Fig. 1

Gpr62 expression is highly enriched in mature oligodendrocytes, where the protein is localized along the myelin sheath. A Expression of Gpr62 in astrocytes, neurons, OPCs, newly formed oligodendrocytes, myelinating oligodendrocytes, microglia and brain endothelial cells acutely purified from the postnatal mouse brain. Expression data from [35] nfOL: Newly-formed oligodendrocyte. mOL: Myelinating oligodendrocyte. (B) Single cell RNA-Seq indicates that Gpr62 expression is restricted to myelin forming and mature oligodendrocytes. Expression data and t-SNE plot of oligodendroglia from [36]. (C) Design of AAV expression constructs to express eGFP or Gpr62-Flag behind 1.9 kb of the Mbp promoter. AAVs were injected into the corpus callosum and striatum of P6 mice. (D) AAV-mediated expression of eGFP or Gpr62-Flag in the infected corpus callosum and overlying cortex. As previously published [33, 37], the 1.9 kb Mbp promoter strongly drove eGFP expression in mature (CC1+) oligodendrocytes. Gpr62-Flag expression was faint or absent in oligodendrocyte cell bodies, but readily detectable along myelin internodes. Scale bars: 50 μm. (E) Both eGFP and Gpr62-Flag expressing myelin internodes were flanked by Caspr+ paranodes, confirming oligodendroglial rather than axonal expression of the AAV constructs. Scale bars: 5 μm