Diversity of cortical progenitors directs neuronal layer formation and regional glial patterning

How distinct cortical progenitor types and their temporal differences influence neuronal and glial development remains a key question in neurobiology. While radial glial cells (RGCs) are well-established as neural progenitors (NPCs), NG2⁺NPCs have emerged as contributors with unique characteristics. Here, we combined in utero electroporation, lineage tracing and transcriptomic profiling to compare lineage outputs of NG2⁺ and GFAP⁺ NPCs in the developing mouse cortex. Both generate neurons and glia, but with partially distinct patterns in lineage output, spatial distribution, and fate bias. NG2⁺ NPCs undergo an early neurogenic phase followed by glial differentiation, producing glia with laminar distribution biases. In contrast, GFAP⁺ NPCs sustain neurogenesis longer, producing a broader range of neurons and more constant glia during development. Our findings highlight the contribution of progenitor identity and temporal differences to distinct, partially overlapping lineage trajectories, supporting a model in which fate potential and timing co-regulate the spatial and laminar organization of cortical cell types.