs propagate Ca2+ waves via gap junctions and display inward rectifier (Kir) potassium currents (Rela, Bordey, & Greer, 2010; Rela, Piantanida, Bordey, & Greer, 2015; Stavermann et al., 2015). Taken together, these molecular and phenotypic differences between different OEC subpopulations in vivo and in vitro provide indirect support for the hypothesis that mucosal OECs help fasciculate olfactory axons into heterotypic bundles, whereas outer ONL-OECs defasciculate them, and inner ONL-OECs help to sort Calcipotriol monohydrate and refasciculate homotypic axons (Ekberg et al., 2012; Ekberg & St John, 2014). Indeed, olfactory axon targeting is disrupted in mouse embryos lacking the earliest known marker for developing OECs and maintained throughout mucosal and ONL-OEC development (Barraud et al., 2010; Barraud et al., 2013; Forni et al., 2011), disrupts OEC differentiation and, in turn, olfactory axon targeting (Barraud et al., 2013; Pingault et al., 2013). Sox10 deletion (but not deletion; Rich et al., 2018) also significantly reduces the proportion of gonadotropin-releasing hormone (GnRH) neurons that enter the embryonic forebrain (Barraud et al., 2013; Pingault et al., 2013). GnRH neurons are surrounded by OECs as they migrate along olfactory, vomeronasal and terminal nerve axons to the forebrain (Geller et al., 2017; Geller, Kolasa, Tillet, Duittoz, & Vaudin, 2013; Taroc, Prasad, Lin, & Forni, 2017), where they are required in the adult hypothalamus for fertility (Cariboni, Maggi, & Parnavelas, 2007; Forni & Wray, 2015). What molecular variations between OEC subpopulations (mucosal OECs, outer ONL-OECs, inner ONL-OECs) might underlie the postulated variations in their connection with olfactory axons (Ekberg et al., 2012; Ekberg & St John, 2014), and also maybe their relationships with migrating GnRH neurons? How are such variations founded during OEC development? To what degree do the molecular mechanisms controlling OEC development, and the formation of unique OEC subpopulations, differ from those that underlie Schwann cell development? The transcriptional profiles of late-embryonic or adult mucosal OECs, ONL-OECs and/or Schwann cells have previously been compared using microarrays (Franssen, De Bree, Calcipotriol monohydrate Essing, Ramn-Cueto, & Verhaagen, 2008; Gurout et al., 2010; Pastrana et al., 2006; Roet, Bossers, Franssen, Ruitenberg, & Verhaagen, 2011; Ulrich et al., 2014;.