Chunk #42 — RESULTS — Transcription factors register the developmental history and contribute to the maintenance of PCP phenotypes — GABAergic neurons retain a transcription resume that registers their developmental history
As the 6 PCPs are embedded in 3 non-overlapping populations (PV, SST, VIP) derived from 2 separate developmental origins (MGE vs CGE) (Figure 7B), this data structure establishes a link between TF profiles in mature neurons to those in their embryonic precursors with cell type and single cell resolution. Almost all well-studied TFs in embryonic precursors maintain expression within the same clade of mature PCPs (Figure 7D, E): whereas Lhx6, Sox6, Mafb, Satb1 are expressed in PV and SST populations (the MGE clade), Coup-TF2, Sp8, Prox1, Npas1, Npas3; are expressed in VIP populations (the CGE clade). We further discovered additional TFs with similar patterns: whereas Tox family members (Tox, Tox2, Tox3) (Artegiani et al., 2015) are restricted to the MGE clade, Nfi family members (Nfia’, Nfib’, Nfix) (Piper et al.), Sall1 and Trp53i11 are restricted to the CGE clade. Importantly, by “reverse tracking” of their developmental history through screening the Allen Developmental Mouse Brain Atlas, we found that each of these TFs is indeed expressed in the embryonic MGE or CGE, consistent with their clade relationship (Figure 7I, Figure S7C).
