MEP glia share molecular features with oligodendrocytes while maintaining a distinct hybrid signature.

Motor Exit Point (MEP) glia are spinal cord-derived glial cells that myelinate peripheral motor axons, bridging the central and peripheral nervous systems. They have a hybrid profile, sharing features with oligodendrocytes and Schwann cells. Yet, significant gaps remain in our understanding of complex MEP glial lineage and identity. MEP glia express neural tube and canonical oligodendrocyte lineage markers olig2 and nkx2.2a , as well as the neural crest marker foxd3 . Here, we show that the oligodendrocyte markers olig1 and plp1b are not expressed in MEP glia. These findings refine the molecular signature of MEP glia, enhancing their peripheral identity.