While neural induction begins before d1, the NGN2-iN heterogeneity emerges later as the expression of NGN2-iN subtype markers were detected after d1 (pseudotime Pt ∼0.4) (Figures S3B and S3I). Interestingly, we found that PHOX2B and POU4F1 had divergent expression from the beginning of their activation, while POU4F1 and GPM6A bifurcated later at d5 (pseudotime Pt ∼0.75) (Figures S3J and S3K). PRPH, on the other hand, was detected only after the PHOX2B and POU4F1 bifurcation, suggesting that it was activated independently in PHOX2B- and POU4F1-expressing cells (Figure S3I).
