Early lineage divergence segregates sensory and motor-associative identities in the thalamus.

Early lineage divergence in the embryonic mouse thalamus segregates sensory and motor-associative identities from distinct progenitor domains.

• Why it matters: Understanding how the thalamus develops its diverse functional nuclei is crucial for insights into brain circuit formation and function, yet the developmental principles remain unclear.
• What they did: The study generated a spatiotemporal single-cell multiomic and spatial transcriptomic atlas of the embryonic mouse thalamus, combined with lineage tracing, revealing two major glutamatergic lineages governed by different gene regulatory programs and arising from spatially distinct progenitors.
• The result: Findings show early segregation of sensory and motor-associative identities, with sensory lineages branching into visual and somatosensory neurons from a shared state, and identify Sp9 as a key regulator of visual thalamic fate, advancing understanding of thalamic modality specification.