Abstract
During brain development neuroepithelial cells (NEs) divide symmetrically to maintain their pool, before their gradual transition into radial glial cells (RGCs). RGCs, that maintain some NEs features, begin to express glial markers, such as GFAP. RGCS generate in partially overlapping waves, neurons, astrocytes, oligodendrocytes and NG2-glia. Although RGCs are the main known neural progenitor cell (NPCs), recent studies have focused on the heterogeneity of neural progenitors. NG2 glia, is another remarkable cell type that can acts as a NPCs. In the adult brain mice, NG2-glia are capable of generating oligodendrocytes, astrocytes or even neurons. In addition, NG2-progenitor cells give rise to neurons, astrocytes, oligodendrocytes and NG2-glia. However, whether NG2-progenitors and GFAP-progenitors are the same or independent NPCs population remain unknown. In order to decipher the heterogeneity of NPCs we performed in utero electroporations in pregnant mice at different embryonic stages (E12, E14 and E16) with StarTrack constructs to tag NG2- or GFAP-progenitors and mouse embryonic brains were analyzed 48h later. After descriptive and quantitative analysis, we observed that the percentage of NG2-progenitors is higher at early embryonic stages and decrease during development. On the opposite, the portion of GFAP-progenitors increase with the development. In addition, very few NPCs co-expressed NG2 and GFAP. Thus, we found NG2-expressing progenitors, GFAP-expressing progenitors and NG2+GFAP-expressing progenitors, supporting the heterogeneity of NPCs.
